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Journal articles on the topic 'K-253'

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Published: 29 July 2024

Last updated: 31 July 2024

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1

Wang, H. J., Sh J. Ma, H. M. Yu, Q. Zhang, Ch M. Guo, and P. Wang. "Thermal Conductivity of Transformer Oil From 253 K to 363 K." Petroleum Science and Technology 32, no. 17 (June 18, 2014): 2143–50. http://dx.doi.org/10.1080/10916466.2012.757235.

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2

Aquino, Leonardo A. de, Fred D. B. da Silva, and Paulo G. Berger. "Características agronômicas e o estado nutricional de cultivares de girassol irrigado." Revista Brasileira de Engenharia Agrícola e Ambiental 17, no. 5 (May 2013): 551–57. http://dx.doi.org/10.1590/s1415-43662013000500013.

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Objetivou-se, neste trabalho, avaliar o estado nutricional, caracteres agronômicos e a produtividade de cultivares de girassol sob irrigação. Os cultivares Embrapa 122 V-2000, Hélio 250, Hélio 251, Hélio 253, Hélio 358, Hélio 360, IAC Iarama, Dow Agroscience M 734 e MG 02, foram semeados em blocos ao acaso, com quatro repetições. O número de folhas por planta no florescimento foi maior nos híbridos Hélio 250, Hélio 251, Hélio 253, Hélio 358, Hélio 360, Dow Agroscience M 734 e MG 02, em relação aos cultivares de polinização aberta Embrapa 122 V-2000 e IAC Iarama. Os teores foliares de N, P, K, Ca, Mg e S foram 40,91; 3,51; 35,91; 33,91; 6,23 e 7,88 g kg-1, respectivamente. Os cultivares Embrapa 122 V-2000 e IAC-Iarama apresentaram teor de P na folha índice menor que os demais cultivares. Os teores foliares de Zn, Cu, Fe e o Mn foram 75,15; 24,11; 98,39 e 348,10 mg kg-1, respectivamente. O teor médio de B na folha índice nos híbridos e nas variedades de polinização aberta foi de 119,25 e 140,35 mg kg-1, respectivamente. Os cultivares Hélio 250, Hélio 251, Hélio 253, Hélio 358, Hélio 360, Dow Agroscience M 734 e MG 02 apresentaram maior produtividade que o Embrapa 122 V-2000 e o IAC Iarama.

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3

Ulrich, T., M. Ammann, S. Leutwyler, and T. Bartels-Rausch. "The adsorption of peroxynitric acid on ice between 230 K and 253 K." Atmospheric Chemistry and Physics Discussions 11, no. 9 (September 28, 2011): 26815–48. http://dx.doi.org/10.5194/acpd-11-26815-2011.

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Abstract. Peroxynitric acid uptake to ice and snow has been proposed to be a major loss process from the atmosphere with impacts on the atmospheric oxidation capacity. Here we present results from a laboratory study on the interaction of peroxynitric acid with water ice at low concentrations. Experiments were performed in a coated wall flow tube at atmospheric pressure and in the environmentally relevant temperature range of 230 K to 253 K. The interaction was found to be fully reversible and decomposition was not observed. Analysis based on the Langmuir adsorption model showed that the partitioning of peroxynitric acid to ice is orders of magnitude lower than of nitric acid and similar to nitrous acid partitioning behavior. The partition coefficient (KLinC) and its temperature dependency can be described by 3.74×10−12×e(7098/T) [cm]. Atmospheric implications are discussed and show that the uptake to cirrus clouds or to snow-packs in polar areas is an important sink for peroxynitric acid in the environment.

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4

Ulrich, T., M. Ammann, S. Leutwyler, and T. Bartels-Rausch. "The adsorption of peroxynitric acid on ice between 230 K and 253 K." Atmospheric Chemistry and Physics 12, no. 4 (February 17, 2012): 1833–45. http://dx.doi.org/10.5194/acp-12-1833-2012.

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Abstract. Peroxynitric acid uptake to ice and snow has been proposed to be a major loss process from the atmosphere with impacts on the atmospheric oxidation capacity. Here we present results from a laboratory study on the interaction of peroxynitric acid with water ice at low concentration. Experiments were performed in a coated wall flow tube at atmospheric pressure and in the environmentally relevant temperature range of 230 K to 253 K. The interaction was found to be fully reversible and decomposition was not observed. Analysis based on the Langmuir adsorption model showed that the partitioning of peroxynitric acid to ice is orders of magnitude lower than of nitric acid and similar to nitrous acid partitioning behavior. The partition coefficient (KLinC) and its temperature dependency can be described by 3.74 × 10−12 × e(7098/T) [cm]. Atmospheric implications are discussed and show that the uptake to cirrus clouds or to snow-packs in polar areas is an important sink for peroxynitric acid in the environment.

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5

Bora, Neharika Malhotra, Ruchika Garg, S. Shantha Kumari, Kiranmai Devineni, and Vishi Agrawal. "CoQ10-Mitochondrial Energizer in Ageing Oocytes and female infertility." Journal of South Asian Federation of Obstetrics and Gynaecology 8, no. 4 (2016): 253–55. http://dx.doi.org/10.5005/jp-journals-10006-1429.

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How to cite this article detail Garg R, Bora NM, Agrawal V, Kumari SS, Devineni K. CoQ10-Mitochondrial Energizer in Ageing Oocytes and female infertility. J South Asian Feder Obst Gynae 2016;8(4):253-255.

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6

Duan, Yuan-Yuan, Lin Shi, Li-Zhong Han, and Ming-Shan Zhu. "Viscosity of saturated liquid trifluoroiodomethane from 253 to 338 K." Fluid Phase Equilibria 162, no. 1-2 (August 1999): 303–12. http://dx.doi.org/10.1016/s0378-3812(99)00216-2.

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7

Tillmann, R., M. Hallquist, Å. M. Jonsson, A. Kiendler-Scharr, H. Saathoff, Y. Iinuma, and Th F. Mentel. "Influence of relative humidity and temperature on the production of pinonaldehyde and OH radicals from the ozonolysis of α-pinene." Atmospheric Chemistry and Physics Discussions 10, no. 2 (February 5, 2010): 3129–72. http://dx.doi.org/10.5194/acpd-10-3129-2010.

