Статті в журналах: "In situ chemical analyses"

1

Ling, Zhigang, Naruhito Hori, Tadahisa Iwata, and Akio Takemura. "In-situ Analysis of Chemical Structure ofAPI Adhesive Using FT-NIR Spectroscopy." Journal of The Adhesion Society of Japan 51, s1 (2015): 322–31. http://dx.doi.org/10.11618/adhesion.51.322.

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2

Reddy, Ramana G., and V. Kumar. "Chemical In Situ Synthesis of Aluminum Alloy Composites." Materials Science Forum 561-565 (October 2007): 701–4. http://dx.doi.org/10.4028/www.scientific.net/msf.561-565.701.

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Aluminum alloys were reinforced with AlN particles using a novel chemical in situ technique. Thermodynamic analyses were made to identify the conditions for the in situ formation of the AlN in Al alloys. Experiments were conducted in the temperature range of 1173-1473 K by injecting ammonia gas. The composites with AlN quantity varying from 5 to 51 wt % were produced. Effect of process variables such as gas injection time, flow rate of ammonia gas and temperature of the alloy melt on the formation of AlN was studied. Increase in either injection time or flow rate of the ammonia gas increased the nitride content. AlN particles with an average size of 500 nm were produced. The measured Vickers hardness of the composites formed increased with increasing AlN content. The amount of AlN experimentally formed is in good agreement with the thermodynamically predicted data.

3

Bierman, Paul R., and Alan R. Gillespie. "Evidence Suggesting That Methods of Rock-Varnish Cation-Ratio Dating Are neither Comparable nor Consistently Reliable." Quaternary Research 41, no. 1 (January 1994): 82–90. http://dx.doi.org/10.1006/qres.1994.1009.

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AbstractUsing samples from a prehistoric quarry site in the Mojave Desert, we tested and compared the two principal methods of rock-varnish cation-ratio dating, analysis of rock-varnish scrapings (R. I. Dorn, 1983, Quaternary Research 20, 49-73 and 1989, Physical Geography 13, 559-596) and analysis of rock varnish in situ (C. D. Harrington and J. W. Whitney, 1987, Geology 15, 967-970). Because we found no consistent relationship between the varnish cation ratio (K + Ca)/Ti, and the relative age of the varnish, neither method could be used to "cation-ratio date" the underlying chert artifacts. Moreover, in situ analyses yielded systematically higher cation ratios and lower Ti abundances than bulk analyses of scraped varnish or microprobe analyses of varnish in cross section. Our results, when considered along with other recently published evidence, indicate that these two methods of varnish chemical analysis and cation-ratio dating may not be comparable, nor consistently reliable, chronometers.

4

Buccolieri, Giovanni, Antonio Serra, Giorgio Giuseppe Carbone, Vito Nicola Iacobellis, Alfredo Castellano, Lucio Calcagnile, and Alessandro Buccolieri. "In Situ Investigation of the Medieval Copper Alloy Door in Troia (Southern Italy)." Heritage 6, no. 3 (March 2, 2023): 2688–700. http://dx.doi.org/10.3390/heritage6030142.

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This work describes experimental results concerning the chemical composition of the alloy patina and inlays from the medieval copper alloy door of the cathedral of Troia (southern Italy), dating back to 1127 CE. The analyses were conducted in situ with no sampling or sample preparation required, using a portable energy-dispersive X-ray fluorescence (ED-XRF) instrument. The compositional results show that the two door leaves were made using a binary alloy of copper and lead, while the nails, lion protomes, and handles have a different chemical composition. Moreover, the analyses revealed uniform concentrations of chlorine, probably due to cleaning treatments during the restoration. It is important to emphasise that the obtained results are the only ones related to this valuable masterpiece analysed.

5

Ten Cate, J. M. "In Situ Models, Physico-Chemical Aspects." Advances in Dental Research 8, no. 2 (July 1994): 125–33. http://dx.doi.org/10.1177/08959374940080020201.

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In situ (intra-oral) caries models are used for two purposes. First, they provide information about oral physiological processes. Such information helps to detail our knowledge of the oral ecosystem and to verify conclusions from in vitro experiments. Second, in situ models are utilized to test preventive agents in the phase between laboratory testing and clinical trials. Most investigations involving enamel inserts have been aimed at testing new dentifrices. The experimental designs of such studies usually do not allow one to draw conclusions on physico-chemical processes, e.g., because of single point measurements. Studies of model parameters (lesion type, lesion severity, and de/remineralization in time) constitute only a minority of the research reports. The most striking observation obtained with in situ models has been the significant differences in de/remineralization observed among individuals and, more importantly, within one individual during different time periods and between different sites in the same mouth (for review, see ten Cate et al., 1992). Regardless of this, some general findings can be inferred: During in situ demineralization, up to 62 vol%μm/day may be removed from enamel. For dentin specimens, this value may be as high as 89 vol%μm/day. For remineralization, during fluoride dentifrice treatment, a median deposition rate of 0.7%/day (for lesions with integrated mineral loss values between 2000 and 4000 vol%μm) is found. The rate of deposition seems to be correlated with the extent of the pre-formedlesion. This suggests that the number of sites (crystallite surface) available for calcium phosphate precipitation is an important parameter. However, the rate at which mineral ions are supplied (by saliva) could also be a limiting factor, as is shown in a theoretical analysis of mass-balance of enamel constituents. The few studies that have monitored caries development in time reveal that mineral loss (and also lesion progression in depth) from enamel in situ is linear in time. This is in contrast to results from laboratory findings.

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Farr, Nicholas T. H. "Revealing Localised Mechanochemistry of Biomaterials Using In Situ Multiscale Chemical Analysis." Materials 15, no. 10 (May 11, 2022): 3462. http://dx.doi.org/10.3390/ma15103462.

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The study of mechanical and chemical phenomena arising within a material that is being subjected to external stress is termed mechanochemistry (MC). Recent advances in MC have revealed the prospect not only to enable a greener route to chemical transformations but also to offer previously unobtainable opportunities in the production and screening of biomaterials. To date, the field of MC has been constrained by the inability of current characterisation techniques to provide essential localised multiscale chemically mapping information. A potential method to overcome this is secondary electron hyperspectral imaging (SEHI). SEHI is a multiscale material characterisation technique applied within a scanning electron microscope (SEM). Based on the collection of secondary electron (SE) emission spectra at low primary beam energies, SEHI is applicable to the chemical assessment of uncoated polymer surfaces. Here, we demonstrate that SEHI can provide in situ MC information using poly(glycerol sebacate)-methacrylate (PGS-M) as an example biomaterial of interest. This study brings the use of a bespoke in situ SEM holder together with the application of SEHI to provide, for the first time, enhanced biomaterial mechanochemical characterisation.

