Subjects: Statistics >> Social Statistics submitted time 2024-03-27 Cooperative journals: 《中国科学院院刊》
Abstract： “To set an example of green development and strength ecological environmental protection in the Chishui River basin” is an important proposal listed in the Outline of the 14th Five-Year Plan (2021--2025) for National Economic and Social Development and Vision 2035 of the People’s Republic of China. Strengthening eco-environmental protection in the Chishui River will play an exemplary and leading role in maintaining fish diversity of the upper Yangtze River, promoting regional high-quality development, and creating a new situation of ecological civilization and Beautiful China. This study interprets the ecological functions of the Chishui River in the upper Yangtze River, expounds the effectiveness of ecological protection and restoration in recent years, and proposes measures and suggestions to strengthen the ecological protection and restoration from the perspective of whole basin protection and ecosystem restoration.
Subjects: Library Science，Information Science >> Library Science submitted time 2023-11-06
Abstract： The evaluation of discipline construction effect is so important to the strategy formulation, program implementation and development path of discipline construction. ESI data can be used as one of the dynamic monitoring data to objectively evaluate the effectiveness of university discipline construction. The paper constructs an objective evaluation model of discipline construction effectiveness based on ESI highly cited papers. Taking H University as a case, the paper analyzes the tracking data of 30 ESI highly cited papers of H University in the past five years through bibliometrics and statistics methods. It finds that H University has achieved remarkable results in discipline construction, with teachers, students, faculties and departments making efforts. Dominant disciplines’ construction is outstanding, but some disciplines’ construction is slow. In the future, the university can adjust development path from the system mechanism, professional layout, team construction, etc., and promote more disciplines to become world-class disciplines.
Peer Review Status:
Awaiting Review
Subjects: Library Science，Information Science >> Information Science submitted time 2023-09-21
Abstract： Purpose/significance By using the uniqueness and linkability of linked data, the paper tries to discover and correlate academic relationship of institutional repository entities，in order to realize institutional repository resources semantic aggregating. Method/process It analyzes the types and characteristics of the entity academic relationship and linked data requirements, then puts forward academic relationship association methods. Finally it uses the data of Hohai University Institutional Repository to conduct an empirical study. Results/Conclusion The paper builds the method of discovering entity academic relationships based on linked data. It finds out the academic relationships of empirical data and points out its application value. This method can realize semantic associating of institutional repository resources, and provide knowledge retrieval service based on linked data, which can meet user's knowledge needs.
Subjects: Other Disciplines >> Synthetic discipline submitted time 2023-03-28 Cooperative journals: 《中国科学院院刊》
Abstract： The red soil hilly areas in South China were prone to soil erosion due to their poor soil viscosity, poor water permeability, and inadequate seasonal rainfall distribution. Inappropriate tillage measures aggravated soil erosion, decreased soil fertility, and therefore restricted the sustainable development of local agriculture. Since the Taoyuan Agro-ecosystem Research Station, Chinese Academy of Sciences (CAS) was established in 1979, researchers have systematically upgraded management of regional agricultural ecosystem, increased the overall agricultural benefits, and established a technical system and an optimized mode of the comprehensive development of regional agriculture in the station. The demonstration and promotion will provide important theoretical and technical support for soil erosion control, regional agricultural restructuring, and the improvement of farmland productivity and ecological environment in red soil hilly areas in South China. We have systematically studied the formation mechanism of gley and secondary gley paddy soil to provide technical support for gleyed paddy field management; the coordination mechanism between sustainable productivity and system health of paddy field ecosystem to provide theoretical basis and technical support for sustainable and efficient production of paddy field ecosystem in red soil; the microbial mechanism driving the key processes of N2O and CH4 emission from rice fields to provide vital scientific basis for reducing greenhouse gas emission in farmland of China; the distribution pattern and the main driving factors of soil bacteria and denitrifying microorganism in farmland to depict the composition of farmland soil microbial community in the large scale; the control mechanism of functional amino acid metabolism and physiological function of pig diet to scientifically improve the level of pig breeding and the development of China’s pig breeding industry in a healthy and sustainable way; nitrogen transformation mechanism in vegetable soil and the corresponding control measures to provide a strong theoretical foundation and technical support for nitrogen control in vegetable soil; the characteristics and influencing factors of nutrient loss in typical farmland ecosystem, the model of nitrogen and phosphorus interception and ecological absorption in hilly composite agricultural ecosystem to provide technical support for the prevention and control of non-point source pollution of nitrogen and phosphorus in farmland ecosystems; recycling utilization model of agricultural and pastoral resources to promote the sustainable development of local agriculture. In the future, the scientists of Taoyuan Agro-ecosystem Research Station will make greater contribution to the sustainable development of regional agriculture under the guidance of the “Pioneer Initiative Action ” plan of CAS.