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Abstract. The ozonolysis of α-pinene has been investigated under dry and humid conditions in the temperature range of 243–303 K. The results provided new insight into the role of water and temperature in the degradation mechanism of α-pinene and in the formation of secondary organic aerosols (SOA). The SOA yields were higher at humid conditions than at dry conditions. The water induced gain was largest for the lowest temperatures investigated (243 and 253 K). The increase in the SOA yields was dominated by water (and temperature) effects on the organic product distribution, whilst physical uptake of water was negligible. This will be demonstrated for the example of pinonaldehyde (PA) which was formed as a~major product in the humid experiments with total molar yields of 0.30±0.06 at 303 K and 0.15±0.03 at 243 K. In the dry experiments the molar yields of PA were only 0.07±0.02 at 303 K and 0.02±0.02 at 253 K. The observed partitioning of PA as a function of the SOA mass present at 303 K limited the effective vapour pressure of pure PA pPA0 to the range of 0.01–0.001 Pa, 3–4 orders of magnitude lower than literature values. The corresponding mass partitioning coefficient was determined to KPA=0.005±0.004 m3/μg and the total mass yield αPA.total=0.37±0.08. At 303 K PA preferably stayed in the gas-phase, whereas at 253 K and 243 K it exclusively partitioned into the particulate phase. PA could thus account at least for half of the water induced gain in SOA mass at 253 K. The corresponding effect was negligible at 303 K because the PA preferably remained in the gas-phase. The yield of OH radicals, which were produced in the ozonolysis, was indirectly determined by means of the yield of cyclohexanone formed in the reaction of OH radicals with cyclohexane. OH yields of the α-pinene ozonolysis were determined to 0.67±0.17 for humid and 0.54±0.13 for dry conditions at 303 K, indicating a water dependent path of OH radical formation. For 253 and 243 K OH yields could be estimated to 0.5 with no significant difference between the dry and humid experiments. This is the first clear indication for OH radical formation by α-pinene ozonolysis at such low temperatures.

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8

Tillmann, R., M. Hallquist, Å. M. Jonsson, A. Kiendler-Scharr, H. Saathoff, Y. Iinuma, and Th F. Mentel. "Influence of relative humidity and temperature on the production of pinonaldehyde and OH radicals from the ozonolysis of α-pinene." Atmospheric Chemistry and Physics 10, no. 15 (August 3, 2010): 7057–72. http://dx.doi.org/10.5194/acp-10-7057-2010.

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Abstract. The ozonolysis of α-pinene has been investigated under dry and humid conditions in the temperature range of 243–303 K. The results provided new insight into the role of water and temperature in the degradation mechanism of α-pinene and in the formation of secondary organic aerosols (SOA). The SOA yields were higher at humid conditions than at dry conditions. The water induced gain was largest for the lowest temperatures investigated (243 and 253 K). The increase in the SOA yields was dominated by water (and temperature) effects on the organic product distribution, whilst physical uptake of water was negligible. This will be demonstrated for the example of pinonaldehyde (PA) which was formed as a major product in the humid experiments with total molar yields of 0.30±0.06 at 303 K and 0.15±0.03 at 243 K. In the dry experiments the molar yields of PA were only 0.07±0.02 at 303 K and 0.02±0.02 at 253 K. The observed partitioning of PA as a function of the SOA mass present at 303 K limited the effective vapour pressure of pure PA pPA0 to the range of 0.01–0.001 Pa, 3–4 orders of magnitude lower than literature values. The corresponding mass partitioning coefficient was determined to KPA=0.005±0.004 m3 μg−1 and the total mass yield αPAtotal=0.37±0.08. At 303 K PA preferably stayed in the gas-phase, whereas at 253 K and 243 K it exclusively partitioned into the particulate phase. PA could thus account at least for half of the water induced gain in SOA mass at 253 K. The corresponding effect was negligible at 303 K because the PA preferably remained in the gas-phase. The yield of OH radicals, which were produced in the ozonolysis, was indirectly determined by means of the yield of cyclohexanone formed in the reaction of OH radicals with cyclohexane. OH yields of the α-pinene ozonolysis were determined to 0.67±0.17 for humid and 0.54±0.13 for dry conditions at 303 K, indicating a water dependent path of OH radical formation. For 253 and 243 K OH yields could be estimated to 0.5 with no significant difference between the dry and humid experiments. This is the first clear indication for OH radical formation by α-pinene ozonolysis at such low temperatures.

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9

Guzei, Ilia A., Lara C. Spencer, Joe W. Su, and Ronald R. Burnette. "Low-temperature enantiotropic k2 phase transition in the ionic 222-cryptand complex with LiClO4." Acta Crystallographica Section B Structural Science 63, no. 1 (January 15, 2007): 93–100. http://dx.doi.org/10.1107/s0108768106044831.

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Crystallographic analyses at 100 and 200 K are reported for the macrobicyclic polyether 4,7,13,16,21,24-hexaoxa-1,10-diaza-bicyclo[8.8.8]hexacosane (denoted as 222-cryptand) that encapsulates a Li+ cation and then forms a complex (I) with ClO_4^-. Compound (I) undergoes a reversible second-order k phase transition at 253 (2) K from an almost ordered structure [space group P212121] at 100 K to a more disordered structure that exhibits a different unit cell [P21212 (2c′ = c)] above 253 (2) K. At 295 K the Li+ cation and five atoms of the perchlorate anion are each disordered over at least two positions about a crystallographic twofold axis [Chekhlov (2003). Russ. J. Coord. Chem. 29, 828–832]; as the temperature decreases the dynamic positional disorder is slowly frozen out, but is still observed for lithium even at 100 K. Based upon DFT computations, it seems that in the solid state the position of the Li+ cation in the cavity of the 222-cryptand below 253 (2) K likely corresponds to a local energy minimum; the global minimum in the gas phase corresponds to a near D 3 symmetrical conformation of the 222-cryptand with the undersized Li+ cation residing in the center of its cavity.

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10

Katada, Motomi, Dilara Afroj, Takashi Yamauchi, and Satoshi Kawata. "Mössbauer Spectroscopic Studies of (Me2NH2)2SnX6 (X = Cl or Br) and Their Related Complexes." Zeitschrift für Naturforschung A 57, no. 6-7 (July 1, 2002): 607–12. http://dx.doi.org/10.1515/zna-2002-6-758.

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The temperature dependence in the 119Sn Mössbauer spectral area for {(CH3)2NH2}2SnCl6 was found to be almost linear, although a phase transition of the complex has been suggested by IR, 35Cl NQR and NMRstudies, while an anomaly in the temperature dependence for {(CH3)2NH2}2SnBr6 was found at 235 K, which is close to the phase transition temperature 253 K determined by 89Br NQR. These differences are attributable to molecular motion of the dimethylammonium ion in the complexes. The X-ray powder diffraction pattern of {(CH3)2NH2}2SnCl6 did not change near the phase transition point, but that of {(CH3)2NH2}2SnBr6 changed at 108 - 123 K and 233 - 253 K

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11

Shamberger, Patrick J., and Timothy Reid. "Thermophysical Properties of Lithium Nitrate Trihydrate from (253 to 353) K." Journal of Chemical & Engineering Data 57, no. 5 (April 10, 2012): 1404–11. http://dx.doi.org/10.1021/je3000469.