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Kliewer, C. E., M. M. Disko, S. L. Soled, and G. J. DeMartin. "A Reactor for “Ex-Situ” TEM Catalyst Characterization." Microscopy and Microanalysis 5, S2 (August 1999): 926–27. http://dx.doi.org/10.1017/s1431927600017955.

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The microstructural and chemical characterization of catalysts is not only integral to their initial development but also to understanding and controlling their behavior over time. To better elucidate the morphology of these materials and relate physical properties to catalytic properties (e.g., activity, selectivity, etc.), “ex-situ” methods for studying catalysts under reactive conditions have been developed.Because conventional transmission electron microscopy (CTEM) is conducted under high vacuum conditions, it is difficult to replicate the exact chemical environment of a catalyst (e.g., high pressure, variable gas mixtures, etc) within the TEM. Consequently, most analyses focus on comparing “fresh” and “spent” materials. In general, this methodology provides useful structural information albeit with limitations associated with the comparison of dissimilar regions and the effects of sampling inhomogenieties.

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Pratapa, Y. Reddy, K. L. Narayana, and M. Kedar Mallik. "Ex Situ Tribological and Electro-chemical analysis of Aluminium." Journal of Physics: Conference Series 2070, no. 1 (November 1, 2021): 012205. http://dx.doi.org/10.1088/1742-6596/2070/1/012205.

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Abstract Aluminium sample coupon is evaluated for electro-chemical, tribological and microstructural study under selected test conditions. Aluminium is a light-weight material chiefly preferred in fields like automobile, aerospace, marine and satellite domestic appliances etc. Moreover, due to its specific characteristics, it plays a crucial role in industries and research fields. In the present work, the ex situ tribological (wear test), electrochemical (corrosion test), mechanical (microhardness test) and microstructural (nodularity percentage) behaviours of Aluminum sample is presaged. The test results reveal that, when experiment advance, with respect to time the wear rate increases, frictional force is decreased and pin temperature increased. The corrosion test is held on specimen coupon in two modes, before and after wear test, and observed that the corrosion rate gets improved on specimen after wear test. Nodularity analysis also express that the nodularity percentage is increased by 5%. Before wear test, the percentage of accepted count to total count of nodules on texture is 65.18%, while the percentage after wear test is found to be 70.29%. The Vickers Microhardness analysis exhibits the hardness value as 160 HV on Vickers Hardness Scale.

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Parnell, J. Jacob, Richard E. Terry, and Payson Sheets. "Soil Chemical Analysis of Ancient Activities in Cerén, El Salvador: A Case Study of a Rapidly Abandoned Site." Latin American Antiquity 13, no. 3 (September 2002): 331–42. http://dx.doi.org/10.2307/972114.

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Activities performed over long periods of time tend to leave soil chemical residues as evidence of those activities. Some of the questions studied in this paper deal with the interpretive capabilities provided by chemical patterns. Soil samples from Cerén, El Salvador, a well-preserved site, were analyzed for extractable phosphorus and heavy metals. We compared in situ artifacts collected from the site with chemical signatures that indicate activity areas. We found that elevated concentrations of phosphorus were associated with food preparation, consumption, and disposal. Heavy metals were associated with the interior of the structure where pigments and painted gourds were found. In this case, where well-preserved, in situ artifacts were available for analysis, we found that chemical analysis was effective in locating human activity areas. Our findings indicate that chemical analysis can be used to guide interpretation in areas of poor artifact preservation with reasonable accuracy, and in archaeological sites that underwent gradual abandonment.

10

Herzog, Benjamin M., Simon M. Kleinknecht, Claus P. Haslauer, and Norbert Klaas. "Experimental upscaling analyses for a surfactant-enhanced in-situ chemical oxidation (S-ISCO) remediation design." Journal of Contaminant Hydrology 258 (September 2023): 104230. http://dx.doi.org/10.1016/j.jconhyd.2023.104230.

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Milanesio, Marco, Luca Palin, Davide Viterbo, Rocco Caliandro, Atsushi Urakawa, Wouter van Beek, and Dmitry Chernyshov. "Chemical Selectivity in Diffraction by Statistical Analysis of in situ XRPD Data." Acta Crystallographica Section A Foundations and Advances 70, a1 (August 5, 2014): C1471. http://dx.doi.org/10.1107/s2053273314085283.

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X-ray diffraction methods in general allow only a limited chemical selectivity. Structural information on a subset of atoms can be obtained by a modulation enhanced diffraction (MED) experiment, using a periodic stimulus supplied in situ on a crystal, while diffraction data are collected several times within a stimulus period. The data are then treated by statistical methods such as phase sensitive detection (PSD) and Principal component analysis (PCA) techniques. The application of PSD to diffraction has been proposed as a tool to extract crystallographic information on a subset of atoms [1], thus allowing to introduce selectivity in diffraction. Simulated and experimental PSD-MED powder data were produced by using a TS-1 zeolite as spectator, in which Xe, acting as active species, is adsorbed and desorbed in a periodically modulated mode. By first demodulating these data, MED allowed to obtain the powder diffraction pattern of the active subset, i.e. to obtain selectively the crystallographic information on Xe, by solving the crystal structure of the active species out of the zeolite framework. The "real world" experiments indicated that the PSD-MED approach has some limitations related to its theoretical assumptions. PCA is widely used in spectroscopic analyses and was recently applied to XRPD data by some of us [2]. PCA was exploited to evaluate the in situ XRPD data quality, to speed up the data analysis and data pre-treatment required by PSD and improve the extraction of the substructure information from MED data. It resulted that the first two components obtained by PCA are related to the 1- and 2-omega patterns from PSD. The two approaches (PCA and PSD) are finally compared from the viewpoint of their capacity of gathering information on the Xe substructure inside the zeolite channels and used in a synergic way to obtain the optimal data analysis efficiency.

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Schnitzer, Morris. "The in situ analysis of organic matter in soils." Canadian Journal of Soil Science 81, no. 3 (August 1, 2001): 249–54. http://dx.doi.org/10.4141/s00-064.

