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农村“空巢”老年人居住方式影响因素研究

经济问题 2017年第2期450卷 68-74页

作者：仇志娟杜昊上海对外经贸大学法学院上海201620 上海市委党校第四分校上海200042

利用全国妇联和国家统计局2010年"第三期中国妇女社会地位调查"全国样本数据,对农村老年人的居住方式问题进行了实证研究。当前农村老年人空巢居住意愿为三成左右,但实际上的空巢居住方式占五成以上,居住意愿与居住方式不一致性显著。... 详细信息

利用全国妇联和国家统计局2010年"第三期中国妇女社会地位调查"全国样本数据,对农村老年人的居住方式问题进行了实证研究。当前农村老年人空巢居住意愿为三成左右,但实际上的空巢居住方式占五成以上,居住意愿与居住方式不一致性显著。为解释这一现象,通过建立有序的logistic回归模型对农村老年人居住方式的影响因素进行了分析,结果表明:主观居住意愿对老年人居住方式有显著的影响,客观因素对居住方式的影响存在性别差异,婚姻状况、主要生活来源、社会养老保障情况、拥有自主产权住房情况、身体健康状况和日常生活是否需要照料、家中是否有少年儿童对农村男性老年人居住方式存在显著影响;婚姻状况、现住房归属情况、身体健康状况、女儿数量和家中是否有少年儿童对农村女性老年人居住方式存在显著影响。

关键词：农村老年人居住意愿性别

Body-force modeling considering induced upstream effects for a transonic compressor with total temperature distortion

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Chinese Journal of Aeronautics 2024年第6期37卷 7-19页

作者： Jiahui qiu Chen YANG Wenqiang ZHANG Min ZHANG juan du Digital Twin Research Center Institute of Engineering ThermophysicsChinese Academy of SciencesBeijing 100190China School of Engineering and Science University of Chinese Academy of SciencesBeijing 100190China National Key Laboratory of Science and Technology on Advanced Light-duty Gas-turbine Chinese Academy of SciencesBeijing 100190China School of Mechatronical Engineering Beijing Institute of TechnologyBeijing 100081China

To numerically study the impact of total temperature distortion on a transonic compressor with reduced computational costs,a Body-Force Model(BFM)is ***,the interactions between the distorted flow and the compressor are analyzed using full-annulus Unsteady Reynolds-Averaged Navier-Stokes(URANS)results and the orbit *** is found that the induced swirl distortion and the mass flux nonuniformity are intensified in the compressor upstream flow field.A correction factor is thus added to the BFM to account for the effect of the induced swirl,which is crucial for the accurate representation of distortion transfer in the ***,steady simulations with large-amplitude 180circumferential total temperature distortion are performed using the developed *** is shown that the distorted compressor map simulated with the BFM matches well with URANS *** circumferential phase shift of total temperature and the generation of the additional total pressure distortion across the rotor are in line with the time-averaged URANS flow *** compressor upstream effects on the distorted inflow can also be exactly *** above-mentioned results demonstrate the BFM developed in this paper can effectively capture the distorted flow features inside the compressor,and significantly reduce the computational costs by five orders of magnitude compared with URANS.

关键词： Upstream effect Orbit method Induced swirl distortion Body force model Correction factor Time-averaged URANS

Design Optimization of Non-Axisymmetric Vane for an Axial Compressor under Inlet Distortion

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Journal of Thermal Science 2023年第4期32卷 1321-1334页

作者： ZHANG Min du juan ZHAO Hongliang qiu Jiahui BA dun CHEN Yang NIE Chaoqun Digital Twin Research Center Institute of Engineering ThermophysicsChinese Academy of SciencesBeijing100190China Key Laboratory of Advanced Energy and Power Chinese Academy of SciencesBeijing100190China Innovation Academy for Light-duty Gas Turbine Chinese Academy of SciencesBeijing100190China School of Engineering Science University of Chinese Academy of SciencesBeijing100049China

The flow field at the inlet of compressors is generally encountered combined total pressure and swirl distortion for either aircraft engine with S-duct or gas turbine with lateral air *** inevitably deteriorates compressor aerodynamic performance,including not only the efficiency or pressure ratio but also the operation *** order to conquer this issue,appropriate measures such as integrating flow control techniques and modifying inlet or compressor design are of *** to this motivation,this article develops a full-annular two-dimensional(2D)and a partial-annular three-dimension(3D)optimization strategy for non-axisymmetric vane ***,two numerical simulation methods for evaluating performance of full-annular 2D vane and compressor with partial-annular 3D vane are *** swirl patterns at the inlet of a 1.5-stage axial compressor are analyzed and parametrized,and the parameterization is transferred to characterize the circumferential distribution of geometrical parameters of the vane *** approaches dramatically reduce computational simulation costs without violating the non-axisymmetric flow distortion *** various full-annular 2D sections at different radial locations are constructed as design *** designed vane is reconstructed and 3D numerical simulations are performed to examine performance of the non-axisymmetric vane and the compressor with ***,partial annular 3D optimization is conducted for balancing compressor efficiency and stall *** indicate that the designed non-axisymmetric vane based on full-annular optimization approach can decrease the vane total pressure loss under the considered inlet flow distortion,while those using partial-annular optimization achieve positive effects on compressor stall margin.

