检索结果-南通市图书馆

在线全文

学校读者我要写书评

暂无评论

肥胖全基因组关联研究的现状与展望

中华流行病学杂志 2010年第12期31卷 1425-1428页

作者：席波米杰首都儿科研究所流行病学研究室北京100020

常见复杂性疾病,又称多基因疾病,是由多对微效基因与环境因素共同作用所致,具有明显的遗传异质性、表型复杂性及种族差异性等特征.常见复杂性疾病和单基因疾病的一个最显著的区别是,它不依照经典的孟德尔模式遗传.伴随着生活环境的改变... 详细信息

常见复杂性疾病,又称多基因疾病,是由多对微效基因与环境因素共同作用所致,具有明显的遗传异质性、表型复杂性及种族差异性等特征.常见复杂性疾病和单基因疾病的一个最显著的区别是,它不依照经典的孟德尔模式遗传.伴随着生活环境的改变,发展中国家正经历着流行病由过去严重传染性疾病向常见慢性疾病的转移[1].以肥胖为例,1980-2002年期间,美国20岁以上成年人的肥胖率增加了1倍 6～19岁儿童青少年的超重率增加了2倍[2].2006年世界卫生组织（WHO）数据显示,世界肥胖人群已逾4亿[3].

关键词：肥胖全基因组关联研究体脂和肥胖相关基因

安徽芜湖湾沚区再生稻生产实践与发展策略探讨

在线全文

学校读者我要写书评

暂无评论

中国种业 2025年第1期 44-47页

作者：奚波张永文安徽省芜湖市湾沚区农业技术推广中心芜湖241100

再生稻是指在上一季水稻收割后,对稻桩上的休眠芽抽生出来的再生蘖加以培育,以达到出穗成熟的一种栽培方法,作为水稻的一种轻简化高效种植模式,在我国有着悠久的历史。其因有“一种两收三高四省”的突出优点而得到广泛应用,即播一次种,... 详细信息

再生稻是指在上一季水稻收割后,对稻桩上的休眠芽抽生出来的再生蘖加以培育,以达到出穗成熟的一种栽培方法,作为水稻的一种轻简化高效种植模式,在我国有着悠久的历史。其因有“一种两收三高四省”的突出优点而得到广泛应用,即播一次种,收获两季,投入产出率高、劳动效率高、经济效益高,省工、省种、省肥、省田。近年来随着再生稻的推广,安徽省芜湖市湾沚区再生稻种植面积逐步扩大,结合多年从事再生稻推广经验,通过总结芜湖市湾沚区再生稻生产现状,分析其存在的主要问题,具体包括再生稻专用品种缺乏、育插秧能力不足、全产业链发展乏力等,提出发展再生稻产业的对策建议。

关键词：再生稻生产现状对策建议芜湖市湾沚区

Density enhancement mechanism of upwind schemes for low Mach number flows

在线全文

学校读者我要写书评

暂无评论

Acta Mechanica Sinica 2018年第3期34卷 431-445页

作者： bo-xi Lin Chao Yan Shu-Sheng Chen School of Aeronautic Science and Engineering Beihang University

Many all-speed Roe schemes have been proposed to improve performance in terms of low speeds. Among them, the F-Roe and T-D-Roe schemes have been found to get incorrect density fluctuation in low Mach flows, which is expected to be with the square of Mach number. Asymptotic analysis presents the mechanism of how the density fluctuation problem relates to the incorrect order of terms in the energy equation paU△U. It is known that changing the upwind scheme coefficients of the pressure-difference dissipation term DP and the velocity-difference dissipation term in the momentum equation DPU to the order of O （c- 1） and O（c0） can improve the level of pressure and velocity accuracy at low speeds. This paper shows that corresponding changes in energy equation can also improve the density accuracy in low speeds. We apply this modification to a recently proposed scheme, TV-MAS, to get a new scheme, TV-MAS2. Unsteady Gresho vortex flow, double shear-layer flow, low Mach number flows over the inviscid cylinder, and NACA0012 airfoil show that energy equation modification in these schemes can obtain the expected square Ma scaling of density fluctuations, which is in good agreement with corresponding asymptotic analysis. Therefore, this density correction is expected to be widely implemented into allspeed compressible flow solvers.