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Traditionally, studies on soil organic matter (SOM) begin with the extraction of SOM from soils, its fractionation into humic acid, fulvic acid, and humin, followed by de-ashing of each fraction. These are tedious, laborious and inefficient procedures that do not provide any chemical information on these materials. Instead, recently developed methods such as solid-state 13C NMR and pyrolysis – field ionization mass spectrometry (Py-FIMS) can now be used for the in situ analysis of SOM in soils. These methods identify the major chemical components of SOM without extractions and fractionations, and yield valuable information on the main chemical structures in these materials. A better knowledge of the structural chemistry of SOM will help SOM chemists and other soil scientists to better understand the complex chemical and biochemical reactions that occur in soils, and will enable them to develop practices that will improve soil management and soil productivity. Key words: Extraction, fractionation, solid state 13C NMR, pyrolysis-field ionization mass spectrometry, chemical composition

13

Gai, Pratibha L., and Edward D. Boyes. "In situ visualisation and analysis of dynamic single atom processes in heterogeneous catalysts." Journal of Materials Chemistry A 10, no. 11 (2022): 5850–62. http://dx.doi.org/10.1039/d1ta08307d.

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Vykhodets, V. B., and T. E. Kurennykh. "In-situ nuclear reaction analysis." Diagnostics, Resource and Mechanics of materials and structures, no. 4 (June 2021): 6–14. http://dx.doi.org/10.17804/2410-9908.2021.4.006-014.

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The principles of in-situ nuclear reaction techniques and the need for them in various fields of scientific research are considered; several examples of the application of these techniques are given. It is shown that the techniques of in-situ nuclear reactions are effective in studying the diffusion of deuterium in metals at temperatures below room temperature, the diffusion of deuterium in proton-conducting oxides, the quantum diffusion of deuterium in metals at cryogenic temperatures, and the chemical composition of oxide nanopowders when they are heated in vacuum. Promising applications of nuclear reaction techniques in situ are formulated.

15

Mahdavi, Ali, Ali Nikkhah, and Fatemeh Alemi. "The comparison between nylon bag and gas production method, use of regression equations in determination of feedstuffs nutritive value." Proceedings of the British Society of Animal Science 2007 (April 2007): 211. http://dx.doi.org/10.1017/s1752756200021141.

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The in situ technique forms the basis of many feed evaluation systems for ruminants. Although this method is widely used, the NBT is very laborious, time-consuming, and incubations and analyses of the feed residues often last several weeks. Therefore, several other techniques have been investigated to measure and predict ruminal degradation of various chemical components of feedstuffs. The aim of this study is to investigate the possibilities of estimating in situ degradation characteristics of DM, CP, ADF and NDF in several feedstuffs by gas production characteristics and chemical composition.

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Oueslati, Walid. "Effect of Soil Solution pH during the Tetracycline Intercalation on the Structural Properties of a Dioctahedral Smectite: Microstructural Analysis." Journal of Nanomaterials 2019 (September 12, 2019): 1–17. http://dx.doi.org/10.1155/2019/7414039.

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The aim of this work is to quantitatively characterize the structural response to a chemical disruption of saturated montmorillonite crystallites by organic molecules (tetracycline (TC)), derived from pharmaceutical waste. The chemical disturbance is performed by varying the surrounding soil solution pH. To show the effect of this chemical perturbation on the interlamellar space (IS) configuration and the hydration properties, an “in situ” XRD analysis, based on the modeling of the 00l reflections, is carried out. The “in situ” XRD analysis is performed by varying the relative humidity conditions (%RH). FTIR SEM and BET- (Brunauer-Emmett-Teller-) BJH (Barrett-Joyner-Halenda) analyses are used as complementary techniques to confirm the structural changes accompanying the intercalation process. Results showed a dependence between solution acid character and the TC adsorption mechanism. From pH values close to 7, the deprotonation of the TC molecule within IS is accelerated by an increasing %RH rate. IR spectroscopy shows that the structure is preserved versus pH value and only a shift of the water deformation bands ascribed to interlamellar water molecule abundance and TC conformation is observed. The surface morphology studied by SEM shows the increase in the surface porosity by increasing the pH value. BET-specific surface area and BJH pore size distribution (PSD) analyses confirm the SEM observations.

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Huang, Saisai, Qiufang Jiang, Bin Yu, Yujing Nie, Zhongqing Ma, and Lingfei Ma. "Combined Chemical Modification of Bamboo Material Prepared Using Vinyl Acetate and Methyl Methacrylate: Dimensional Stability, Chemical Structure, and Dynamic Mechanical Properties." Polymers 11, no. 10 (October 11, 2019): 1651. http://dx.doi.org/10.3390/polym11101651.

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Acetylation and in situ polymerization are two typical chemical modifications that are used to improve the dimensional stability of bamboo. In this work, the combination of chemical modification of vinyl acetate (VA) acetylation and methyl methacrylate (MMA) in situ polymerization of bamboo was employed. Performances of the treated bamboo were evaluated in terms of dimensional stability, wettability, thermal stability, chemical structure, and dynamic mechanical properties. Results show that the performances (dimensional stability, thermal stability, and wettability) of bamboo that was prepared via the combined pretreatment of VA and MMA (VA/MMA-B) were better than those of raw bamboo, VA single-treated bamboo (VA-B), and MMA single-treated bamboo (MMA-B). According to scanning electron microscopy (SEM) and Fourier transform infrared spectroscopy (FTIR) analyses, VA and MMA were mainly grafted onto the surface of the cell wall or in the bamboo cell lumen. The antiswelling efficiency and contact angle of VA/MMA-B increased to maximum values of 40.71% and 107.1°, respectively. From thermogravimetric analysis (TG/DTG curves), the highest onset decomposition temperature (277 °C) was observed in VA/MMA-B. From DMA analysis, the storage modulus (E’) of VA/MMA-B increased sharply from 15,057 Pa (untreated bamboo) to 17,909 Pa (single-treated bamboo), and the glass transition temperature was improved from 180 °C (raw bamboo) to 205 °C (single-treated bamboo).

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Graikou, Konstantia, Anna Mpishinioti, Nikolaos Tsafantakis, Eleni Maloupa, Katerina Grigoriadou, and Ioanna Chinou. "Comparative Phytochemical Analyses of Flowers from Primula veris subsp. veris Growing Wild and from Ex Situ Cultivation in Greece." Foods 12, no. 13 (July 6, 2023): 2623. http://dx.doi.org/10.3390/foods12132623.

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In the last decades, Primula veris subsp. veris (roots and flowers) has been over harvested through legal and illegal ways in Greece, due to its extremely high commercial demand, as it is used in industry because of its well-known therapeutic properties. As ex situ cultures of the plant have been already developed, in the current comparative study, the herbal teas (infusions) from both flowers of cowslip growing wild in the Prespa Lake Park (NW Greece), and from ex situ propagated and cultivated plant material, have been investigated, with the ultimate goal of assessing them qualitatively. Furthermore, through classic phytochemical studies, the ten most abundant metabolites, belonging to the chemical categories of flavonol-glycosides and methoxy flavones, have been identified and structurally determined. The chemical profile of both infusions has been further analyzed through UHPLC-HRMS, showing that they show only light differences. The total phenolic content (TPC) of both studied samples (wild and ex situ cultivation), was determined by the Folin–Ciocalteau method, followed by an antioxidant activity assay though DPPH where, in both cases, wild plants exerted higher phenolic load and stronger antioxidative properties. According to the reported results, it could be proposed that the ex situ cultivated plant material could facilitate the mass production of plants and the sustainable cultivation of cowslip in the Greek mountains.