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12

Mitsuishi, Ikuyuki, Noriko Y. Yamasaki, and Yoh Takei. "Fe K LINE COMPLEX IN THE NUCLEAR REGION OF NGC 253." Astrophysical Journal 742, no. 2 (November 11, 2011): L31. http://dx.doi.org/10.1088/2041-8205/742/2/l31.

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13

Kong, Chunli, Caiping Duan, Yixuan Zhang, Ce Shi, and Yongkang Luo. "Changes in Lipids and Proteins of Common Carp (Cyprinus carpio) Fillets under Frozen Storage and Establishment of a Radial Basis Function Neural Network (RBFNN)." Foods 12, no. 14 (July 19, 2023): 2741. http://dx.doi.org/10.3390/foods12142741.

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Storage via freezing remains the most effective approach for fish preservation. However, lipid oxidation and protein denaturation still occur during storage, along with nutritional loss. The extent of lipid alteration and protein denaturation are associated with human health defects. To precisely predict common carp (Cyprinus carpio) nutritional quality change during frozen storage, here, we first determined lipid oxidation and hydrolysis and protein denaturation of common carp fillets during 17 weeks of frozen preservation at 261 K, 253 K, and 245 K. Results showed that the content of thiobarbituric acid reactive substances (TBARS) and free fatty acids (FFA) were significantly increased. However, salt-soluble protein (SSP) content, Ca2+-ATPase activity, and total sulfhydryl (SH) content kept decreasing during frozen storage, with SSP content decreasing by 64.82%, 38.14%, and 11.24%, respectively, Ca2+-ATP enzyme activity decreasing to 12.50%, 18.52%, and 28.57% Piμmol/mg/min, and SH values decreasing by 70.71%, 64.92%, and 56.51% at 261 K, 253 K, and 245 K, respectively. The values at 261 K decreased more than that at 253 K and 245 K (p < 0.05). Ca2+-ATPase activity was positively correlated (r = 0.96) with SH content. Afterwards, based on the results of the above chemical experiments, we developed a radial basis function neural network (RBFNN) to predict the modification of lipid and protein of common carp fillets during frozen storage. Results showed that all the relative errors of experimental and predicted values were within ±10%. In summary, the quality of common carp can be well protected at 245 K, and the established RBFNN could effectively predict the quality of the common carp under frozen conditions at 261–245 K.

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14

Sánchez, T., José Luis Sánchez Llamazares, B. Hernando, J. D. Santos, M. L. Sánchez, M. J. Perez, Joan Josep Suñol, Reiko Sato Turtelli, and Roland Grössinger. "Annealing Effect on Martensitic Transformation and Magneto-Structural Properties of Ni-Mn-In Melt Spun Ribbons." Materials Science Forum 635 (December 2009): 81–87. http://dx.doi.org/10.4028/www.scientific.net/msf.635.81.

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We report the effect of a short-time vacuum annealing (1073 K during 10 minutes) on structural phase transition temperatures and magneto-structural properties of as-quenched ribbons of the Heusler alloy Ni50.6Mn34.5In14.9. This alloy crystallizes in a single phase cubic B2-type austenite with a Curie point of TCA=284 K that with the lowering in temperature transforms into a martensite with TCM185 K. The direct and reverse martensitic phase transition temperatures were MS=257 K, Mf = 221 K, AS = 239 K, and Af = 266 K. After annealing austenite shows the highly ordered L21-type structure while the average chemical composition as well as the structural and magnetic transition temperatures were shifted to Ni50.2Mn34.3In15.5 and MS = 253 K, Mf = 238 K, AS = 257 K, Af = 265 K, ΔT = 13 K, TCA = 299 K and TCM207 K. In the annealed samples the magnetization changes associated to the magnetic and structural transitions are more abrupt and magnetization isotherms in both the austenitic and martensitic existence region show higher initial magnetic susceptibility and faster approach to saturation. Field-cooled hysteresis loops at 10 K were shifted along the negative H-axis for both samples, but a significant anomaly was evident on the left side of the hysteresis loop for as-quenched ribbons.

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15

Maqsood, Asghari, Iftikhar Hussain Gul, and M. Anis-ur-Rehman. "Thermal transport properties of granites in the temperature range 253–333 K." Journal of Physics D: Applied Physics 37, no. 9 (April 15, 2004): 1405–9. http://dx.doi.org/10.1088/0022-3727/37/9/016.

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16

Mironenko, Mikhail V., Ginger E. Boitnott, Steven A. Grant, and Ronald S. Sletten. "Experimental Determination of the Volumetric Properties of NaCl Solutions to 253 K." Journal of Physical Chemistry B 105, no. 41 (October 2001): 9909–12. http://dx.doi.org/10.1021/jp011356f.

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17

Kenebayev, A. T., S. T. Yerzhanova, M. A. Yesimbekova, S. S. Abayev, and B. B. Kalibayev. "FERTILITY OF ALFALFA VARIETIES IN SELF-POLLINATION AND CROSS-POLLINATION." Bulletin of the Korkyt Ata Kyzylorda University 63 (2022): 160–69. http://dx.doi.org/10.52081/bkaku.2022.v63.i4.140.

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The article presents the results of studying alfalfa in a collection nursery by fertility, self-fertility, number of seeds in one pod, percentage of fertility of seedbuds in the ovary, number of seedbuds in one flower and seed productivity. The goal of the research is to study self-pollination and cross-pollination, fertility of a collection of alfalfa cultivars of different ecological and geographical origin to apply the best varieties in breeding process. All the experiments carried out at the «LLP Kazakh Research Institute of Agriculture and Plant» study area. We involved 134 varieties of alfalfa, sowing (M. sativa L) and changing alfalfa (M. varia Mart) of domestic and foreign breeding from 18 countries of the world. Due to the increasing interest in the development of synthetic and partially self-pollinated varieties of alfalfa, there has been a lot of attention paid to this issue. In the south-east of Kazakhstan, alfalfa forms 22-49% of pods from the number of observed flowers in a freely accessible state for pollinators. Alfalfa seed productivity depends significantly on seed setting per flower. The specimens from Ukraine (k-450), Turkmenistan (k-253) and France (k-315) had fertility levels between 67,3 and 72,1 % in the conditions of south-east Kazakhstan. The index of pod setting during cross-pollination in all varieties persuasively exceeds in 3 - 5 times the level of pod setting during self-pollination under isolators. Self-fertility in specimens varied in the organic range of 8,4 - 14,2 %. One of the major criteria determining the level of seed productivity is seed yield per pod, this index stood out varieties: from Sweden (k-356), Ukraine (k-450), Turkmenistan (k-253) and France (k-315). The yield of seeds per pod reached 3.5 - 4.3 (0 of 7). All in all, the specimen from France (k-315) differed by high rates of seed yield. Seed yield reached 47.3 g/m2, which exceeded the standard by 36.3%. Besides, US (k-365), Ukraine (k-450), Turkmenistan (k-253), Russia (k-473) showed good results, where the excess under the standard was 15.2 % - 21.9 %.

