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Copyright of Journal of Chinese Institute of Food Science & Technology is the property of Journal of Chinese Institute of Food Science & Technology Periodical Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Refrigeration is the property of Journal of Refrigeration Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Industrial Water Treatment is the property of CNOOC Tianjin Chemical Research & Design Institute and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of China Medical University is the property of Journal of China Medical University Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of China Medical University is the property of Journal of China Medical University Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Bulletin of Soil & Water Conservation is the property of Bulletin of Soil & Water Conservation Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

More cost-saving and efficient freezing is required to enhance the performance of quick freezing for blueberries. In this study, a new system was proposed to utilize a multi-outlet array nozzle for spraying blueberries with dry ice particles. Experimental tests were conducted to investigate the variations in the thermal properties of blueberries with temperature during the freezing process. These parameters were then input into Fluent software. A quick-freezing model was established for the dry ice particle spray inside the chamber. Numerical simulation was conducted to simulate the blueberry quick freezing using Fluent software. The optimal inlet flow velocity was successfully obtained to optimize the nozzle outlet diameter after the simulation. The results indicate that the better precooling of blueberries in cold water was to a temperature of 1℃. The nozzle was designed with six outlets in a circular array, where the central lines of the outlets were inclined at a 60° angle from the central line of the nozzle inlet, while the aperture size was 5.2 mm, and the nozzle was designed in a circular aperture shape with a contraction form. Additionally, four outlets were arranged at the center position of the nozzle's entrance axis, each with a diameter of 2 mm. The nozzle was configured with a spraying height of 120 mm, an entrance aperture measuring 30 mm, and an inlet velocity of 0.25 m/s. The center temperature of all the blueberries decreased from 1℃ to −18℃ in a total of 129 s, indicating the more uniform and quick freezing of the blueberries. Experimental testing was conducted to validate the simulation. An optimal combination was achieved in the freezing process of 127 s at the slowest cooling rate, with a time of 36 s for the formation of the maximum ice crystal generation zone. The cooling curves of the experimental process and the simulation process match well. The thawed blueberries were then subjected to physicochemical property testing after three days of storage. The results show that the blueberries subjected to quick freezing using dry ice particle spraying exhibited superior changes in their quality before and after freezing, compared with the CXS 103-1981 standard for frozen blueberries. A comparative experiment show that the blueberries were subsequently subjected to quick freezing using direct spraying of liquid nitrogen at −80℃. However, the dry ice cost much less for the quick freezing of blueberries, compared with the direct spraying with −80℃ liquid nitrogen. This low cost further enhanced the feasibility and economic viability of dry ice for blueberry freezing. The physicochemical property tests showed that there was almost no difference with the dry ice. The research findings can provide a solid foundation for the widespread application of the quick freezing of blueberries using dry ice spray. [ABSTRACT FROM AUTHOR]

Copyright of Arid Land Geography is the property of Chinese Academy of Sciences, Xinjiang Institute of Ecology & Geography and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Engineering Management & Technology Discussion is the property of Omniscient Pte. Ltd. and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Chinese Institute of Food Science & Technology is the property of Journal of Chinese Institute of Food Science & Technology Periodical Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

With the widespread application of gallium nitride (GaN) in the high-power field, the heat dissipation of GaN based devices has become the main factor restricting the power density. Therefore, it is crucial to develop novel thermal management solutions. Diamond substrates with high thermal conductivity can be used to improve the heat dissipation of GaN devices. However, due to the natural lattice mismatch between diamond and GaN, the direct epitaxy of GaN on diamond substrates remains an insurmountable problem. This work achieved van der Waals epitaxy of single crystal GaN films on polycrystalline diamond substrates using a two-dimensional material / Al gradient AlGaN heterostructure as the nucleation layer between the substrate and the epitaxial layer. Among them, two-dimensional materials can effectively shield against the adverse effects caused by lattice mismatch between the substrate and epitaxial layer, while the Al component gradient AlGaN buffer layer can achieve orderly migration of Ga and N atoms, thereby accurately controlling the growth of GaN thin films. This work provides a novel approach for high-quality growth of nitrides on heterogeneous substrates. The experimental results indicate that the introduction of nucleation layers effectively eliminates the impact of lattice mismatch, thereby breaking the bottleneck of the difficulty in directly epitaxial single crystal GaN films on diamond substrates. This work provides a foundation for further improving the power density of GaN based devices. [ABSTRACT FROM AUTHOR]

Copyright of Transactions of the Chinese Society of Agricultural Engineering is the property of Chinese Society of Agricultural Engineering and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Modern Laboratory Medicine is the property of Journal of Modern Laboratory Medicine Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Educational Studies (1673-1298) is the property of Journal of Educational Studies Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