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Pecha, M. Brennan, Kristiina Iisa, Michael Griffin, Calvin Mukarakate, Richard French, Bruce Adkins, Vivek S. Bharadwaj, et al. "Ex situ upgrading of pyrolysis vapors over PtTiO2: extraction of apparent kinetics via hierarchical transport modeling." Reaction Chemistry & Engineering 6, no. 1 (2021): 125–37. http://dx.doi.org/10.1039/d0re00339e.

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Clarke, A. N., R. D. Mutch, D. J. Wilson, and K. H. Oma. "Design and Implementation of Pilot Scale Surfactant Washing/Flushing Technologies including Surfactant Reuse." Water Science and Technology 26, no. 1-2 (July 1, 1992): 127–35. http://dx.doi.org/10.2166/wst.1992.0393.

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Chemicals with low solubility, volatility, and biodegradability can be very hard to treat in soils. These chemicals may however by addressed by surfactant supplemented technologies. PCBs are a prime example of difficult chemicals and were used frequently in the studies. The surfactant enhances the solubility of the chemicals, therefore effecting their desorption and more efficient treatment. ECKENFELDER INC. has completed laboratory scale experiments simulating in situ/ex situ surfactant treatment of various types of chemicals, singly and in combination, and has built a pilot scale unit for the surfactant treatment of contaminated soils. The pilot scale system includes surfactant recycle and reuse of an anionic surfactant, sodium dodecyl sulfate, SDS. The resultant volume of contaminants is reduced many fold, thus consistent with US regulatory requirements as well as reducing final disposal costs. In addition to the pilot scale unit, studies were made on the impact of non equilibrium (e.g., desorption, diffusion, etc.) effects on treatment efficiency as well as developing “real time” chemical analyses of PCBs in SDS solution. A mathematical model has also been developed which assists with design/performance assessments.

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Anderson, Timothy I., and Anthony R. Kovscek. "Analysis and comparison of in-situ combustion chemical reaction models." Fuel 311 (March 2022): 122599. http://dx.doi.org/10.1016/j.fuel.2021.122599.

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Qian, Yuqin, Gang-hua Deng, and Yi Rao. "In Situ Chemical Analysis of the Gas–Aerosol Particle Interface." Analytical Chemistry 90, no. 18 (August 15, 2018): 10967–73. http://dx.doi.org/10.1021/acs.analchem.8b02537.

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Bas, Corine, Marie Crouillere, Florence Dubelley, Mylène Robert, Assma El Kaddouri, Olivier Lottin, Jérôme Dillet, Kévin Mozet, and Jean Christophe Perrin. "Embrittlement of PFSA Reinforced Membrane Interfaces after Ex-Situ Chemical-Mechanical Aging." ECS Meeting Abstracts MA2023-02, no. 39 (December 22, 2023): 1881. http://dx.doi.org/10.1149/ma2023-02391881mtgabs.

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Perfluorosulfonic acid (PFSA) membrane degradation has been identified as one of the main factors responsible for the short lifetime of PEMFCs [1,2]. The aging mechanisms of these membranes are complex due to mechanical fatigue combined to chemical aggressions. Mechanical fatigue results from the wetting/drying cycles while the chemical aggressions are induced by radicals formed during fuel cell operation. Although it is commonly accepted that chemical and mechanical stresses can interact to accelerate membrane degradation [3], coupled studies are rarely conducted. Thus, an original experimental set-up to perform ex-situ aging tests combining membrane exposure to cyclic mechanical stresses to a free radical environment under conditions close to those observed during cell operation has been developed [4]. Ex-situ aging was performed on PFSA membranes reinforced (Nafion™ XL) with a cyclic compression oscillating between 0 - 10 MPa (0.1 Hz frequency) and a Fenton solution containing 1 ppm Fe2+ and 3 %vol H2O2. Such stresses revealed a significant morphological alteration with the appearance of “bubbles” close to the surface membrane (Figure 1, left). No chemical structure modification was detected within the three different layers. Nevertheless, SEM-EDX, FTIR and Raman microscopic analyses highlight delamination close to the reinforcement/PFSA interface (Figure 1, rigth). Additional peeling tests argued this failure point in the Nafion™ XL membrane. Figure 1

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Ajith Kumar, Kumaraswamy Kaliamma, Krishnaswamy Raghukandan, Uma Thanu Subramonia Pillai, Bellambettu Chandrasekhara Pai, and Madhusudan Chakraborty. "Processing and Microstructure of Magnesium In Situ Composite with Titanium and Boron Based Reinforcement." Materials Science Forum 710 (January 2012): 389–94. http://dx.doi.org/10.4028/www.scientific.net/msf.710.389.

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The present work is aimed to investigate the in-situ TiB/TiB2 particle formation in Mg and Mg-Al alloy via the chemical reaction between Mg, Al, K2TiF6 and KBF4. The feasibility to produce the Mg and Mg-Al matrix with in-situ TiB2 and TiB particles have been studied with respect to processing parameters. The XRD, optical microscopy and SEM-EDX analyses have been carried out on the synthesised composites. Significant improvement in the hardness values are obtained for the in-situ composite compared to the base alloys.

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Vojinovic, Vojislav, J. M. S. Cabral, and L. R. Fonseca. "Ex situ bioprocess monitoring techniques." Chemical Industry and Chemical Engineering Quarterly 13, no. 2 (2007): 103–16. http://dx.doi.org/10.2298/ciceq0702103v.

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Rapid development of biotechnology resulted in increasing need for bioprocess monitoring and control. Efficient process control allows optimization of process efficiency and productivity, reduction of costs and pollution, and quality control. In situ sensors for real-time bioprocess monitoring have been recently reviewed. In this paper the use of ex situ techniques for real time (or quasi real time) monitoring methods is reviewed. These include mass spectrometry, gas chromatography, methods based on semiconductor gas sensors and electronic noses for the analysis of dissolved gas and bioreactor head-space, and on-line liquid chromatography and capillary electrophoresis, spectroscopy and biosensors for monitoring of the bulk process media. Flow techniques allow for the analysis to be carried out ex situ, out of the reactor reintroducing various detection methods that are impossible to implement in an in situ set-up. Because of their versatility flow analysis techniques (continuous and segmented flow analysis, flow injection analysis, sequential injection analysis and bead injection analysis) are broadly used for sample handling and analysis of the bulk media, and their applications in bioprocess monitoring are discussed.