关键词： combined total pressure and swirl distortion axial compressor non-axisymmetric vane optimization aerodynamic performance

Stall Behaviour in a Mixed-flow Compressor with Axial Slot Casing Treatment

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Journal of Thermal Science 2022年第1期31卷 13-24页

作者： qiu Jiahui ZHANG Qianfeng ZHANG Min du juan ZHANG Wenqiang MAROLDT Niklas SEUME Joerg R. Advanced Gas Turbine Laboratory Institute of Engineering ThermophysicsChinese Academy of SciencesBeijing 100190China Key Laboratory of Advanced Energy and Power Chinese Academy of SciencesBeijing 100190China Innovation Academy for Light-duty Gas Turbine Chinese Academy of SciencesBeijing 100190China School of Engineering Science University of Chinese Academy of SciencesBeijing 100049China China Aerodynamics Research and Development Center Beijing 100029China University of Nottingham Nottingham NG72RDEngland Institute of Turbomachinery and Fluid Dynamics Leibniz University HannoverGarbsen 30823Germany

Casing treatment is an effective technique in extending stall margin of axial and centrifugal ***,its impacts on the stall behaviour of mixed-flow compressor are still not completely understood until *** conquer this issue,unsteady full-annulus simulations were conducted to investigate the stall mechanism of a mixed-flow compressor with and without axial slot casing treatment(ASCT).The circumferential propagating speed of spike inception resolved by the numerical approach is 87.1%of the shaft speed,which is identical to the test *** numerical results confirmed that the mixed-flow compressor fell into rotating stall via spike-type with and without *** flow structure of the spike inception was investigated at 50%design rotational *** static pressure traces extracted upstream of the leading edge had shown a classic spiky ***,it was found that with and without ASCT,the mixed-flow compressor stalled through spike with the characteristic of tip leakage spillage at leading edge and tip leakage backflow from trailing edge,which is different from a fraction of the centrifugal *** resultant phenomenon provides conoborating evidence for that unlike in axial-flow compressor,the addition of ASCT does not change the stall characteristics of the mixed-flow *** flow structure that induced spike inception with ASCT is similar to the case with smooth *** the throttling process,tip leakage flow vortex had been involved in the formation of tornado vortices,with one end at the suction side,and the other end at the *** low-pressure region relevant to the downward spike is caused by leading-edge separation vortex or tornado *** high-pressure region relevant to the upward spike is induced by blockage from the passage *** results not only can provide guidance for the design of casing treatment in mixed-flow compressor,but also can pave the way for the stall waring in the highly-l

关键词： mixed-flow compressor casing treatment spike-type stall inception unsteady simulation tornado vortex

The Effect of Yucca schidigera Extract on Ruminal Fermentation and Parameters Traits in Sheep

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Agricultural Sciences in China 2007年第1期6卷 121-128页

作者： LIU Chun-long LI Zhong-qiu du juan SHAN An-shan Animal Nutrition Institute Northeast Agricultural University Harbin 150030 P.R.China Northeast Institute of Geography and Agricultural Ecology Chinese Academy of Sciences Harbin 150080 P.R.China Department of Animal Science Research Heilongjiang Academy of Agricultural Sciences Harbin 150086 P.R. China

In a completely randomized block design experiment, 16 ruminally cannulated sheep （40 ±2.1 kg）fed a 50% concentrate： 50% forage diet （DM basis） were given intraruminal doses of powdered Yucca schidigera extract （YSE）. Doses of 0 （control）, 100, 200, or 300 mg kg^-1 diet were given at 8 p.m. and 4 a.m. On 15, 16, and 17 d of the experimental period, ruminal contents were sampled 0, 2, 4, 6, and 8 h after dosing, and blood samples were collected at the end of the experiment （18th and 19th d）. Acidity was not affected （P〉0.05） by the addition of YSE. Compared with the control, ruminal propionate concentration was increased by 29.4 and 29.8% （P〉 0.05） and the acetic acid concentration was decreased by 15.1 and 19.8% （P〉0.05） at 4 and 6 h after YSE （300 mg kg^-1） dosing, respectively. Ruminal ammonia concentration in the first 2 h after feeding was higher （P〈0.05） in the sheep that did not receive YSE （increased by 17.57 mg 100 mL^-1） than in those that received 200 mg kg^-1（increased by 6.77 mg 100 mL^-1） or 300 mg kg^-1 （increased by 6.50 mg 100 mL^-1） YSE. Protozoan populations in the rumen were lower （P〈0.05） in the animals that received 300 mg kg^-1 of YSE compared with the control. All serum parameters of the four groups were in the normal range and were similar among the treatment groups （P 〉 0.05）, after being fed for 19 d with different doses of YSE. The effect of YSE on ruminal ammonia concentration likely resulted from a decreased concentration of protozoan populations and, presumably, from ammonia binding by YSE.