关键词： Energy equation Density fluctuation Roe TV-MAS Low speeds All speeds Computational fluid dynamics

Corrosion evaluation and resistance study of alloys in chloride salts for concentrating solar power plants

在线全文

学校读者我要写书评

暂无评论

Rare Metals 2024年第3期43卷 1222-1233页

作者： Dong-Mei Han Yong Shuai Bachirou Guene Lougou bo-xi Geng xi-bo He Tian-Tian Yan Jia-Meng Song School of Energy Science and Engineering Harbin Institute of TechnologyHarbin150001China

Thermal energy storage(TES)systems based on molten salt are widely used in concentrating solar power(CSP)*** investigation of the corrosion behavior of alloy materials in molten salt is crucial for the correct selection of alloy materials and the design of TES *** this study,the corrosion behavior of 304,310S,316,and In625 alloys in molten chloride salts(27 mol%NaCl-22 mol%KCl-51 mol%MgCl,)was *** evolution of mass loss of the alloy samples with corrosion time and temperature and the analysis of the experimental results by scanning electron microscopy(SEM),energy dispersive spectrometer(EDS),and X-ray diffraction(XRD)revealed the corrosion mechanism of the alloy samples in molten chloride *** main factors affecting the corrosion of the alloy samples were further *** was found that the loose multi-layer corrosion was formed on the surface of the corroded alloy samples with the increase in corrosion ***,the experimental *** that Mo played a positive role in improving the corrosion resistance of the alloy samples because the presence of Mo could inhibit the outward diffusion of alloying element *** work enriches the molten salt corrosion database and provides a reference for the selection of alloy materials for TES systems with potential application in CSP plants.

关键词： Thermal energy storage Molten chloride salt Alloy materials Corrosion mechanism Corrosion resistance

Characterization of the Growth,Chlorophyll Content and Lipid Accumulation in a Marine Microalgae Dunaliella tertiolecta under Different Nitrogen to Phosphorus Ratios

在线全文

学校读者我要写书评

暂无评论

Journal of Ocean University of China 2016年第1期15卷 124-130页

作者： SONG Donghui xi bo SUN Jing Tianjin Key Laboratory of Marine Resources and Chemistry College of Marine and Environmental SciencesTianjin University of Science & Technology

Microalgal lipids are regarded as main future feedstock of biofuels for its higher efficiency of accumulation and sus- tainable production. In order to investigate the effect of various nitrogen to phosphorus ratios on cells growth, chlorophyll content and accumulation of lipids in Dunaliella tertiolecta, experiments were carried out in modified microalgal medium with inorganic nitrogen （nitrate-nitrogen） or organic nitrogen （urea-nitrogen） as the sole nitrogen source at initial N：P ratios ranging from 1：1 to 32：1. The favorable N：P of 16：1 in the nitrate-N or urea-N medium yielded the maximum cell density and specific growth rate. Decrease in chlorophyll content were observed at the N：P of 4：1 in both nitrate-N and urea-N cultures. It was also observed that the maximum lipids concentration was obtained at the N：P of 4：1 in both nitrate and urea nutrient medium. The lipid productivity and lipid content of cultures in the urea-N medium at the N：P of 4： lwere markedly higher than those from cultures with other N：P ratios （p〈 0.05）. The results of this work illustrate the possibility that higher ratios of nitrogen to phosphorus have enhancing effect on cells growth of D. tertiolecta. Conversely, higher lipid accumulation is associated with a decrease in chlorophyll content under lower ratios of nitro- gen to phosphorus. The results confirm the hypothesis of this study that a larger metabolic flux has been channeled to lipid accumu- lation in D. tertiolecta cells when the ratios of nitrogen to phosphorus drop below a critical level.

关键词： Dunaliella tertiolecta lipid accumulation ratios of nitrogen and phosphorus concentration

Quality of service aware admission control in cognitive device-to-device network

在线全文

学校读者我要写书评

暂无评论

The Journal of China Universities of Posts and Telecommunications 2011年第5期18卷 22-29,36页

作者： FU Zi-xi HU Chun-jing PENG Tao LU Qian-xi WANG Wen-bo Wireless Signal Processing and Network Lab Key Laboratory of Universal Wireless Communication Ministry of Education Beijing University of Posts and Telecommunications Beijing 100876 China

A hybrid system of cellular mode and device-to-device （D2D） mode is considered in this paper, where the cellular resource is reused by the D2D transmission. With the objective of capacity maximization, the power optimization of D2D sub-system is considered, taking into account quality of service （QoS） requirement. The power optimization problem is divided into two stages： The first stage is the admission control scheme design based on the QoS requirement of D2D users, and the second is power allocation to maximize aggregate throughput of admissible D2D users. For the D2D admission control problem, a heuristic sorting-based algorithm is proposed to index the admissible D2D links, where gain to Interference ratio （GIR） sorting criterion is used. Applying an approximate form of Shannon capacity, the power allocation problem can be solved by convex optimization and geometric programming tools efficiently. Based on the theoretical analysis, a practical algorithm is proposed. The precision can reach a trade-off between complexity and performance. Numerical simulation results confirm that combining with GIR sorting method, the proposed scheme can significantly improve the D2D system＇s capacity and fairness.