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Anvarov, Adyl, Adelaida Pelaez Angel, Beatriz Felices Rando, and Jimena Lazaro Gil. "Remediation of groundwater contamination from an old, non-functional landfill in Hořkovec open cast mine, Czech Republic." Journal of Water Supply: Research and Technology-Aqua 68, no. 8 (November 28, 2019): 829–41. http://dx.doi.org/10.2166/aqua.2019.198.

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Abstract The main aim of this work was to assess different suitable strategies for the remediation of groundwater contaminated with the leachate from an old, not functional landfill located next to Hořkovec open cast mine, in the Czech Republic. The leachate consisted of mainly chlorinated aliphatic compounds and aromatic volatile compounds. The site, that had already been treated, was observed to show rebounding effects after the first remediation treatment. This article analyses the possibilities of using different types of remediation technologies that include in-situ chemical oxidation (ISCO) with different oxidants (potassium permanganate, sodium permanganate and sodium persulfate), as well as in-situ bioremediation (ISB), and the combination of both types of treatment. From the results of the analysis it was concluded that the best option for this case was to carry out a pre-treatment of the area by ISCO with sodium persulfate as the oxidant agent and then a further biological treatment.

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Ng, T. C. A., and H. Y. Ng. "Physico-chemical characterisation versus in situ micro-structural characterisation of membrane fouling in membrane bioreactors." Water Science and Technology 63, no. 8 (April 1, 2011): 1781–87. http://dx.doi.org/10.2166/wst.2011.196.

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Fouling characteristics of aerobic submerged membrane bioreactors were analysed under two different membrane materials. Polyethersulfone (PES) membranes were found to foul faster at sub-critical flux than polyolefin (PO) membranes. Physico-chemical characterisation, by means of comparison of extracellular polymeric substances (EPS) and soluble microbial products (SMP) concentrations, as well as the mixed liquor suspended solids (MLSS) concentration were unable to explain the differences in membrane fouling of the contrasting membrane materials. The use of confocal laser scanning microscopy (CLSM) to image organic foulants directly on the membrane surface, coupled with image analyses showed that membrane fouling mechanism shifted from a biofilm initiated process on PO membranes to a bio-organic dominated process on PES membranes under sub-critical flux conditions. These results show that physico-chemical characterisation of an MBR process may not effectively distinguish the effectiveness of different membrane materials, so long as operating conditions are identical, and that characterisation of foulants on the membrane surfaces was necessary to elucidate the differences in membrane fouling.

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Akhlaghi, Maryam, Esmaeil Salahi, Seyed Ali Tayebifard, and Gert Schmidt. "Role of Ti3AlC2 MAX phase on characteristics of in-situ synthesized TiAl intermetallics. Part III: microstructure." Synthesis and Sintering 2, no. 1 (March 20, 2022): 20–25. http://dx.doi.org/10.53063/synsint.2022.2182.

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In this paper, the 3rd part of a series of publications on the sinterability and characteristics of TiAl–Ti3AlC2 composites, the microstructure development during the synthesis and sintering processes was studied by scanning electron microscopy (SEM). Chemical evaluation of various phases in the developed microstructures was performed using energy-dispersive X-ray spectroscopy (EDS) in different ways such as point, line scan and two-dimensional elemental map analyses. For this purpose, five samples were fabricated with different percentages of Ti3AlC2 MAX phase additive (10, 15, 20, 25 and 30 wt%). Ball-milling and spark plasma sintering (SPS: 900 °C/7 min/40 MPa) of as-purchased Al and Ti powders with already-synthesized Ti3AlC2 additive were selected as composite making methodology. SEM/EDS analyses verified the in-situ manufacturing of TiAl/Ti3Al intermetallics as the matrix during the SPS process and the presence of Ti3AlC2 as the ex-situ added secondary phase. Moreover, the in-situ synthesis of Ti2AlC, another member of MAX phases in Ti-Al-C system, was also detected in titanium aluminide grain boundaries and attributed to a chemical reaction between TiC (an impurity in the initial Ti3AlC2 additive) and TiAl components.

29

Tóth, Márton, Csaba Ilyés, and Péter Szűcs. "Chemical composition analysis of thermal water of Hajdúdorog." Multidiszciplináris tudományok 12, no. 3 (2022): 299–306. http://dx.doi.org/10.35925/j.multi.2022.3.28.

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In our work, a chemical analysis of the thermal water of Hajdúdorog was performed to identify the therapeutic possibilities of the water. Two sampling campaigns were performed in August 2021 and March 2022. The chemical composition and characteristic of thermal water were determined in situ on-site and in labor investigations. According to the chemical analysis, we found the water type of thermal water is very rare, called NaCl type like the seawater. Its rareness is known by Lajos Marton (Marton, 2009; Marton, 2013), only 3,5% of the thermal waters of the Hungarian Great Plain can be grouped into the sodium chloride water type. But the high bromine (0.9 mg/l) and its supposed iodine content of the thermal water can make it unique in therapeutic application. Some trace metals (Cu, Fe, Mn) also increase the healing effect of water.

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Francaviglia, Nadia, Angela Lombardo, and Stefania Caramanna. "Conservation Work on an Ancient Sicilian Processional Banner: Preliminary Analyses and in Situ Restoration." Procedia Chemistry 8 (2013): 109–16. http://dx.doi.org/10.1016/j.proche.2013.03.015.

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31

Cordoba, Aldo, Juan Valerio Cauich-Rodríguez, Rossana Faride Vargas-Coronado, Rodrigo Velázquez-Castillo, and Karen Esquivel. "A Novel In Situ Sol-Gel Synthesis Method for PDMS Composites Reinforced with Silica Nanoparticles." Polymers 16, no. 8 (April 17, 2024): 1125. http://dx.doi.org/10.3390/polym16081125.