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18

Schlosser, Gerhard. "Understanding evolution Kampourakis, K. ( 2014) Understanding evolution. Cambridge: Cambridge Univ. Press, p. 253." Evolution & Development 18, no. 2 (February 12, 2016): 144–45. http://dx.doi.org/10.1111/ede.12176.

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19

Takeya, Satoshi, Akio Yoneyama, Kazuhiro Ueda, Hiroko Mimachi, Masahiro Takahashi, Kenichi Sano, Kazuyuki Hyodo, Tohoru Takeda, and Yoshito Gotoh. "Anomalously Preserved Clathrate Hydrate of Natural Gas in Pellet Form at 253 K." Journal of Physical Chemistry C 116, no. 26 (June 20, 2012): 13842–48. http://dx.doi.org/10.1021/jp302269v.

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20

Pandey, Ajit Kumar. "Book review: Debel K. Singha Roy, Identity, Society and Transformative Social Categories: Dynamics of Construction, Configuration and Contestation." Sociological Bulletin 68, no. 2 (July 2019): 248–50. http://dx.doi.org/10.1177/0038022919848971.

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Debel K. Singha Roy, Identity, Society and Transformative Social Categories: Dynamics of Construction, Configuration and Contestation. New Delhi: SAGE Publications, 2018, 253 pp., ₹795 (Paperback). ISBN: 978-93-528-0462-7.

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21

Lapaev, Dmitry V., Victor G. Nikiforov, Vladimir S. Lobkov, Andrey A. Knyazev, and Yury G. Galyametdinov. "A photostable vitrified film based on a terbium(iii) β-diketonate complex as a sensing element for reusable luminescent thermometers." Journal of Materials Chemistry C 6, no. 35 (2018): 9475–81. http://dx.doi.org/10.1039/c8tc01288a.

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A highly efficient sensing element based on a photostable vitrified film of the terbium(iii) β-diketonate complex for reusable luminescent thermometers suitable for long-term monitoring in the range of 143–253 K.

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22

Horie, O., and G. K. Moortgat. "Photolysis of Ketene-Oxygen Mixtures between 253 K and 323 K in Relation to the Formation of Criegee Intermediates." Berichte der Bunsengesellschaft für physikalische Chemie 96, no. 3 (March 1992): 404–8. http://dx.doi.org/10.1002/bbpc.19920960332.

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23

Zhang, Yin-Qiang, Guan-Cheng Xu, and Yan Luo. "(C₂H₅NH₃)₃[InBr₆]: an indium(iii) organic–inorganic hybrid phase transition compound exhibiting a switchable dielectric response." New Journal of Chemistry 45, no. 43 (2021): 20140–43. http://dx.doi.org/10.1039/d1nj03814a.

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The organic–inorganic hybrid compound (C2H5NH3)3[InBr6] undergoes a phase transition at 248/253 K, and exhibits a switchable dielectric response. The phase transition is associated with the order–disorder changes of ethylammonium cations.

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24

Okayasu, Yoshinori, Hajime Kamebuchi, and Junpei Yuasa. "The effect of ligand symmetry on the ratiometric luminescence characteristics of lanthanides." Dalton Transactions 47, no. 19 (2018): 6779–86. http://dx.doi.org/10.1039/c8dt00898a.

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Nona-coordinated europium(iii) complexes incorporating unsymmetrical β-diketonate ligands exhibit distinctive ratiometric spectral changes within the extremely narrow f–f transition bands in response to temperature changes over the range from 253 to 323 K.

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25

Tanaka, Kunihiko, Jeffrey G. Mangum, Serena Viti, Sergio Martín, Nanase Harada, Kazushi Sakamoto, Sebastien Muller, et al. "Volume Density Structure of the Central Molecular Zone NGC 253 through ALCHEMI Excitation Analysis." Astrophysical Journal 961, no. 1 (January 1, 2024): 18. http://dx.doi.org/10.3847/1538-4357/ad0e64.

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Abstract We present a spatially resolved excitation analysis for the central molecular zone (CMZ) of the starburst galaxy NGC 253 using the data from the Atacama Large Millimeter/submillimeter Array Comprehensive High-resolution Extragalactic Molecular Inventory, whereby we explore parameters distinguishing NGC 253 from the quiescent Milky Way’s Galactic center (GC). Non-LTE analyses employing a hierarchical Bayesian framework are applied to Band 3–7 transitions from nine molecular species to delineate the position–position–velocity distributions of column density ( N H 2 ), volume density ( n H 2 ), and temperature (T kin) at 27 pc resolution. Two distinct components are detected: a low-density component with ( n H 2 , T kin ) ∼ ( 10 3.3 cm − 3 , 85 K ) and a high-density component with ( n H 2 , T kin ) ∼ ( 10 4.4 cm − 3 , 110 K ) , separated at n H 2 ∼ 10 3.8 cm − 3 . NGC 253 has ∼10 times the high-density gas mass and ∼3 times the dense-gas mass fraction of the GC. These properties are consistent with their HCN/CO ratio but cannot alone explain the factor of ∼30 difference in their star formation efficiencies (SFEs), contradicting the dense-gas mass to star formation rate scaling law. The n H 2 histogram toward NGC 253 exhibits a shallow declining slope up to n H 2 ∼ 10 6 cm − 3 , while that of the GC steeply drops in n H 2 ≳ 10 4.5 cm − 3 and vanishes at 105 cm−3. Their dense-gas mass fraction ratio becomes consistent with their SFEs when the threshold n H 2 for the dense gas is taken at ∼104.2−4.6 cm−3. The rich abundance of gas above this density range in the NGC 253 CMZ, or its scarcity in the GC, is likely to be the critical difference characterizing the contrasting star formation in the centers of the two galaxies.

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26

Heathfield, A. E., C. Anastasi, J. Ballard, D. A. Newnham, and A. McCulloch. "Integrated infrared absorption coefficients of CF3OCF2H and CH3OCF2CF2H at 297, 253 and 213 K." Journal of Quantitative Spectroscopy and Radiative Transfer 59, no. 1-2 (January 1998): 91–97. http://dx.doi.org/10.1016/s0022-4073(97)00166-0.