目的 基于单细胞分化轨迹筛选胶质母细胞瘤 (GBM) 细胞分化相关基因 (DRG), 构建预后模型并加以 验证。方法 通过基因表达综合数据库中18例GBM样本的单细胞测序数据分析细胞分化轨迹, 筛选DRG, 并进行 富集分析; 结合癌症基因组图谱数据库中169例GBM患者的生存时间和生存状态, 用单因素Cox回归分析和多因素 Cox回归分析对DRG进行筛选并建立预后模型和动态列线图; 对模型进行验证和内部特征分析。结果 GBM细胞 分化轨迹中存在7种不同状态的细胞亚群, 在细胞发育初期, 主要的细胞为间充质干细胞 (MSC), 中期部分MSC停 止分化, 部分 MSC分化为神经元细胞 (Neurons), 晚期主要存在星形胶质细胞 (Astrosyte) 和部分 Neurons细胞。对 7 组不同状态的细胞进行组间差异分析后共获得了518个DRG, 京都基因与基因组百科全书 (KEGG) 富集分析结果显 示, DRG主要富集在局部粘连, 冠状病毒感染-COVID-19, p53信号传导途径, 核糖体, 细胞衰老, ECM与受体的相互 作用等信号通路; 基因本体富集结果显示, DRG主要富集在伤口愈合, 轴突发育, 细胞外基质, 含胶原蛋白, 焦点黏 附, 结构成分等; 疾病本体富集分析结果显示, DRG与周围神经系统, 自主神经系统, 恶性胶质瘤, 神经母细胞瘤, 星 形细胞瘤, 多形性GBM密切相关。用4个DRG (SPP1, IFI44L, CD81, AEBP1) 建立预后模型, 经过验证该预后模型具 有良好的准确性。根据风险分数的中位值将所有患者分为高风险组和低风险组, 与低风险组相比, 高风险组的总生 存期短, 高风险组和低风险组在免疫微环境中存在着大量差异。根据DRG的表达值和患者临床特征建立的动态列 线图具有极强的预测性能和临床实用性。结论 GBM细胞的复杂分化过程影响患者预后, DRG相关的预后模型和 动态列线图可以准确预测GBM患者的预后. [ABSTRACT FROM AUTHOR]

Copyright of Telecommunication Engineering is the property of Telecommunication Engineering and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Urban Architecture & Development is the property of Omniscient Pte. Ltd. and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Hydrobiology is the property of Editorial Department of Journal of Hydrobiology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Because the karst critical zone is an important part of the Earth Critical Zone system, the vegetation in karst area is an important carbon sink of terrestrial ecosystem, and the aboveground part of the vegetation in the karst area sequestrates carbon through plant growth, the carbon storage in the underground part is also very considerable, the growth of underground biomass and decomposition of litter also increase soil organic carbon and inorganic carbon content. Therefore, vegetation carbon cycle in karst area is one of the hotspots of karst carbon sink research. Based on the reviewing of research literature on carbon sequestration of karst vegetation in the past 40 years, this paper expounds the unique physiological characteristics of karst vegetation in Southwest China, and focuses on the following four aspects; (1) Evaluation of vegetation biomass, productivity and carbon storage in karst area of Southwest China; (2) Temporal and spatial variation patterns of vegetation and carbon source and sink effect in karst area of Southwest China; (3) Special mechanism of vegetation carbon utilization in karst area; (4) Prediction of vegetation carbon cycle model and carbon sink potential in karst area. The problems existing in the current research am put forward, and the future research direction is prospected. It is proposed that the future research should be carried out in the aspects of systematic determination of relevant parameters and mechanism process of vegetation carbon cycle in karst area, fine identification of vegetation landscape types in southwest karst area, quantification of carbon sequestration process, and correction and modification of karst vegetation carbon cycle model. This paper provides a reference for in-depth understanding the temporal and spatial evolution of carbon cycle in karst region and for exploring regional carbon cycle mechanism. [ABSTRACT FROM AUTHOR]