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The addition of nanostructures to polymeric materials allows for a direct interaction between polymeric chains and nanometric structures, resulting in a synergistic process through the physical (electrostatic forces) and chemical properties (bond formation) of constituents for the modification of their properties and potential cutting-edge materials. This study explores a novel in situ synthesis method for PDMS-%SiO2 nanoparticle composites with varying crosslinking degrees (PDMS:TEOS of 15:1, 10:1, and 5:1); particle concentrations (5%, 10%, and 15%); and sol-gel catalysts (acidic and alkaline). This investigation delves into the distinct physical and chemical properties of silicon nanoparticles synthesized under acidic (SiO2-a) and alkaline (SiO2-b) conditions. A characterization through Raman, FT-IR, and XPS analyses confirms particle size and agglomeration differences between both the SiO2-a and SiO2-b particles. Similar chemical environments, with TEOS and ethanol by-products, were detected for both systems. The results on polymer composites elucidate the successful incorporation of SiO2 nanoparticles into the PDMS matrix without altering the PDMS’s chemical structure. However, the presence of nanoparticles did affect the relative intensities of specific vibrational modes over composites from −35% to 24% (Raman) and from −14% to 59% (FT-IR). The XPS results validate the presence of Si, O, and C in all composites, with significant variations in atomic proportions (C/Si and O/Si) and Si and C component analyses through deconvolution techniques. This study demonstrates the successful in situ synthesis of PDMS-SiO2 composites with tunable properties by controlling the sol-gel and crosslinking synthesis parameters. The findings provide valuable insights into the in situ synthesis methods of polymeric composite materials and their potential integration with polymer nanocomposite processing techniques.

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de Almeida Duarte, Luis Felipe, Caroline Araújo de Souza, Camilo Dias Seabra Pereira, and Marcelo Antonio Amaro Pinheiro. "Metal toxicity assessment by sentinel species of mangroves: In situ case study integrating chemical and biomarkers analyses." Ecotoxicology and Environmental Safety 145 (November 2017): 367–76. http://dx.doi.org/10.1016/j.ecoenv.2017.07.051.

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Matusiewicz, Henryk, and Magdalena Krawczyk. "Determination of nickel by chemical vapor generation in situ trapping flame AAS." Open Chemistry 9, no. 4 (August 1, 2011): 648–59. http://dx.doi.org/10.2478/s11532-011-0044-4.

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AbstractThe analytical performances of coupled chemical vapor generation, integrated atom trap (CVG-IAT) atomizer flame atomic absorption spectrometry (FAAS) system were evaluated for determination of nickel in environmental samples. Nickel chemical vapors are atomized in an air-acetylene flame-heated IAT. A new design of CVG-IAT-FAAS hyphenated technique that would exceed the operational capabilities of existing arrangements (a water-cooled single silica tube, double-slotted quartz tube) permitting construction of an “integrated trap” was investigated. An improvement in limit of detection was achieved compared with that obtained using any of the above atom trapping techniques separately. The concentration limit of detection was 1 ng mL−1 for Ni. The overall efficiencies of the vapor generation process was estimated to be ca. 50%. For a 2 min in situ pre-concentration time, sensitivity enhancement, compared to FAAS, was 200 folds for Ni, using vapor generation atom trapping technique. The sensitivity can be further improved by increasing the collection time. The precision of the measurements for 25 ng mL−1 of Ni was 9% RSD. The accuracy of this method was tested by analyses of NIST SRM 2704 (Buffalo River Sediment), NIST SRM 1648 (Urban Particulate Matter), NIST SRM 2710 (Montana Soil), NBS SRM 1633a (Coal Fly Ash) and NIST SRM 1643e (Trace Element in Water) certified reference materials. The measured Ni content in five reference materials was in satisfactory agreement with the certified values (in the range of 14.3–98 μg g−1). The hyphenated technique was applied for nickel determination in coal fly ash, soil, sediment, sewage and river water.

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Kośmider, Beata, Regina Osiecka, and Jan T. Siciński. "Application of micronucleus assay in plants to monitor environmental pollution in situ." Acta Universitatis Lodziensis. Folia Biologica et Oecologica 4 (January 1, 2008): 37–49. http://dx.doi.org/10.18778/1730-2366.04.03.

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Samples of 5 vascular plant species: Achillea millefolium L., Artemisia vulgaris L., Festuca gigantea (L.) VILL., Ranunculus acris L. s. str. and Vicia angustifolia L. were collected near Fuel Storage Station, Chemical Fibre Factory “Wistom” in Tomaszów Mazowiecki and Sewage Treatment Plant in Sulejów. Genotoxicity of environmental pollution was analysed using micronucleus assays in pollen mother and root tip cells in comparison with plant material collected in the Tatra and Babia G óra National Parks. Abnorm alities in morphology of plants growing in polluted areas were also found. The cytogenetical analyses revealed positive correlation between the percentage of micronuclei and the presence of heavy metals in soil. Pollen mother cells (germ line) were found more susceptible to DNA damage as compared with root tip cells (somatic line).

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Makunza, John K., and G. Senthil Kumaran. "Analyses of Deteriorating Old Masonry Buildings; Characterisation of Materials for Establishment of their Compatible Repairs." International Journal of Engineering Research in Africa 15 (April 2015): 47–61. http://dx.doi.org/10.4028/www.scientific.net/jera.15.47.

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Most of the Governmental and religious building structures in Rungwe district are masonry structures built during the German East Africa period. These structures are deteriorating despite of various efforts on their repair intervention using modern cements and paints. This paper studies the types of mineral binders used, composition and physical characteristics of these in-situ mortar materials for the purpose of deciding on their appropriate compatible repair materials. Field observations and investigations, laboratory materials testing and review of the literature showed that the in-situ mortar materials constituted of sub-hydraulic lime mineral binders to natural sand (1:3) mortars. Currently there are no producers of hydraulic lime in Africa and a limited production worldwide. Mix design and analysis of locally available hydrated lime plus pozzolana natural sand (1:3) mortar material have shown compatibility in chemical and major physical properties and characteristics with the substrate in-situ hardened sub-hydraulic masonry mortars. Therefore use of these repair mortars is recommended for compatible repairs to these masonry structures and as a regional alternative to cement based materials for low rise masonry structures.

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Li, Hongkai, Tongqing Wang, Qian Zhao, Yonggang Meng, and Xinchun Lu. "Kinematic analysis of in situ measurement during chemical mechanical planarization process." Review of Scientific Instruments 86, no. 10 (October 2015): 105118. http://dx.doi.org/10.1063/1.4934366.

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37

Short, R. T., D. P. Fries, M. L. Kerr, C. E. Lembke, S. K. Toler, P. G. Wenner, and R. H. Byrne. "Underwater mass spectrometers for in situ chemical analysis of the hydrosphere." Journal of the American Society for Mass Spectrometry 12, no. 6 (June 2001): 676–82. http://dx.doi.org/10.1016/s1044-0305(01)00246-x.

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38

Hawthorne, Steven B., David J. Miller, David E. Nivens, and David C. White. "Supercritical fluid extraction of polar analytes using in situ chemical derivatization." Analytical Chemistry 64, no. 4 (February 15, 1992): 405–12. http://dx.doi.org/10.1021/ac00028a015.

