Subjects: Other Disciplines >> Synthetic discipline submitted time 2023-03-28 Cooperative journals: 《中国科学院院刊》
Abstract： Underwater acoustic detection technology is the most important research direction on underwater acoustic signal processing and sonar filed, and is the key technology on marine applications for environment aware, ocean surveillance, resource exploration, information acquisition and so on. This paper gives a brief introduction on the current status of underwater acoustic detection. With scientific problems in practice, the new concept, new method, and new trend of this field are presented. Subsequently, the important effect of underwater acoustic detection development on national security and economic progress is analyzed and prospected.
Subjects: Statistics >> Social Statistics submitted time 2024-05-18 Cooperative journals: 《中国科学院院刊》
Abstract： Urbanized areas are areas whose main function is to provide industrial and service products. During the 15th Five-Year Plan period, the urbanization rate of China’s population will exceed 70 percent, thus entering a long-time stage of high urbanization levels. The strategic positioning of urbanized areas will be defined as county-level administrative districts with a high concentration of scientific and technological innovation resources, new quality productivity, and new-type industrialization. In terms of strategic layout, the scope of urbanized areas will be optimized to promote the concentration of population and economy in urban agglomerations, metropolitan areas, and central cities, and to strengthen the suburbanization of mega cities, as well as the integrated development of urban and rural areas. In terms of functional upgrading, it will promote the layout of new quality productivity and new industrialization in different urbanized areas according to their comparative advantages, and strengthen the leading role of Beijing-Tianjin-Hebei, the Yangtze River Delta, the Pearl River Delta, and Chengdu-Chongqing area. In terms of spatial quality, it is necessary to promote the livability, intelligence, and resilience of cities.
Subjects: Astronomy >> Astrophysical processes submitted time 2021-07-06 Cooperative journals: 《天文研究与技术》
Abstract：利用美国甚长基线干涉阵，对致密射电源0223+341和0248+430进行了4.6GHz的偏振观测，获得了角分辨率高达2毫角秒的辐射强度分布图像，并首次得到了这两个射电源在4.6GHz频率的偏振矢量分布结果。其中致密陡谱源0223+341未观测到射电核，射电结构主要由两个疑似热斑的成份组成，偏振辐射集中在其中一个热斑处，而偏振度较低，周围可能有较浓密的介质；而吉赫兹反转谱源0248+430呈现单侧核—喷流结构，偏振辐射集中在射电核附近。
Subjects: Geosciences >> Space Physics submitted time 2017-03-10
Abstract：基于多项式校正方法，建立了针对图像坐标的公式模型，利用MATLAB中的曲面拟合工具（Surface Fitting Tool）得到了多项式参数，实现了对紫外探测器成像畸变的校正。本文介绍了楔条形阳极紫外探测器的畸变产生原因以及多项式校正的原理，设计了一个应用于LabVIEW的dll模块，通过小孔掩模板实验求得多项式并应用于分辨率板的成像，实现了对分辨率板成像的畸变校正。
Peer Review Status:
Awaiting Review
Subjects: Materials Science >> Materials Science (General) submitted time 2023-03-19 Cooperative journals: 《金属学报》
Abstract： New Ni-free Zr61.5Cu21.5-xFe5Al11Sn1Nbx (x=0,1, 2, atomic fraction, %) and Zr61.5Cu21.5Fe5Al12 bulk metallic glasses (BMGs) rods with diameters of 2 and 3 mm were fabricated by copper mold casting. In order to improve the plasticity of the Zr61.5Cu21.5Fe5Al12 BMG, minor Sn and Nb with lower thermal neutron cross- sections was added into the Zr-Cu-Fe-Al alloy. The experimental results showed that the glass- forming abilities of the BMGs with Sn and Nb elements were reduced slightly. Among them with Sn and Nb elements, however, Zr61.5Cu19.5Fe5Al11Sn1Nb2 BMG exhibits high compressive strength, high ductility together with extensive“work hardening”. HRTEM study verifies the glassy states of both Zr61.5Cu19.5Fe5Al11Sn1Nb2 and Zr61.5Cu21.5Fe5Al12 alloys samples. The difference between the microstructures of the BMGs samples with and without Sn and Nb elements is that the atomic arrangement in Zr61.5Cu19.5Fe5Al11Sn1Nb2 BMG is more closely than that in Zr61.5Cu21.5Fe5Al12 BMG. Positron annihilation lifetime spectroscopy study showed further that the Zr61.5Cu19.5Fe5Al11Sn1Nb2 BMG has more closely atomic arrangement than the Zr61.5Cu21.5Fe5Al12 BMG. The structural free-volume size of the former BMG is smaller than that of the latter BMG. And the total free-volume amount of the former BMG is obviously higher than that of the latter BMG. Uniformly distributed free volume is beneficial to improve the shear band formation, branching, and interactions of the Zr61.5Cu19.5Fe5Al11Sn1Nb2 BMG, which increases finally the compressive ductility of the BMG.