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27

Кузнецов, Д. Д., Е. И. Кузнецова, А. В. Маширов, А. С. Лошаченко, Д. В. Данилов, Г. А. Шандрюк, В. Г. Шавров, and В. В. Коледов. "In situ TEM-исследование фазовых превращений в нестехиометрическом сплаве Гейслера Ni-=SUB=-46-=/SUB=-Mn-=SUB=-41-=/SUB=-In-=SUB=-13-=/SUB=-." Физика твердого тела 63, no. 11 (2021): 1725. http://dx.doi.org/10.21883/ftt.2021.11.51568.10s.

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This paper presents a study of the metamagnetostructural transition of the martensitic type in the Ni46Mn41In13 alloy with magnetic shape memory and inverse magnetocaloric effect. The characteristic temperatures of the direct transition starting Ms = 253 K and its finishing Mf = 164 K, as well as the reverse temperatures As = 203 K and Af = 236 K, respectively, were determined by differential scanning calorimetry. The characteristic peculiarities of the transition: a decrease of the Ms and the presence of a residual austenite phase, as well as pre-martensitic states, were studied using transmission electron microscopy. The estimated the thickness of alloy was 50 nm, when martensitic transition suppressed.

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Zhang, Chuhang. "Fabricating Dispersed Fine Silver Nanoparticles on Liquid Substrate for Improved Photocatalytic Water Splitting Efficiency." Catalysts 13, no. 6 (May 28, 2023): 946. http://dx.doi.org/10.3390/catal13060946.

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Dispersed silver nanoparticles (NPs) are synthesized on a silicone oil substrate under varied substrate temperature T by thermal vaporization method. Scanning electron microscopic investigation demonstrates that the mean size of the NPs are around 7.8 nm with a standard deviation of 1.0 nm. The NPs are transferred to a strontium titanate (STO) crystal as co-catalyst for water splitting efficiency test. The photoelectrochmical (PEC) measurement reveals the photocatalytic activity of NP co-catalyst sensitively relies on T during deposition process: the relative current density jr increases from 4.8 μA/cm2 to 25.4 μA/cm2 as T goes up from 253 K to 333 K. However, a slight decrease of jr from 25.4 μA/cm2 to 22.8 μA/cm2 is found as T further increases to 353 K. The dependent behavior of jr on T is explained in term of a competition mechanism between microstructure evolution and growth model of the NPs under different T: for T ranging from 253 K to 333 K, the effect of a higher crystalline structure for NPs fabricated under higher T improves the electron transfer rate from STO to NPs is dominant. As T increases to 353 K, the overlapping of NPs become a factor for photocatalytic activity of NP/STO system: the diffusion distance of electrons becomes larger and the apparent contact area between NPs and STO is reduced which in turn reduce the photocatalytic activity of NP/STO. The experimental method to synthesize NPs in this report may open up a way to further apply fine NPs in enhancing photocatalytic water splitting efficiency.

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29

Stefańczyk, Olaf, Anna M. Majcher, Michał Rams, Wojciech Nitek, Corine Mathonière, and Barbara Sieklucka. "Photo-induced magnetic properties of the [CuII(bapa)]2[MoIV(CN)8]·7H2O molecular ribbon." Journal of Materials Chemistry C 3, no. 33 (2015): 8712–19. http://dx.doi.org/10.1039/c5tc01889g.

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A novel 1-D photomagnetic L-Cu^II–[Mo^IV(CN)₈]⁴⁻ complex was obtained, in which the photomagnetic effect is fully reversible by heating above 253 K, and partially reversible by irradiation with red and infrared light.

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30

Feng, Yijun, Jincheng Zhang, Yongbing Pei, Qiu Chen, Yue Yan, and Lianbin Wu. "A Novel Strategy to Tune Magnetic Properties of Nickel(II)-Schiff Base Coordination Bridged Polysilsesquioxane." Science of Advanced Materials 11, no. 12 (December 1, 2019): 1705–11. http://dx.doi.org/10.1166/sam.2019.3600.

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In this paper, liquid state solvent-free organosilica-based nickel-bithiazole complexes (PBSIBTHM-Ni2+, PBSIBTMeM-Ni2+) were synthesized through sol–gel processes respectively, and these two metal complexes and their precursors were characterized. The precursors with bithiazole were successfully prepared, their inorganic and organic parts were connected on molecular level. The DSC results indicated they would all exist in liquid phase at temperature ranging from 180 K to 280 K. The UV-VIS showed that a red shift of the main electronic transitions from 254 to 268 nm of PBSIBTHM to PBSIBTHM-Ni2+, Δν = 14 (from 249 to 266 nm of PBSIBTMeM to PBSIBTMeM-Ni2+, Δν = 17). This verified the formation of a more extensive π→π* conjugating system due to coordination interaction between Ni2+ and PBSIBTHM or PBSIBTMeM. The magnetic measurement results of PBSIBTHM-Ni2+ and PBSIBTMeM-Ni2+ reflected they both exhibited ferromagnetic properties at low temperature. For PBSIBTMeM-Ni2+, it had a transition temperature (Ttran) at 160 K, and became an anti-ferromagnet above Ttran. For PBSIBTHM-Ni2+, it had a very high Curie-Weiss temperature (Tc = 253 K). This strategy was expected to find potential application in fabricating the complexes with desired physicochemical properties.

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31

Cernik, R. J., S. R. Craig, K. J. Roberts, and J. N. Sherwood. "A near-ambient-temperature-control cell for use with synchrotron X-ray powder diffraction." Journal of Applied Crystallography 28, no. 5 (October 1, 1995): 651–53. http://dx.doi.org/10.1107/s0021889895003979.

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A low-cost cell has been designed and built for synchrotron X-ray powder diffraction studies of materials with low melting points. The cell has been operated between 253 and 323 K with a temperature stability of better than 0.1 K. The construction of the cell allows free rotation of the sample during a scan in order to maximize the number of powder grains in the reflecting position. The cell has been used to study a transition from an ordered to a rotator phase in hexadecane occurring at 278 K and the results from that study are reported.

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32

Kuznetsov D. D., Kuznetsova E. I., Mashirov A. V., Loshachenko A. S., Danilov D. V., Shandryuk G. A., Shavrov V. G., and Koledov V. V. "In situ TEM study of phase transformations in nonstoichiometric Ni-=SUB=-46-=/SUB=-Mn-=SUB=-41-=/SUB=-In-=SUB=-13-=/SUB=- Heusler alloy." Physics of the Solid State 63, no. 13 (2022): 1593. http://dx.doi.org/10.21883/pss.2022.13.52296.10s.