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39

Könemann, Sarah, Yvonne Müller, Daniel Tschentscher, Martin Krauss, Pedro Inostroza, Ira Brückner, Johannes Pinnekamp, Sabrina Schiwy, and Henner Hollert. "Combination of In Situ Feeding Rate Experiments and Chemical Body Burden Analysis to Assess the Influence of Micropollutants in Wastewater on Gammarus pulex." International Journal of Environmental Research and Public Health 16, no. 5 (March 11, 2019): 883. http://dx.doi.org/10.3390/ijerph16050883.

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Wastewater discharge is one of the main sources of micropollutants within the aquatic environment. To reduce the risks for the aquatic environment, the reduction of the chemical load of wastewater treatment plant effluent is critical. Based on this need, additional treatment methods, such as ozonation, are currently being tested in several wastewater treatment plants (WWTPs). In the present study, effects were investigated using in situ feeding experiments with Gammarus pulex and body burden analyses of frequently detected micropollutants which used a Quick Easy Cheap Effective Rugged and Safe (QuEChERS) multi-residue method to quantify internal concentrations in collected gammarids. Information obtained from these experiments complemented data from the chemical analysis of water samples and bioassays, which predominantly cover hydrophilic substances. When comparing up- and downstream feeding rates of Gammarus pulex for seven days, relative to the WWTPs, no significant acute effects were detected, although a slight trend of increased feeding rate downstream of the WWTP Aachen-Soers was observed. The chemical load released by the WWTP or at other points, or by diffuse sources, might be too low to lead to clear acute effects on G. pulex. However, some compounds found in wastewater are able to alter the microbial community on its leaves, leading to an increase in the feeding rate of G. pulex. Chemical analysis of internal concentrations of pollutants in the tissues of collected gammarids suggests a potential risk for chronic effects with the chemicals imidacloprid, thiacloprid, carbendazim, and 1H-benzotriazole when exceeding the critical toxic unit value of −3. This study has demonstrated that a combination of acute testing and measurement of the internal concentration of micropollutants that might lead to chronic effects is an efficient tool for investigating river systems, assuming all relevant factors (e.g., species or season) are taken into account.

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Graham, J. "The 2003 R.M. Hardy Lecture: Soil parameters for numerical analysis in clay." Canadian Geotechnical Journal 43, no. 2 (February 1, 2006): 187–209. http://dx.doi.org/10.1139/t05-098.

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Engineers in geotechnical practice work on increasingly complex problems with increasingly powerful numerical tools. Effective solutions to design problems need good information about the site and parameters (or functions) that describe how the soil will behave under the proposed loadings. These loadings can include heating, drying or wetting, time effects, and chemical changes as well as the more common structural loads. This paper outlines issues that need to be considered when laboratory tests are used to produce soil properties for use in numerical analyses. The focus is on soft to moderately stiff saturated clays. Similar considerations for in situ tests, stiff clays, and sands are not considered.Key words: clay, testing, characterization, properties, constitutive modeling.

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Mitas, B., H. Pauna, J. Feldbacher, and J. Schenk. "An In-Situ Analysis Method in EAF and BOF Steelmaking." IOP Conference Series: Materials Science and Engineering 1309, no. 1 (May 1, 2024): 012002. http://dx.doi.org/10.1088/1757-899x/1309/1/012002.

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Abstract An analysis was conducted to gage the feasibility of using a spectroscopic method to determine the chemical composition of the liquid metal phase in EAF and BOF steelmaking. The hypothesis that certain radiation intensities found in UV- and UV-near regions of an spectrum emitted from the hot-spot in the BOF or the impingement area of oxyfuel burners in EAF steelmaking can be used for analysing the chemical components present in the liquid metal is tested. Significant lab-scale experiment results and the conclusions regarding industrial scale implementation are presented.

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Shigenaka, Gary, Buffy Meyer, Edward Overton, and M. Scott Miles. "Physical and Chemical Characterization of In-Situ Burn Residue Encountered by a Deep-Water Fishery in the Gulf of Mexico." International Oil Spill Conference Proceedings 2017, no. 1 (May 1, 2017): 1020–40. http://dx.doi.org/10.7901/2169-3358-2017.1.1020.

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2017-185 ABSTRACT The response technique of in-situ burning was used to great effect during the 2010 Deepwater Horizon oil spill in the Gulf of Mexico. An estimated 220,000-310,000 bbl of surface oil was consumed by operational in-situ burn activities. Post-burn residues were not recovered, as most were denser than seawater and sank after the burns. However, late in 2010, a relatively small deep-water shrimp fishery operating on the shelf north of the Macondo wellhead encountered tarballs on or near the bottom at around 200 m. We physically and chemically characterized samples of these submerged tarballs to confirm them as originating from Deepwater Horizon burns and to understand the features that distinguish them from other residual oil types encountered during the course of the spill response. The chance intersection between a commercial fishery and residues from the in-situ burn operations suggest that the fate of in-situ burn residue should be factored into future spill response tradeoff analyses.

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Buccolieri, Giovanni, Alfredo Castellano, Vito Nicola Iacobelli, Giorgio Giuseppe Carbone, Antonio Serra, Lucio Calcagnile, and Alessandro Buccolieri. "Non-Destructive In Situ Investigation of the Study of a Medieval Copper Alloy Door in Canosa di Puglia (Southern Italy)." Heritage 5, no. 1 (January 8, 2022): 145–56. http://dx.doi.org/10.3390/heritage5010008.

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This paper reports the analyses carried out on the medieval copper alloy door (1111–1118 AD) of the mausoleum of Boemondo d’Altavilla in Canosa di Puglia (Southern Italy). The studied door is the smallest medieval bronze door extant in Italy and, unlike the other Byzantine doors, was most probably made in Canosa di Puglia and not in Constantinople. Analyses were performed to assess the chemical composition of the alloy patinas using a portable energy dispersive X-ray fluorescence (ED-XRF) instrument designed at the University of Salento. The experimental results suggested that the two door leaves have the same chemical composition, even if they appear different in both style and size. Furthermore, the alloy used for the door is different from the other previously-analyzed Byzantine bronze doors. The obtained results can be used in the future to compare the chemical composition of other Byzantine doors in order to better understand the manufacture of these precious artifacts.

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Kuang, Cao, Shuzhong Wang, Ming Luo, and Jun Zhao. "Mechanism Analysis of Coal with CuO in the In Situ Gasification Chemical-Looping Combustion and In Situ Gasification Chemical-Looping with Oxygen Uncoupling Process." Energy & Fuels 35, no. 1 (December 21, 2020): 618–25. http://dx.doi.org/10.1021/acs.energyfuels.0c03242.

