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Effect of pouring height on the solidified microstructure of AlSi7Mg alloy

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Journal of University of Science and Technology Beijing 2006年第4期13卷 324-328页

作者： Weimin mao Yuelong Bai hai Lin Materials Science and Engineering School University of Science and Technology Beijing Beijing 100083 China

The effect of different pouring heights and evenly soaking process in the liquidus and solidus range on the solidified microstructure of AlSi7Mg alloy has been studied. The results show that if the pouring temperature is 630 or 650℃ and the pouring height is 40 mm, the microstructure of the solidified melt is not homogeneous and there are many rosette-like primary α-Al grains. But if the pouring height is increased to 400 mm, the solidified microstructure becomes more homogeneous and favorable to obtain spherical primary α-Al grains in the solidified melt. With further being evenly soaked in the liquidus and solidus range for some time, the temperature difference between the melt center and the melt periphery can be controlled within ±2℃ and the primary α-Al grains will evolve into more spherical grains. The theoretical analysis indicates that the higher pouring height promotes the melt flow motion and makes the temperature field in the melt more homogeneous and restrains the large rosette primary α-Al grains. This flow motion can also promote the ripening effect and the primary α-Al grains in the melt are gradually changed into spherical grains. It can be concluded from the experiments that pouring at an appropriate superheat and from a proper height is a good new method for preparing the semisolid slurry of AlSi7Mg alloy, its process control is easy and the preparation cost is lower.

关键词： AlSi7Mg alloy semisolid pouring height solidification flow motion

Analysis of the anti-T2DM components in dichloromethane fraction of Schisandra sphenanthera and its mechanism

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Traditional Medicine Research 2025年第1期10卷 27-43页

作者： Shi-Bo Feng hai-Hui Jiang Hui-Li Kang Yi Jiang Hua-Wei Zhang Xiao-Mei Song Yu-Ze Li Wen-Li huang Dong-Dong Zhang Chong Deng School of Pharmacy Shaanxi University of Chinese MedicineXianyang 712046China School of Pharmacy and Shaanxi Qinling Application Development and Engineering Center of Chinese Herbal Medicine Shaanxi University of Chinese MedicineXianyang 712046China Key Laboratory for Research and Development of“Qin Medicine”of Shaanxi Administration of Traditional Chinese Medicine Xianyang 712046China Shaanxi Key Laboratory of Research and Application of“Taibai Qi Yao” Xianyang 712046China

Background:The type 2 diabetes mellitus(T2DM)pharmacodynamic study of various parts of Schisandra sphenanthera was conducted in the previous stage,and it was found that dichloromethane extracted part(SDP)had a significant hypoglycemic ***,the components of SDP were analyzed,and the specific mechanism of its anti-T2DM was ***:We used a high-fat,high-sugar diet in combination with streptozotocin to induce a T2DM rat model,and the model rats were divided into two groups according to body weight and blood ***,oral glucose tolerance test,fasting blood glucose,low density lipoprotein cholesterol,superoxide dismutase,insulin,glycated hemoglobin,total cholesterol,nonesterified free fatty acids,alanine aminotransferase,high-density lipoprotein cholesterol,aspartate aminotransferase,malondialdehyde,and glutathione peroxidase were measured,organ indices were calculated,and pathological sections of pancreas and liver were *** 16S rRNA V3–V4 region of intestinal flora was sequenced to explore the effect of SDP on biochemical indicators and intestinal *** on the above indicators,the anti-T2DM mechanism of SDP in Schisandra sphenanthera was ***:After six weeks of administration,the biochemical indices of diabetic rats were diminished compared to the control *** SDP could significantly increase the gut microbialα-diversity index,resulting in significant changes in the flora of T2DM rats,with increased richness and diversity,reduced harmful flora,and significantly back-regulated the levels of acetic acid,propionic acid,and butyric ***:SDP can improve the symptoms associated with elevated blood glucose,dyslipidemia,elevated fasting insulin levels,and damaged glucose tolerance in *** against T2DM may be through the control of intestinal flora to normalize and exert anti-diabetic effect;its main active components may be lignans and terpenoids.