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This paper presents a study of the metamagnetostructural transition of the martensitic type in the Ni46Mn41In13 alloy with magnetic shape memory and inverse magnetocaloric effect. The characteristic temperatures of the direct transition starting M_s=253 K and its finishing M_f=164 K, as well as the reverse temperatures A_s=203 K and A_f=236 K, respectively, were determined by differential scanning calorimetry. The characteristic peculiarities of the transition: a decrease of the Ms and the presence of a residual austenite phase, as well as pre-martensitic states, were studied using transmission electron microscopy. The estimated the thickness of alloy was 50 nm, when martensitic transition suppressed. Keywords: martensitic transformation, metamagnetostructural transformation, premartensitic states.

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Kuznetsov D. D., Kuznetsova E. I., Mashirov A. V., Loshachenko A. S., Danilov D. V., Shandryuk G. A., Shavrov V. G., and Koledov V. V. "In situ TEM study of phase transformations in nonstoichiometric Ni-=SUB=-46-=/SUB=-Mn-=SUB=-41-=/SUB=-In-=SUB=-13-=/SUB=- Heusler alloy." Physics of the Solid State 63, no. 13 (2022): 2063. http://dx.doi.org/10.21883/pss.2022.13.54528.10s.

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This paper presents a study of the metamagnetostructural transition of the martensitic type in the Ni46Mn41In13 alloy with magnetic shape memory and inverse magnetocaloric effect. The characteristic temperatures of the direct transition starting M_s=253 K and its finishing M_f=164 K, as well as the reverse temperatures A_s=203 K and A_f=236 K, respectively, were determined by differential scanning calorimetry. The characteristic peculiarities of the transition: a decrease of the Ms and the presence of a residual austenite phase, as well as pre-martensitic states, were studied using transmission electron microscopy. The estimated the thickness of alloy was 50 nm, when martensitic transition suppressed. Keywords: martensitic transformation, metamagnetostructural transformation, premartensitic states.

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Edelmann, R., A. Würflinger, S. v. Hornhardt, and M. Stockhausen. "The Room Temperature Dielectric Spectrum of 2,2-Dimethyl-1 -butanol." Zeitschrift für Naturforschung A 48, no. 12 (December 1, 1993): 1231–33. http://dx.doi.org/10.1515/zna-1993-1214.

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Abstract The dielectric spectrum of the title substance ('neohexanol') in its pure liquid state is reported for 293 K up to 71 GHz and, for a restricted frequency range, also for lower temperatures (down to 253 K). The room temperature spectrum resembles that of alicyclic alcohols, in particular cyclopentanol, with respect to spectral shape, main relaxation time and the relation of the latter to viscosity, which similarity may be connected with the fact that these alcohols are able to form 'plastic crystals'.

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35

Banares-Munoz, M. A., and V. Sanchez Escribano. "Adsorption isotherms of nitrogen at 77 and 87 K and n-butane at 236, 253, and 273 K onto tungsten disulfide." Langmuir 7, no. 8 (August 1991): 1779–83. http://dx.doi.org/10.1021/la00056a034.

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36

Adamczewski, Przemysław. "Timirlan Aytberov, K istorii avarcev Tersko-Sulakskogo meždureč’ja, Makhachkala: “Fond Duxovnoe Nasledie”, 2015.—253 pp." Iran and the Caucasus 22, no. 1 (May 15, 2018): 116–18. http://dx.doi.org/10.1163/1573384x-20180110.

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37

Lin, Hong, and Yuan-Yuan Duan. "Surface Tension of Difluoromethane (R-32) + 1,1,1,2,3,3,3-Heptafluoropropane (R-227ea) from (253 to 333) K." Journal of Chemical & Engineering Data 50, no. 1 (January 2005): 182–86. http://dx.doi.org/10.1021/je049743g.

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38

Suzuki, E., H. Kabasawa, T. Honma, R. Nozaki, and Y. Shiozaki. "Temperature dependence of crystal structure of NaK0.72(NH4)0.28(+)-C4H4O6.4H2O in the paraelectric phase." Acta Crystallographica Section B Structural Science 52, no. 6 (December 1, 1996): 976–81. http://dx.doi.org/10.1107/s0108768196005502.

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The crystal structures of the ferroelectric NaK0.72 (NH4)0.28(+)-C4H4O6.4H2O (RS0.72ARS0.28) have been studied in the paraelectric phase [Mr = 276.32, orthorhombic, P21212,° Z = 4, F(000) = 575.04, λ(Mo Kα1) = 0.70926 Å]; T = 213 (1), 253 (1) and 293 (1) K. The crystal data are as follows: (I) at T = 213 (1) K: R = 0.0424, wR = 0.0399, number of reflections = 3414, a = 11.899 (2), b = 14.273 (2), c = 6.211 (1) Å, V = 1054.9 (2) Å3, Dx = 1.740 g cm−3; (II) at T = 253 (1) K: R = 0.0498, wR = 0.0442, number of reflections = 3284, a = 11.929 (1), b = 14.297 (1), c = 6.221 (1) Å, V = 1061.0 (2) Å3, Dx = 1.730 g cm−3; (III) at T = 293 (1) K: R = 0.0473, wR = 0.0392, number of reflections = 3179, a = 11.955 (1), b = 14.317 (1), c = 6.231 (1) Å, V = 1066.5 (1) Å3, Dx = 1.721 g cm−3. X-ray investigations reveal details of structural change with temperature in the paraelectric phase. The carboxylate anion O(3)—C(4)—O(4) in the tartrate molecule is displaced along the a axis as the temperature decreases; moreover, the O(8) atom is displaced in the opposite direction against the shift of the carboxylate anion. The temperature dependence of the thermal motions of O(8) shows different behavior from the other O atoms of the water molecules. The amplitude of the thermal motion of O(8) does not tend to zero at T = 0 K, while the other O atoms of the water molecules tend to zero.

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39

Jarraya, Khaled, Taher Mhiri, and Xavier Le Goff. "Dehydration and decomposition behavior of the NaH2(PO4)0,48AsO4)0,52.H2O compound in the temperature range from 253 K to 333 K." JOURNAL OF ADVANCES IN CHEMISTRY 10, no. 3 (July 31, 2014): 2484–90. http://dx.doi.org/10.24297/jac.v10i3.6655.