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45

Kayode, Sodipo Bashiru, and Azlan Abdul Aziz. "An In-Situ Functionalization of Decanethiol Monolayer on Thin Silica Coated Superparamagnetic Iron Oxide Nanoparticles Synthesized by Non-Seeded Process." Advanced Materials Research 1024 (August 2014): 300–303. http://dx.doi.org/10.4028/www.scientific.net/amr.1024.300.

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Superparamagnetic iron oxide nanoparticles (SPION) are routinely employed in biomedical and water treatment applications due to their inherent magnetic properties. However, for these applications a surface modified and functionalized SPION is required. Herein, for the first time we present an in-situ method of functionalizing decanethiol monolayer on thin silica coated SPION synthesised via a non-seeded process. Through physico-chemical analyses the grafting of decanethiol onto the composite nanoparticles were demonstrated. The alkane functional group in the monolayer molecule attached to the silanol group of the silica shell and became the tail and binding site to the magnetic composite nanoparticles.

46

Yang, Jie, Liping Ma, Jianxiao Tang, Hongpan Liu, Bin Zhu, Yan Lian, and Xiaojing Cui. "Chemical thermodynamics analysis for in-situ gasification chemical looping combustion of lignite with phosphogypsum for syngas." Applied Thermal Engineering 112 (February 2017): 516–22. http://dx.doi.org/10.1016/j.applthermaleng.2016.10.106.

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47

Zhou, Yuqin, Yong Zhang, Ruying Li, Mei Cai, and Xueliang Sun. "One-step in situ synthesis and characterization of W18O49@carbon coaxial nanocables." Journal of Materials Research 24, no. 5 (May 2009): 1833–41. http://dx.doi.org/10.1557/jmr.2009.0214.

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We demonstrate here in situ synthesis of bulk yield W18O49@carbon coaxial nanocables based on an easily controlled chemical vapor deposition process at relatively low temperature (760 °C) using metallic tungsten powder and ethylene (C2H4) as the raw materials. Transmission electron microscope (TEM), energy dispersive x-ray (EDX), and x-ray diffraction (XRD) analyses indicate that the resultant nanostructures are composed of single-crystalline W18O49 nanowires, coaxially covered with amorphous carbon walls. A vapor–solid (VS) mechanism is proposed to interpret the formation of the nanocables. The effect of carbon sources on the nanocable growth was investigated. The results revealed that the introduction of carbon species not only causes the production of W18O49@C nanocable structures, but also obviously modulates growth behaviors and core/shell diameter ratio of the nanocables. The obtained nanocables may find great applications in catalyst systems and optical and electronic nanodevices because of their enhanced surface properties, as well as in high chemical stability.

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Klein, Thomas, Alois Birgmann, and Martin Schnall. "In situ alloying of aluminium-based alloys by (multi-)wire-arc additive manufacturing." MATEC Web of Conferences 326 (2020): 01003. http://dx.doi.org/10.1051/matecconf/202032601003.

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Wire-arc additive manufacturing (WAAM) has received considerable attention in the past years due to advantages in terms of deposition rate, design freedom, buy-to-fly ratio and economic factors. This process can generally be conducted using conventional or near-conventional welding equipment to fabricate intricate but relatively large-scale structures. The present contribution explores options to utilize this novel process not only for manufacturing of particular aluminium structures, but to create the actual alloy composition during processing. Thereby, the possibilities of dual-wire techniques based on cold metal transfer (CMT) to create alloys in the welding process in situ is investigated. For this purpose, a modified CMT twin welding system is used with standard wires differing significantly in their alloying content. The characterization of the chemical compositions at different specimen positions suggests good chemical homogeneity after initial process optimization steps. The microstructural homogeneity is analysed by means of optical light microscopy and scanning electron microscopy. Quantified phase fractions underpin non-equilibrium solidification conditions, when compared to theoretical equilibrium predictions. The assessment of the performed analyses suggests that dual-wire processes are powerful in terms of enhancing achievable depositions rates as well as enabling in situ alloying. This approach might be expandable to multi-wire-based techniques.

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Hazel, G., F. Bucholtz, I. D. Aggarwal, G. Nau, and K. J. Ewing. "Multivariate Analysis of Mid-IR FT-IR Spectra of Hydrocarbon-Contaminated Wet Soils." Applied Spectroscopy 51, no. 7 (July 1997): 984–89. http://dx.doi.org/10.1366/0003702971941359.

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This article describes a series of mid-IR FT-IR reflectance spectroscopy measurements of hydrocarbon-contaminated wet soils. The eventual goal of this work is the development of an analysis tool suitable for real-time in situ underground measurements where a suitable reference spectrum is not available. Multivariate analysis of the resulting spectral data indicates that the strongly varying wet soil matrix and the absence of a suitable reference spectrum in the field do not render this measurement technique unfeasible as a means of realizing remote in situ chemical detection in wet soils. It was also observed that simultaneous quantification of moisture content and identification of soil composition may be achieved. These results have important applications to in situ site characterization for environmental cleanup and soil characterization for construction planning.

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Wilkie, Simeon, Jean Ducasse-Lapeyrusse, Ana Paula Arato Gonçalves, Elisabeth Marie-Victoire, Susan Macdonald, Myriam Bouichou, Nicki Lauder, David Farrell, Paul Gaudette, and Ann Harrer. "Performance evaluation of patch repairs on historic concrete structures (PEPS): a methodology for in situ and laboratory analyses." MATEC Web of Conferences 361 (2022): 04002. http://dx.doi.org/10.1051/matecconf/202236104002.

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While there have been many studies on the performance criteria of concrete patch repairs, there are few specific studies on the long-term performance of patch repairs designed to preserve the aesthetic significance of the original fabric of culturally significant concrete structures. In order to address this issue, the Getty Conservation Institute (GCI), Historic England (HE) and the Laboratoire de Recherche des Monuments Historiques (LRMH) commenced work on an international collaborative research project, ‘Performance Evaluation of Patch Repairs on Historic Concrete Structures’ (PEPS). Begun in 2018, the PEPS project aims to produce practical guidance that will help those repairing historic concrete through the assessment of case studies in the USA, England and France within a variety of climatic and environmental conditions, typologies and repair materials. The operational phases of the research project consist of in situ tests and laboratory analysis performed on both the original concrete and previous patch repairs. This paper provides an overview of the assessment methodology that has been developed by an inter-disciplinary team of professionals working in the field of concrete conservation, and includes a variety of traditional and non-traditional non-destructive, mechanical, chemical, and electro-chemical characterization and diagnostic techniques.

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