关键词： Yucca schidigera extract rumen fermentation protozoan populations serum parameters sheep

On the convergence for PNQD sequences with general moment conditions

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Applied Mathematics(A Journal of Chinese Universities) 2020年第2期35卷 184-192页

作者： XIAO juan qiu De-hua School of Mathematics and Statistics Hengyang Normal UniversityHengyang 421008China School of Statistics and Mathematics Guangdong University of Finance and EconomicsGuangzhou 510320China

Let fX;Xn;n≥1g be a sequence of identically distributed pairwise negative quadrant dependent(PNQD)random variables and fan;n1g be a sequence of positive constants with an=f(n)and f(θ^k)=f(θ^k-1)for all large positive integers k,where 10(x≥1)is a non-decreasing function on[b;+1)for some b≥1:In this paper,we obtain the strong law of large numbers and complete convergence for the sequence fX;Xn;n≥1g,which are equivalent to the general moment conditionΣ∞n=1P(|X|>an)<*** results extend and improve the related known works in Baum and Katz[1],Chen at al.[3],and Sung[14].

关键词： pairwise negative quadrant dependent(PNQD)random variable strong law of large numbers complete convergence general moment condition

Identification and Functional Analysis on Abiotic Stress Response of Soybean Cl^- Channel Gene GmCLCnt

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Agricultural Sciences in China 2010年第2期9卷 199-206页

作者： ZHOU Guo-an qiu Li-juan The National Key Facility for Crop Gene Resources and Genetic Improvement （NFCRI）/Key Lab of Germplasm Utilization Ministry of Agriculture/Institute of Crop Sciences Chinese Academy of Agricultural Sciences Beijing 100081 P.R.China

The Cl^- homeostasis was known as the major mechanism of soybean to achieve NaCl tolerance, but studies on the role of chloride channel under abiotic stress were relatively few. We cloned a putative CLC-type chloride channel gene GmCLCnt from soybean via RACE and it was predicted to encode a protein of 783 amino acids with 9 possible transmembrane domains and 2 tandem CBS domains. Real-time RT-PCR analysis showed that the GmCLCnt gene was expressed in all tissues of soybean but enriched in leaves and its expression was induced by NaCl, polyethylene glycol （PEG）, coldness and ABA treatments. The Arabidopsis seedlings overexpressing GmCLCnt were more tolerant to higher concentration of NaCl than those of wild type. The results suggested that the GmCLCnt may be a CLC-type chloride channel and play an important role in salt tolerance.

关键词： GmCLCnt gene chloride channel salt tolerance soybean

Structural and functional analysis of an asymmetric bidirectional promoter in Arabidopsis thaliana

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Journal of Integrative Plant Biology 2015年第2期57卷 162-170页

作者： Shi-juan Liu qiu-juan Yue Wei Zhang Key Laboratory of Plant Cell Engineering and Germplasm Innovation Ministry of Education School of Life Sciences Shandong University College of Life Science Qufu Normal University

Bidirectional promoters are relatively abundant in eukaryotic genomes, suggesting that they have an important biological significance. As yet, few of these promoters have been characterized in detail. Here, using a promoter：：GUS transgene approach has revealed that the intergenic region of Arabidopsis thaliana divergent genes At1g71850 and At1g71860 is an asymmetric bidirectional promoter, which exhibits an orientation-dependent expression profile. The strength of the forward promoter was greater than that of the reverse promoter, and their tissue specificities were not identical. Deletion analyses revealed that this bidirectional promoter could be divided into three functional regions. The basal level and tissue specificity of the promoter in the reverse orientation were regulated positively by region II and negatively by region III, whereas promoter activity in the forward orientation was regulated negatively by region II and positively by region I. Thus the 52-bp stretch of region II had a dual function, enhancing expression in the reverse orientation and suppressing it in the forward orientation. These results demonstrated that the activity of the At1g71850-At1g71860 bidirectional promoter was modulated by complex interactions between both positive and negative cis-acting elements. These findings will enhance our understanding of the regulatory mechanisms of plant bidirectional promoters.

关键词： GUS (β-glucuronidase) positive and negative regulatoryelement promoter strength tissue-specific expression

Myelin lipid deficiency:a new key driver of Alzheimer’s disease

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Neural Regeneration Research 2023年第1期18卷 121-122页

作者： Shulan qiu juan Pablo Palavicini Xianlin Han Barshop Institute for Longevity and Aging Studies Division of DiabetesDepartment of MedicineUniversity of Texas Health Science Center at San AntonioSan AntonioTXUSA

Lipids play essential biological functions that include acting as components of biological membranes,energy storage,signaling,nutrients,transporters,enzyme activators,among *** with the multiple research methods to assess DNA,RNA,and protein content,location,and function in cells,there are relatively fewer methods to study ***,lipid-oriented mechanistic studies remain rare and challenging.

关键词： Alzheimer rare challenging