Subjects: Materials Science >> Materials Science (General) submitted time 2016-11-05 Cooperative journals: 《金属学报》
Abstract：采用铜模铸造方法制备了直径2和3 mm的Zr61.5Cu21.5-xFe5Al11Sn1Nbx（x=0, 1, 2 原子分数%）和Zr61.5Cu21.5Fe5Al12非晶合金棒。结果表明， Sn和Nb微合金化略微降低了Zr-Cu-Fe-Al非晶合金的玻璃形成能力。Zr61.5Cu19.5Fe5Al11Sn1Nb2非晶合金具有优异的压缩塑性，并且表现出“应变硬化”现象。高分辨透射电镜显示Zr61.5Cu19.5Fe5Al11Sn1Nb2和Zr61.5Cu21.5Fe5Al12合金均为完全非晶态，Sn和Nb微合金化后合金内部原子排列更紧密。正电子湮没谱分析结果表明，与Zr61.5Cu21.5Fe5Al12非晶合金相比，Zr61.5Cu19.5Fe5Al11Sn1Nb2非晶合金内部原子密排间隙和结构自由体积尺寸减小、总量增加。大量弥散分布的自由体积有利于Zr61.5Cu19.5Fe5Al11Sn1Nb2非晶合金剪切带的形成、分枝和相互作用，最终改善了非晶合金的塑性。
Subjects: Computer Science >> Integration Theory of Computer Science submitted time 2022-05-11 Cooperative journals: 《计算机应用研究》
Abstract： To study the influence of disaster factors such as temperature, smoke, and CO concentration on evacuation at the fire scene, established a fire evacuation model based on the dynamic coupling of FDS and cellular automata. Mapped the grid of FDS and the cell of cellular automata one by one, and loaded the disaster data obtained from the operation of FDS into the cell in real-time through Python and other technical means, so that the disaster data can continuously affect the pedestrian transfer probability, to realize the dynamic coupling between disaster and evacuation; Taking the single-story teaching building as the simulation scene for simulation analysis, discussed the factors such as fire source location and heat release rate, and obtained the influence law of these factors on pedestrian evacuation process; Compared the model with traditional software and similar schemes to compare their similarities and differences. The research shows that the high temperature and smoke caused by fire will affect the choice of pedestrian evacuation path and emergency exit; The greater the heat release rate, the earlier pedestrians are in danger, and the more pedestrians are in danger at the same time; Compared with the traditional evacuation software, the model can not only consider the dynamic impact of the disaster causing factors caused by fire on pedestrian evacuation but also determine the location and time of pedestrians in the first dangerous state, which can be displayed visually.
Subjects: Biology >> Zoology submitted time 2018-12-20 Cooperative journals: 《动物营养学报》
Abstract：本试验旨在研究枸杞多糖对生长獭兔屠宰性能、免疫器官发育及肉质性状的影响。试验选择40日龄獭兔80只（公母各占1/2），随机分为4组（每组20个重复，每个重复1只），对照组饲喂基础饲粮，试验组分别在基础饲粮基础上添加0.1%、0.2%、0.3%的枸杞多糖。预试期5 d，正试期30 d。结果表明：1）与对照组相比，试验组半净膛率和全净膛率均有所提高，但差异不显著(P>0.05)。2）脾脏指数随枸杞多糖添加水平的增加呈上升趋势，以0.3%组最高，胸腺指数以0.2%组最高，但各组间差异均不显著(P>0.05)。3）与对照组相比，试验组肌肉滴水损失率、蒸煮损失率、剪切力和亮度(L*)值略有降低，宰后45 min和宰后24 h的pH略有上升，但差异均不显著（P>0.05）；与对照组相比，0.1%、0.2%、0.3%组肌肉红度(a*)值分别提高1.85%、5.86%、10.80%（P>0.05），黄度（b*）值分别降低10.79%、7.39%、11.93%（P>0.05）。综合分析认为，饲粮中添加枸杞多糖对生长獭兔的屠宰性能无显著影响，但能在一定程度上提高免疫器官指数，改善其肉质性状，推荐添加量为0.3%。
Subjects: Biology >> Bioengineering submitted time 2018-02-11 Cooperative journals: 《中国生物工程杂志》
Abstract：目的：制备负载NGF的可注射壳聚糖透明质酸复合水凝胶，探讨其理化性能以及生物相容性。方法：首先京尼平交联制备壳聚糖透明质酸复合水凝胶材料，采用倒置法检测凝胶时间；扫描电镜观察材料形态结构；NGF释放实验、体外溶胀以及降解实验等检测凝胶材料的物理化学性能；通过MTT实验、NGF活性检测、材料与细胞共培养检测凝胶材料生物学性能。结果：在37℃条件下，可注射凝胶材料凝胶时间在37min左右，凝胶材料为多孔网络状结构，凝胶材料8周最多能够降解76％，缓释21天的NGF具有生物活性，凝胶材料能促进RSC96细胞的粘附、增殖、迁移以及细胞活性物质的释放。结论：京尼平交联的壳聚糖透明质酸水凝胶具有良好的生物相容性，能作为NGF的载体材料，具有成为神经导管内填充材料的潜能。