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The mixed compound NaH2(PO4)0.48(AsO4)0.52.H2O, which has been examined by Raman spectroscopy, XRD powder and dielectric, exhibits solid–solid phase transitions and one reversible solid–liquid phase transition. Besides, the investigation of dehydration behavior of sodium dihydrogenate phosphate-arsenate monohydrate was undertaken in a temperature range from 253 K to 333 K. The onset temperature of dehydration was determined from changes in ionic conductivity and X-ray powder on heating. It was confirmed by the Raman study not only in the disappearance of the vibrations assigned to the PO4, AsO4 but also in the appearance of the new vibrations attributed to the (PO3), which constitutes the P-O-P chain, giving a polymer with the formula: NaH2(P2O7)x(As2O7)(1-x). The important variation was observed in all studies at 313 K, which could correspond to the transformation of the NDAP compounds of a solid crystal into a liquid form.

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40

Bento da Silva, Juarez, Luan da Silva Frasseto, Leticia Rocha Machado, Simone Meister Sommer Bilessimo, and Isabela Nardi da Silva. "A Pedagogical Model for Integrating Digital Technologies in Education: Workshops on Sustainable Development Goals (SDGS)." Journal of Information Technology Education: Research 22 (2023): 461–79. http://dx.doi.org/10.28945/5219.

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Aim/Purpose: A proposal for a pedagogical model that integrates digital technologies in teaching Sustainable Development Goals (SDGs) in K-12 Education. Background: The research is developed within project InTecEdu (Integration of Technology in Education), developed by the research group since 2008, and focusing on social inclusion for highly socially vulnerable K-12 students. Methodology: The research was exploratory and qualitative; data was collected through a questionnaire and participant observation, with 253 students and 9 teachers from 5 Brazilian public schools. Contribution: The research contributes by bringing a pedagogical model for integrating SDGs and Information and Communication Technologies (ICTs) in K-12 education. Findings: All analyzed aspects received a high level of approval, although some opportunities for improvement were identified, such as the duration and frequency of the session. Recommendation for Researchers: We recommend the reuse of the pedagogical model, since our intention is for it to be open-source, and free to use. Impact on Society: The paper is aligned with the fourth SDG: Quality Education. It directly contributes with the education of 253 socially vulnerable students from a south American public school, and indirectly contributes with improvement of education. Future Research: To improve the pedagogical model based on the feedback from the questionnaires and apply it with a more extensive scenario.

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41

Lusser, Maria, and Paul Peringer. "Synthese, Charakterisierung und Dynamik von [Hg(η1-dppm)3](O3SCF3)2, dppm = Bis(diphenylphosphino)methan / Synthesis, Characterisation and Fluxionality of [Hg(η1-dppm)3](O3SCF3)2, dppm = Bis(diphenylphosphino)methane." Zeitschrift für Naturforschung B 40, no. 10 (October 1, 1985): 1417–18. http://dx.doi.org/10.1515/znb-1985-1030.

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The title compound is formed from [Hg(η1-dppm)2](O3SCF3)2 and dppm, and is fluxional on the NMR time scale as the result of fast intramolecular displacement of coordinated phosphorus by free phosphorus in the η1-dppm ligands; at temperatures above 253 K intermolecular ligand exchange sets in.

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Qin, Qin, Tingwei Sun, Hanxiao Wang, Pascal Brault, Haojie An, Lu Xie, and Qing Peng. "Adsorption and Diffusion of Hydrogen in Carbon Honeycomb." Nanomaterials 10, no. 2 (February 18, 2020): 344. http://dx.doi.org/10.3390/nano10020344.

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Carbon honeycomb has a nanoporous structure with good mechanical properties including strength. Here we investigate the adsorption and diffusion of hydrogen in carbon honeycomb via grand canonical Monte Carlo simulations and molecular dynamics simulations including strength. Based on the adsorption simulations, molecular dynamics simulations are employed to study the effect of pressure and temperature for the adsorption and diffusion of hydrogen. To study the effect of pressure, we select the 0.1, 1, 5, 10, 15, and 20 bars. Meanwhile, we have studied the hydrogen storage capacities of the carbon honeycomb at 77 K, 153 K, 193 K, 253 K and 298 K. A high hydrogen adsorption of 4.36 wt.% is achieved at 77 K and 20 bars. The excellent mechanical properties of carbon honeycomb and its unique three-dimensional honeycomb microporous structure provide a strong guarantee for its application in practical engineering fields.

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43

Barret, Cécile, Christian Roy, Philippe Montcourrier, Paul Mangeat, and Verena Niggli. "Mutagenesis of the Phosphatidylinositol 4,5-Bisphosphate (Pip2) Binding Site in the Nh2-Terminal Domain of Ezrin Correlates with Its Altered Cellular Distribution." Journal of Cell Biology 151, no. 5 (November 27, 2000): 1067–80. http://dx.doi.org/10.1083/jcb.151.5.1067.

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The cytoskeleton-membrane linker protein ezrin has been shown to associate with phosphatidyl-inositol 4,5-bisphosphate (PIP2)-containing liposomes via its NH2-terminal domain. Using internal deletions and COOH-terminal truncations, determinants of PIP2 binding were located to amino acids 12–115 and 233–310. Both regions contain a KK(X)nK/RK motif conserved in the ezrin/radixin/moesin family. K/N mutations of residues 253 and 254 or 262 and 263 did not affect cosedimentation of ezrin 1-333 with PIP2-containing liposomes, but their combination almost completely abolished the capacity for interaction. Similarly, double mutation of Lys 63, 64 to Asn only partially reduced lipid interaction, but combined with the double mutation K253N, K254N, the interaction of PIP2 with ezrin 1-333 was strongly inhibited. Similar data were obtained with full-length ezrin. When residues 253, 254, 262, and 263 were mutated in full-length ezrin, the in vitro interaction with the cytoplasmic tail of CD44 was not impaired but was no longer PIP2 dependent. This construct was also expressed in COS1 and A431 cells. Unlike wild-type ezrin, it was not any more localized to dorsal actin-rich structures, but redistributed to the cytoplasm without strongly affecting the actin-rich structures. We have thus identified determinants of the PIP2 binding site in ezrin whose mutagenesis correlates with an altered cellular localization.

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44

Sinha, N. K., C. Zhan, and E. Evgin. "Uniaxial Constant Compressive Stress Creep Tests on Sea Ice." Journal of Offshore Mechanics and Arctic Engineering 117, no. 4 (November 1, 1995): 283–89. http://dx.doi.org/10.1115/1.2827235.

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First-year columnar-grained sea ice from Resolute Passage (74° 42′ N, 94° 50′ W), off Barrow Strait in the Canadian High Arctic, was tested under constant uniaxial compressive stress applied normal to the length of the columns. Creep tests were performed at 263 K, 253 K, and 243 K in the stress range of 0.7 to 2.5 MPa, using prismatic samples with dimensions of 50 mm × 100 mm × 250 mm. Because three-dimensional creep data are extremely useful for developing constitutive equations, axial strain was measured in conjunction with the measurements of two lateral strains and acoustic emissions. The deformations were measured using displacement gages mounted on the samples. A description of the experimental procedures and the observations are presented here. One-to-one correspondence has been obtained between the present results on the dependence of minimum creep rate on stress and previous data on the dependence of uniaxial compressive strength on strain rate under constant strain rate. The strain-rate sensitivity of compressive strength can, therefore, be obtained from creep tests which can be performed by using simple dead-load test systems.