关键词： Schisandra sphenanthera T2DM intestinal flora HPLC

Thruster direction controlling of assembled spacecraft based on gimbal suspension

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Journal of Systems Engineering and Electronics 2016年第2期27卷 442-448页

作者： Hongliang Xu hai huang School of Astronautics Beihang University

The attitude control system design and its control effect are affected considerably by the mass-property parameters of the spacecraft. In the mission of on-orbit servicing, as fuel is expended, or the payloads are added or removed, the center of mass will be changed in certain axe; consequently, some thrusters＇ directions are deviated from the center of mass（CM） in certain plane. The CM of assembled spacecraft estimation and thruster direction control are studied. Firstly, the attitude dynamics of the assembled spacecraft is established based on the Newton-Euler method. Secondly, the estimation can be identified by the least recursive squares algorithm. Then, a scheme to control the thrusters＇ directions is proposed. By using the gimbal installed at the end of the boom, the angle of the thruster is controlled by driving the gimbal; therefore, thrusters can be directed to the CM again. Finally, numerical simulations are used to verify this scheme. Results of the numerical simulations clearly show that this control scheme is rational and feasible.

关键词： on-orbit servicing thruster's direction control assembled spacecraft center of mass(CM) identification

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摆式客车转向架倾摆机构及其动力学性能研究

铁道机车车辆 2003年第1期23卷 31-35页

作者：李晓燕李芾傅茂海黄运华西南交通大学牵引动力研究中心四川成都610031

介绍了国外摆式列车发展的基本概况 ,根据我国线路特点 ,提出了一种能满足我国铁路进一步提速的高速摆式客车转向架方案。文中对转向架的结构方案及其特点进行了详细的分析和说明。高速摆式客车转向架采用一系柔性定位 ,倾摆机构采用 4... 详细信息

介绍了国外摆式列车发展的基本概况 ,根据我国线路特点 ,提出了一种能满足我国铁路进一步提速的高速摆式客车转向架方案。文中对转向架的结构方案及其特点进行了详细的分析和说明。高速摆式客车转向架采用一系柔性定位 ,倾摆机构采用 4摆杆机构加机电式作动器的模式是可行的。对倾摆机构的运动学关系进行了分析 ,确定了车体的倾摆运动规律及其响应的参数。

关键词：摆式客车转向架倾摆机构动力学性能结构特点运动规律数值仿真

Metabonomic analysis of hepatitis B virus-induced liver failure:identification of potential diagnostic biomarkers by fuzzy support vector machine

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2008年第6期9卷 474-481页

作者： Yong mao Xin huang Ke YU hai-bin QU Chang-xiao LIU Yi-yu CHENG Pharmaceutical lnformatics Institute College of Pharmaceutical Sciences Zhejiang University Hangzhou 310027 China Tianjin Pharmaceutical Research Institute National Key Lab Pharmacokinetics and Pharmacodynamics Tianjin 300193 China

Hepatitis B virus （HBV）-induced liver failure is an emergent liver disease leading to high mortality. The severity of liver failure may be reflected by the profile of some metabolites. This study assessed the potential of using metabolites as biomarkers for liver failure by identifying metabolites with good discriminative performance for its phenotype. The serum samples from 24 HBV-indueed liver failure patients and 23 healthy volunteers were collected and analyzed by gas chromatography-mass spectrometry （GC-MS） to generate metabolite profiles. The 24 patients were further grouped into two classes according to the severity of liver failure. Twenty-five eommensal peaks in all metabolite profiles were extracted, and the relative area values of these peaks were used as features for each sample. Three algorithms, F-test, k-nearest neighbor （KNN） and fuzzy support vector machine （FSVM） combined with exhaustive search （ES）, were employed to identify a subset of metabolites （biomarkers） that best predict liver failure. Based on the achieved experimental dataset, 93.62% predictive accuracy by 6 features was selected with FSVM-ES and three key metabolites, glyeerie acid, cis-aeonitie acid and citric acid, are identified as potential diagnostic biomarkers.