Subjects: Medicine, Pharmacy >> Preclinical Medicine submitted time 2017-12-07 Cooperative journals: 《南方医科大学学报》
Abstract： Objective To explore the clinical characteristics of cataract surgery after radial keratotomy (RK) and appropriate calculation of intraocular lens (IOL) power. Methods Eight patients with cataract (12 eyes) after RK were treated in our hospital from March, 2010 to June, 2013. The visual acuity, keratometric power and length of the ocular axis were examined before the operation. For each patient, 3 groups of corneal curvature values were measured using a automatic keratometer (TOPCON-KR8800) and the minimal K value was selected. Myopic or hyperopic posterior chamber IOL (-1.00 to -2.00 D) were selected based on automatic calculations with SRK-T. Phacoemulsification and IOL implantation were then performed, and the patients were followed up for visual acuity and refractive statuses at 3 months after the operation. Results All the 12 operated eyes showed improved visual acuity after the operation. The uncorrected visual acuity reached 0.8 to 1.0 in 6 eyes and 0.4 to 0.6+ in the other 6, with a corrected visual acuity ranging from 0.6 to 1.0. The refractive status after operations was nearly emmetropic (+0.75 to -1.00 D) in 6 eyes and myopic in the other 6 (-1.00 to -2.50 D). Conclusions Phacoemulsification and IOL implantation is feasible in cataract patients with previous RK. Selecting the minimal K values for central corneal curvature and calculation of the IOL power using the SRK T equation with a reservation of -1.00 to -2.00 D can better ensure the safety of the procedure and avoid the occurrence of hyperopia >+3.00D.
Subjects: Biology >> Botany >> Applied botany submitted time 2022-06-07 Cooperative journals: 《广西植物》
Abstract： The naturalization and invasion of alien species have caused a serious impact on the global environment and social development, and have become a global problem faced by countries in biodiversity management and ecological conservation. China is one of the countries most seriously affected by alien invasion, and the situation is serious in the early warning ， management and governance of alien invasion. Based on field surveys and literature research, Chenopodiastrum murale (L.) S. Fuentes, Uotila & Borsch, an alien invasive plant of Amaranthaceae sensu lato, is first reported for flora of China. C. murale is native to the Mediterranean region and has spread to more than 40 countries in Europe, America, Africa and Oceania. It is an invasive alien plant with great harm, and it is also clearly prohibited by customs and quarantine departments. This exotic invasive plant is now found in Chenggong District, Kunming City, Yunnan Province. This paper describes the morphological characteristics of the species in detail, as well as brief introduction of its taxonomical history, and provides field ecological photos for identification and comparison. In addition, the possible introduction route of C. murale was analyzed, and its potential harm and invasive risks are briefly assessed. This new record clearly demonstrate that the background survey of Chinese alien invasive plants is still insufficient.