关键词： cognitive radio QoS power control geometric programming sorting-based algorithm

Effect of rich air/fuel ratio and temperature on NO_x desorption of lean NO_x trap

在线全文

学校读者我要写书评

暂无评论

Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2013年第11期14卷 835-842页

作者： Lei LIU Zhi-jun LI Hong-yang ZHANG Qing CHANG bo-xi SHEN State Key Laboratory of Engines Tianjin University

An experimental and model-based study of the effect of rich air/fuel ratios(AFRs) and temperature on the NOx slip of a lean NOx trap(LNT) was conducted in a lean-burn gasoline engine with an LNT after-treatment system. The emissions of the engine test bench and the inlet temperature of the LNT were used as the major inlet boundary conditions of the LNT. The engine periodically operated between a constant lean AFR of 23 with alterable rich AFRs of 10, 11, 12, 13, and 14. A decrease in the rich AFR of the engine strengthened the desorption atmosphere in the LNT, an effect closely related to the number of reductants, and further heightened the NOx desorption of the LNT, but with a penalty in fuel consumption. To eliminate that penalty, the inlet boundary conditions of the LNT were varied by adjusting the inlet temperature within a range between 200℃ and 400℃. An increase in inlet temperature heightened the NOx desorption of the LNT, and a NOx breakthrough occurred after the inlet temperature exceeded 390℃. To control NOx breakthrough, the inlet temperature can be adjusted to offset the strong desorption atmosphere in the LNT commonly created by a rich AFR.

关键词： Lean NOx trap (LNT) Air/fuel ratio (AFR) Temperature NOx adsorption NOx desorption

A Chaotic Neural Network Model

在线全文

学校读者我要写书评

暂无评论

Chinese Physics Letters 1996年第3期13卷 185-188页

作者： SHUAI Jian-wei CHEN Zhen-xiang LIU Rui-tang WU bo-xi Department of Physics Xiamen UniversityXiamen 361005

A chaotic neural network model is introduced in this *** the variation of a controlling parameter,the model can process the input by a content-addressable means or fall into a chaotic *** the features of brain such as... 详细信息

关键词： state. chaotic letter

Yinchenhao decoction attenuates obstructive jaundice-induced liver injury and hepatocyte apoptosis by suppressing protein kinase RNA-like endoplasmic reticulum kinase-induced pathway

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

World Journal of Gastroenterology 2019年第41期25卷 6205-6221页

作者： Yan-Li Wu Zhong-Lian Li xi-bo Zhang Hao Liu Graduate School of Tianjin Medical University Tianjin 300070China Department of Hepatobiliary and Pancreatic Surgery Tianjin Nankai HospitalTianjin 300100China

BACKGROUND Chronic biliary obstruction results in ischemia and hypoxia of hepatocytes,and leads to *** is very important in regulating the homeostasis of the hepatobiliary *** reticulum(ER)stress is one of the signaling pathways that induce ***,the protein kinase RNA-like endoplasmic reticulum kinase(PERK)-induced apoptotic pathway is the main way;but its role in liver injury remains *** decoction(YCHD)is a traditional Chinese medicine formula that alleviates liver injury and apoptosis,yet its mechanism is *** undertook this study to investigate the effects of YCHD on the expression of ER stress proteins and hepatocyte apoptosis in rats with obstructive jaundice(OJ).AIM To investigate whether YCHD can attenuate OJ-induced liver injury and hepatocyte apoptosis by inhibiting the PERK-CCAAT/enhancer-binding protein homologous protein(CHOP)-growth arrest and DNA damage-inducible protein 34(GADD34)pathway and B cell lymphoma/leukemia-2 related X protein(Bax)/B cell lymphoma/leukemia-2(Bcl-2)*** For in vivo experiments,30 rats were divided into three groups:control group,OJ model group,and YCHD-treated *** was collected to detect the indicators of liver function,and liver tissues were used for histological *** in vitro experiments,30 rats were divided into three groups:G1,G2,and *** rats in group G1 had their bile duct exposed without ligation,the rats in group G2 underwent total bile duct ligation,and the rats in group G3 were given a gavage of *** to the serum pharmacology,serum was extracted and centrifuged from the rat blood to cultivate the BRL-3A *** deoxynucleotidyl transferase mediated dUTP nick end-labelling(TUNEL)assay was used to detect BRL-3A hepatocyte *** aminotransferase(ALT)and aspartate transaminase(AST)levels in the medium were *** blot and quantitative real-time polymerase chain reaction(qRT-PCR)analyses were

关键词： Yinchenhao decoction Obstructive jaundice Liver injury Apoptosis Protein kinase RNA-like endoplasmic reticulum kinase CCAAT/enhancer-binding protein homologous protein Growth arrest and DNA damage-inducible protein 34 B cell lymphoma/leukemia-2 gene B cell lymphoma/leukemia-2 gene related Ⅹ protein