Copyright of Water Conservancy Science & Techonlogy & Economy is the property of Water Conservancy Science & Technology & Economy Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Shipin Kexue/ Food Science is the property of Food Science Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Food & Machinery is the property of Food & Machinery Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Engineering for Thermal Energy & Power / Reneng Dongli Gongcheng is the property of Journal of Engineering for Thermal Energy & Power and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Objective To explore the impact of home restriction on preschool children′s activity behavior during the epidemic period,so as to provide basis for guiding children′s healthy life in special periods.Methods 1 453 preschool children with home restrictions in 7 kindergartens in Guangzhou from March 9 to12,2020 were selected by cluster random method.A self-made questionnaire was used to investigate their sleep status,exercise status,sedentary behavior and other activities during normal times and epidemic periods.At the same time,the respondents were divided into groups according to gender,age,only child or not,the main caregivers and their educational level,and the changes of activity behavior indicators in each group were compared.Results A total of 1 453 questionnaires were distributed and 1 449 valid questionnaires were recovered.The recovery rate of valid questionnaires was 99.72%.There were significant differences in the time of falling asleep,wake-up time,sleep time,daily exercise time,weekly exercise time,total daily sedentary time,Non screen sedentary time and screen sedentary time between normal times and the epidemic period（P<0.05）.There were significant differences in the changes range of wake-up time,daily exercise time and daily sedentary time in children of the care groups with different educational levels during the epidemic period（P<0.05）;there were no significant differences in the changes range of falling asleep time,night sleep time and weekly exercise time（P>0.05）.There were no significant differences in the change range of activity behavior indexes in other groups（P<0.05）.Conclusion During the epidemic period,the sleep,exercise and sedentary behaviors of preschool children limited by home have changed compared with normal times.The education level of the main caregivers may affect the children′s wake-up time,exercise time and sedentary behavior during the epidemic period.Therefore,we should pay attention to the management of preschool children′s activity behavior. [ABSTRACT FROM AUTHOR]

Copyright of Chinese Medical Equipment Journal is the property of Chinese Medical Equipment Journal Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Precious Metals / Guijinshu is the property of Precious Metals Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Study on Optical Communications / Guangtongxin Yanjiu is the property of Study on Optical Communications Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Quick-frozen fruits and vegetables have a high demand on the processing device for rapid freezing, due to the ever-increasing requirements for the high quality and nutritional value to taste of consumers in food production. The purpose of this study is to use the sublimation process of dry ice particles, further to form the superfast freezing in low temperature environment, in order to adequately keep the original color, flavor, and high quality nutrition of frozen products, while, shorten the freezing time and improve the freezing efficiency. Taking the strawberry as the research material, natural dry ice particles were sprayed into a quick-freezing room, concurrently skimmed quickly the surface of strawberry, and fully contacted with the strawberry to exchange the heat. Therefore, a new innovated platform was designed, including the fabrication of dry ice pellet, spraying system, a quick-freezing room, and a feasible pallet. A thermomechanical model of strawberry in the quick-freezing room was established, to simulate the distribution of temperature, velocity, and pressure during the dry ice spraying using the Comsol multiphysics software. The inlet radius of dry ice jet was set under the conditions of 18, 20, 23, 25 and 30 mm, and the injection velocity was set as 0.10, 0.15, 0.20, 0.25, 0.30, 0.40, 0.50 m/s, thereby to determine the time when the core temperature and surface temperature of strawberry met the requirements of quick freezing. The solid fraction of dry ice in different time was compared, when the injection velocities of dry ice were 0.20 and 0.30 m/s. The results showed that the freezing time of strawberry decreased, while the freezing efficiency increased, with the increase of the inlet radius and the spray speed of dry ice. When the inlet radius was 25 mm and the flow velocity was 0.30 m/s, the core temperature of all strawberries reached -18℃ at 350s, indicating the uniform distribution of temperature, and the shortest duration between the strawberry surface to -35 ℃ and the strawberry core to -18 ℃. In this case, it was expected to effectively prevent the surface cracking caused by the excessive difference of internal and external temperature in a strawberry. Meanwhile, the solid fraction of exported dry ice was less than others, indicating the quick freezing of strawberry realized with the maximum efficiency. Compared with liquid nitrogen spraying, the zone of the maximum ice crystal formation and the freezing time of dry frozen strawberry reduced by 63.9% and 41.7%, respectively, indicating the excellent cooling performance using dry ice spray. In addition, the quick-frozen quality of strawberry was significantly improved, due to the less freezing time, the improved freezing efficiency, and the reduced energy consumption of system operation, meanwhile, to better preserve the strawberry juice, original color, flavor, and nutrition. An experiment was also used to verify the optimal parameters, where the experimental and simulation errors were 3.70% and 6.03%, respectively, when the surface temperature and core temperature reached the standard value. Specifically, the physical and chemical properties of strawberries were better than the standard after quick-freezing. The finding can lay a sound foundation for further development of energy-saving and environment-friendly dry frozen devices for fruits and vegetables. [ABSTRACT FROM AUTHOR]

Copyright of Telecommunication Engineering is the property of Telecommunication Engineering and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)