Subjects: Biology >> Zoology submitted time 2018-12-24 Cooperative journals: 《动物营养学报》
Abstract：本试验旨在通过消化试验来评定早稻和晚稻在生长獭兔上的营养价值。选择18只60日龄、平均体重为（1.50±0.20） kg的健康状况良好的白色獭兔，随机分为3组（每组6个重复，每个重复1只），分别饲喂基础饲粮、早稻饲粮（85%基础饲粮+15%早稻）、晚稻饲粮（85%基础饲粮+15%晚稻）。预试期和正试期各7 d。采用全收粪法测定生长獭兔对早稻和晚稻中主要营养物质的表观消化率。结果显示：1）早稻与晚稻中总能（GE）、干物质（DM）、粗蛋白质（CP）、粗脂肪（EE）、粗纤维（CF）、中性洗涤纤维（NDF）、酸性洗涤纤维（ADF）、酸性洗涤木质素（ADL）、粗灰分（Ash）、钙（Ca）、磷（P）、无氮浸出物（NFE）的含量分别为16.25 MJ/kg、86.32%、7.82%、1.32%、8.54%、23.35%、10.54%、1.54%、1.32%、0.53%、0.38%、64.76%与16.07 MJ/kg、89.17%、6.88%、1.32%、9.07%、24.55%、11.57%、2.01%、3.96%、0.62%、0.21%、63.71%。2）早稻和晚稻在生长獭兔中的表观消化能分别为10.43和10.32 MJ/kg，生长獭兔对早稻和晚稻中GE、DM、CP、EE、CF、NDF、ADF、Ash、Ca、P、NFE的表观消化率分别为65.33%、74.32%、76.69%、68.59%、13.12%、38.63%、27.11%、52.23%、50.03%、15.54%、74.35%与64.22%、76.15%、70.92%、72.93%、14.35%、38.49%、27.09%、52.03%、48.63%、14.99%、73.64%。由上可知，早稻和晚稻中主要营养物质含量差异较小，生长獭兔对早稻和晚稻主要营养物质的表观消化率基本相当；早稻和晚稻均可以作为生长獭兔的能量饲料来源，二者对生长獭兔的营养价值相近。
Subjects: Other Disciplines >> Synthetic discipline submitted time 2023-03-28 Cooperative journals: 《中国科学院院刊》
Abstract： The cross-border railways and oil and gas pipelines along the China-Mongolia-Russia Economic Corridor are key hubs and channels supporting the regional cooperation and development. It is very important to complete scientific regionalization of ecological risk of China-Mongolia-Russia Economic Corridor and put forward suggestions to guarantee smooth construction and safe cross-border traffic project. By establishing ecological risk evaluation model, we quantitatively analyzed the ecological risk of China Mongolia#2;Russia Economic Corridor, and regionalized high, middle, and low risk. We put forward the ecological risk prevention and control countermeasures for China-Mongolia-Russia Economic Corridor. It shows that the ecological risk areas are distributed along the “two belts and one line”. The risk of desertification is along the China-Mongolia-Russia cross-border traffic belt, the risk of permafrost is along the China-Russia cross-border traffic belt and the China-Russian crude oil pipeline. The proposed suggestions are designated to prevent and control ecological risk from the perspectives of promoting ecological civilization to realize a “two-highs and three-lows” mode; constructing of a green economic corridor, optimizing the industrial structure, actively establishing a four-tier circular economy system, and developing green circular industries; innovating technical biological engineering; establishing system and mechanism of an international cooperation and monitoring ecological risk network system along China-Mongolia-Russia Economic Corridor. We provide scientific technic support for rationally building cross-border railways and pipelines, avoiding and preventing ecological risks in China#2;Mongolia-Russia Economic Corridor. It will be decision-making basis to promote regional green and sustainable development.
Subjects: Medicine, Pharmacy >> Clinical Medicine submitted time 2022-10-13 Cooperative journals: 《中国全科医学》
XU Yi-fan
JING Li-mei
WANG Li-li
WANG Zhao-lin
LI Yu-han
LU Wen-yuan
ZHANG Qin-hua
WANG Hao-ran
JING Jia-heng
LI Shui-jing
Abstract： Background:In the initial stage of hospice care pilot work in China, it is urgent to comprehensively evaluate the quality and effect of hospice care services of different institutions.Objective:To establishacomprehensive evaluation index system ofhospice care service in the maso-level.Method:The index systemwas determined by literature research,thematic framework analysisand Delphimethod. Results:After two rounds of expert consultation, the finalized index system contains 3 first-level indexes (structure, process and outcome), 9 second-level indicators (such as policy, service provision, affordability of patients), 25 third-level indicators (such as the presence and effectiveness of policy and strategy, service quantity, average cost) and 81 fourth-level indicators (such as the existence of institutional development plan,number of discharged patients in hospice care, per capita medical expenses of discharged patients in hospice care).The effective recoveries rate of the first round of expert consultation questionnaires was 93.33%, the expert authority coefficient was0.900,Kendall's W coefficients of fourth-level indicators were 0.194, 0.115, 0.126, respectively. The effective recoveries rate of the second round of expert consultation questionnaires was 92.86%, the expert authority coefficient was0.900,Kendall's W coefficients of fourth-level indicators were 0.417, 0.241, 0.322, respectively. Conclusion:Based on "structure-process-outcome" framework, The comprehensive evaluation index system of hospice care services constructed in this study had innovation and practicability. In addition, itwas conducive to comprehensively evaluate the quality and effect of different institutions, which lays a good foundation for promotion of the regional equalization and institutional homogenization.
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