Subjects: Materials Science >> Materials Science (General) submitted time 2023-03-19 Cooperative journals: 《金属学报》
Abstract： Ceramic matrix composites (CMCs) is attracted in airspace and nuclear engineering due to their high temperature, corrosion and wearing resistance, but the usage is limited by the joining between CMC and other metals due to obvious incompatibility on physical and chemical aspects on them. The liquid phase-diffusion bonding (LPDB) on Ti(C, N)-Al2O3 CMC/Cu joint was studied using the Cu-Zr foil/Cu foil/Cu-Zr foil sanwich as an interlayer in this work. Auxiliary pulse current was also added to control the elemental diffusion and interfacial reaction during LPDB. The element diffusion and reacted products at the interface were analyzed with SEM, EPMA and EDS, and the joint strength was tested with four points bending method. The results show that with an auxiliary pulse current during LPDB, a higher joint strength is reached with a lower bonding temperature and a shorter holding time. The diffusion behavior of element Zr and Cu in CMC and the interfacial area is obviously changed, and the activity of Zr element and its chemical reaction with Al2O3 are depressed by the auxiliary pulse current during LPDB. The diffusion of ceramic partilces into the interface and the thickness of corresponding diffusion transition zone (DTZ) and Zr-Cu interfacial reaction zone (IRZ) at the interface are also depressed by the auxiliary pulse current, which strengthens the interface, and is always kept an higher joint strength.
Subjects: Biology >> Bioengineering submitted time 2017-11-21 Cooperative journals: 《中国生物工程杂志》
Abstract：低温CPC乙酰化酶在7-ACA的生物合成中具有重要作用和显著的优势，开发低温CPC乙酰化酶具有重大的经济价值。为了获得在低温下具有更高催化活性的CPC乙酰化酶，本文在前期的研究基础上，以先前获得的CA IIIM为亲本，借助分子对接的手段确定了它的底物结合区域，并利用pyMOL软件找出了底物结合区域Loop上关键的脯氨酸残基，分析后将选定的脯氨酸用甘氨酸进行替换。借助pET32a质粒在E. coli BL21(DE3)中进行了可溶性表达研究，除P272G外，其它突变体均实现了可溶性表达。P238G、P582G和P679G在13℃对CPC的催化活性分别为1.25、1.04和1.38 U/mg，较亲本的0.85 U/mg有了显著的提高。此外，分别考察了亲本及突变体的温度稳定性，它们之间无明显的差异。然后，在13℃下进行了7-ACA低温生物合成的研究，结果表明反应24 h后CPC的转化率也能达到80%以上。本研究在CPC乙酰化酶冷适应性改造方面取得了较为理想的结果，为进一步的改造及应用奠定了坚实的基础，也为其它低温酶的创制提供了可资借鉴的经验。
Subjects: Biology >> Bioengineering submitted time 2017-11-21 Cooperative journals: 《中国生物工程杂志》
Abstract：低温CPC乙酰化酶在7-ACA的生物合成中具有重要作用和显著的优势，开发低温CPC乙酰化酶具有重大的经济价值。为了获得在低温下具有更高催化活性的CPC乙酰化酶，本文在前期的研究基础上，以先前获得的CA IIIM为亲本，借助分子对接的手段确定了它的底物结合区域，并利用pyMOL软件找出了底物结合区域Loop上关键的脯氨酸残基，分析后将选定的脯氨酸用甘氨酸进行替换。借助pET32a质粒在E. coli BL21(DE3)中进行了可溶性表达研究，除P272G外，其它突变体均实现了可溶性表达。P238G、P582G和P679G在13℃对CPC的催化活性分别为1.25、1.04和1.38 U/mg，较亲本的0.85 U/mg有了显著的提高。此外，分别考察了亲本及突变体的温度稳定性，它们之间无明显的差异。然后，在13℃下进行了7-ACA低温生物合成的研究，结果表明反应24 h后CPC的转化率也能达到80%以上。本研究在CPC乙酰化酶冷适应性改造方面取得了较为理想的结果，为进一步的改造及应用奠定了坚实的基础，也为其它低温酶的创制提供了可资借鉴的经验。
Subjects: Dynamic and Electric Engineering >> Engineering Thermophysics submitted time 2017-11-07 Cooperative journals: 《工程热物理学报》
Abstract： In this paper, the formation of micelle, velocity distribution, and rheological behavior in surfactant aqueous solution under couette flow were studied using coarse-grained molecular dynamics simulations. Simulation results show that the dynamic equilibration time becomes shorter with the increase of shear rate on the condition of the same surfactant aqueous solution concentration. If the shear rate is a constant number, the formation of a micelle was more rapid when the surfactant molecular concentration increases in the aqueous solution. When the surfactant molecular concentration keeps constant, the shear viscosity becomes smaller with the increase of shear rate, and the shear-thinning characteristic can be obtained.
Subjects: Astronomy >> Astrophysical processes submitted time 2017-10-20 Cooperative journals: 《天文研究与技术》
Abstract：介绍了明安图射电频谱日像仪高频阵模拟接收机总体设计方案和研制情况，详细说明所采用的光传输、温控、滤波、LTCC等技术以及针对射电日像仪阵列特别采取的可靠性保证措施。经过全面的系统指标测试和幅、相稳定性温度环境测试，结果表明模拟接收机系统的性能、功能和稳定性等指标满足总系统的设计要求。
Hits
Hits
Downloads
Comment
YES