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45

Chen, L., T. Uchimaru, S. Kutsuna, K. Tokuhashi, and A. Sekiya. "Kinetics of the gas-phase reactions of CHXCFX (X = H, F) with OH (253-328 K) and NO3 (298 K) radicals and O3 (236-308 K)." International Journal of Chemical Kinetics 42, no. 10 (July 16, 2010): 619–28. http://dx.doi.org/10.1002/kin.20506.

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46

Thanh Nien Le. "Phân Tích Nhiệt Động Của Một Số Loại Môi Chất Lạnh Dùng Trong Tủ Lạnh Và Kho Lạnh Công Nghiệp." Journal of Technical Education Science 19, SI01 (February 28, 2024): 20–28. http://dx.doi.org/10.54644/jte.2024.1252.

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Phân tích exergy là công cụ mạnh mẽ trong thiết kế, tối ưu hóa và đánh giá hiệu suất của hệ thống năng lượng. Trong bài báo này, tác giả phân tích nhiệt động của các hệ thống lạnh một cấp nén môi chất R22, R717, R404A, R507A, R1234yf, R134a, R600a bằng các thông số: Nhiệt độ đầu đẩy máy nén T2 [K], năng suất lạnh riêng thể tích qv [kJ/m3] , hệ số làm lạnh COP, hiệu suất exergy COPex, độ hoàn thiện chu trình η[%], tổn thất exergy Exd,total [kW] tại nhiệt độ ngưng tụ Tk = 315[K], nhiệt độ bay hơi T0 = 268[K], 265[K], 258[K], 253[K], 248[K], 243[K], 238[K]. Qua đó, tác giả nhận thấy rằng trong các hệ thống lạnh nhiệt độ âm có công suất nhỏ như tủ lạnh, tủ kem thì môi chất R600a vì cho kết quả hệ số làm lạnh COP, hiệu suất exergy, năng suất lạnh thể tích riêng, độ hoàn thiện chu trình lớn hơn R134a và cao nhất trong các loại môi chất lạnh được sự dụng hiện nay. Trong các hệ thống kho lạnh công nghiệp thì môi chất R22 có nhiệt độ cuối tầm nén thấp hơn NH3 dẫn đến có thể không bắt buộc có thêm hệ thống làm mát đầu đẩy máy nén, hệ số làm lạnh COP gần giống nhau, tổn thất exergy NH3 quá lớn dù hiệu suất exergy gần giống nhau. Nếu xét về mặt ảnh hưởng tới môi trường thì môi chất lạnh NH3 vẫn là ưu tiên lựa chọn so với R22.

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47

Boose, Yvonne, André Welti, James Atkinson, Fabiola Ramelli, Anja Danielczok, Heinz G. Bingemer, Michael Plötze, Berko Sierau, Zamin A. Kanji, and Ulrike Lohmann. "Heterogeneous ice nucleation on dust particles sourced from nine deserts worldwide – Part 1: Immersion freezing." Atmospheric Chemistry and Physics 16, no. 23 (December 6, 2016): 15075–95. http://dx.doi.org/10.5194/acp-16-15075-2016.

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Abstract. Desert dust is one of the most abundant ice nucleating particle types in the atmosphere. Traditionally, clay minerals were assumed to determine the ice nucleation ability of desert dust and constituted the focus of ice nucleation studies over several decades. Recently some feldspar species were identified to be ice active at much higher temperatures than clay minerals, redirecting studies to investigate the contribution of feldspar to ice nucleation on desert dust. However, so far no study has shown the atmospheric relevance of this mineral phase.For this study four dust samples were collected after airborne transport in the troposphere from the Sahara to different locations (Crete, the Peloponnese, Canary Islands, and the Sinai Peninsula). Additionally, 11 dust samples were collected from the surface from nine of the biggest deserts worldwide. The samples were used to study the ice nucleation behavior specific to different desert dusts. Furthermore, we investigated how representative surface-collected dust is for the atmosphere by comparing to the ice nucleation activity of the airborne samples. We used the IMCA-ZINC setup to form droplets on single aerosol particles which were subsequently exposed to temperatures between 233 and 250 K. Dust particles were collected in parallel on filters for offline cold-stage ice nucleation experiments at 253–263 K. To help the interpretation of the ice nucleation experiments the mineralogical composition of the dusts was investigated. We find that a higher ice nucleation activity in a given sample at 253 K can be attributed to the K-feldspar content present in this sample, whereas at temperatures between 238 and 245 K it is attributed to the sum of feldspar and quartz content present. A high clay content, in contrast, is associated with lower ice nucleation activity. This confirms the importance of feldspar above 250 K and the role of quartz and feldspars determining the ice nucleation activities at lower temperatures as found by earlier studies for monomineral dusts. The airborne samples show on average a lower ice nucleation activity than the surface-collected ones. Furthermore, we find that under certain conditions milling can lead to a decrease in the ice nucleation ability of polymineral samples due to the different hardness and cleavage of individual mineral phases causing an increase of minerals with low ice nucleation ability in the atmospherically relevant size fraction. Comparison of our data set to an existing desert dust parameterization confirms its applicability for climate models. Our results suggest that for an improved prediction of the ice nucleation ability of desert dust in the atmosphere, the modeling of emission and atmospheric transport of the feldspar and quartz mineral phases would be key, while other minerals are only of minor importance.

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Wertz, David L., and Andrew J. Holder. "Conformational study of liquid-state 1,3-dichloropropane at 253 K using wide-angle x-ray scattering." Journal of Physical Chemistry 91, no. 13 (June 1987): 3479–82. http://dx.doi.org/10.1021/j100297a005.

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49

Lin, Hong, and Yuan-Yuan Duan. "Surface Tension Measurements of Propane (R-290) and Isobutane (R-600a) from (253 to 333) K." Journal of Chemical & Engineering Data 48, no. 5 (September 2003): 1360–63. http://dx.doi.org/10.1021/je034093m.

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50

Gierczak, T., B. Rajakumar, Jonathan E. Flad, and James B. Burkholder. "Rate coefficients for the reaction of the acetyl radical, CH3CO, with Cl2between 253 and 384 K." International Journal of Chemical Kinetics 41, no. 8 (August 2009): 543–53. http://dx.doi.org/10.1002/kin.20430.

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