关键词： Metabolite profile analysis Potential diagnostic biomarker identification k-nearest neighbor (KNN) Fuzzy supportvector machine (FSVM) Exhaustive search (ES) Gas chromatography-mass spectrometry (GC-MS) Hepatitis B virus (HBV)-induced liver failure

Changes in groundwater levels and the response of natural vegetation to transfer of water to the lower reaches of the Tarim River

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Journal of Environmental Sciences 2007年第10期19卷 1199-1207页

作者： XU hai-liang YE mao LI Ji-mei Xinfiang Institute of Ecology and Geography Research Chinese Academic of Science Urumqi 830011 China School of Geography Sciences and Touristy Xinfiang Normal University Urumqi 830054 China

Restoration and reconstruction of the degraded Tarim River ecosystem is an important challenge. A goal of an ecological water conveyance project is to protect and restore the natural vegetation in the lower reaches of Tadm River by transferring water from Bosten Lake, through the river channel, to the lower reaches. This study describes the changes in groundwater depth during the water transfer and the respondence of riparian vegetation to alterations in groundwater levels. The results indicate that groundwater depth along the Tarim River channel has a significant spatial-temporal component. Groundwater levels closest to the river channel show the most immediate and pronounced changes as a response to water transfer while those further away respond more slowly, although the observed change appears to be longer in duration. With a rise in the groundwater level, natural vegetation responded with higher growth rates, biomass and biodiversity. These favorable changes show that it is feasible to protect and restore the degraded natural vegetation by raising the groundwater depth. Plant communities are likely to reflect the hysteresis phenomenon, requiting higher water levels to initiate and stimulate desired growth than what may be needed to maintain the plant community. Because different species have different ecologies, including different root depths and densities and water needs, their response to increasing water availability will be spatially and temporally heterogenous. The response of vegetation is also influenced by microtopography and watering style. This paper discusses strategies for the protection and restoration of the degraded vegetation in the lower reaches of the Tarim River and provides information to complement ongoing theoretical research into ecological restoration in add or semi-arid ecosystems.

关键词： the lower reaches of Tarim River ecological watering conveyance groundwater depth ecological response natural vegetation

Expanding horizons in overcoming therapeutic resistance in castration-resistant prostate cancer:targeting the androgen receptor-regulated tumor immune microenvironment

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Cancer Biology & Medicine 2023年第8期20卷 568-574页

作者： Bisheng Cheng hai huang Department of Urology Sun Yat-sen Memorial HospitalSun Yat-sen UniversityGuangzhou 510120China

Castration-resistant prostate cancer(CRPC)poses a major treatment challenge,because disease progression occurs despite androgen deprivation therapy(ADT)*** therapeutic resistance in CRPC remains a critical unmet need in clinical *** androgen receptor(AR)signaling pathway plays a critical role in prostate cancer development and progression,and is also involved in regulating the tumor immune microenvironment(TIME).

关键词： therapeutic cancer resistance

Structural optimization for multiple structure cases and multiple payload cases with a two-level multipoint approximation method

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Chinese Journal of Aeronautics 2016年第5期29卷 1273-1284页

作者： An haichao Chen Shenyan huang hai School of Astronautics Beihang University

This paper is to address structural optimization problems where multiple structure cases or multiple payload cases can be considered simultaneously. Both types of optimization problems involve multiple finite element models at each iteration step, which draws high demands in opti- mization methods. Considering the common characteristic for these two types of problems, which is that the design domain keeps the same no matter what the structure cases or payload cases are, both problems can be formulated into the unified expressions. A two-level multipoint approxima- tion （TMA） method is firstly improved with the use of analytical sensitivity analysis for structural mass, and then this improved method is utilized to tackle these two types of problems. Based on the commercial finite element software ***/Nastran, an optimization system for multiple structure cases and multiple payload cases is developed. Numerical examples are conducted to verify its feasibility and efficiency, and the necessity for the simultaneous optimizations of multiple structure cases and multiple payload cases are illustrated as well.

关键词： Multipoint approximation Multiple payload cases Multiple structure cases Sensitivity analysis Structural optimization

Location optimization of multiple distribution centers under fuzzy environment

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2012年第10期13卷 782-798页

作者： Yong WANG Xiao-lei MA Yin-hai WANG hai-jun mao Yong ZHANG School of Transportation Southeast UniversiO Nanjing 210096 China Department of Civil and Environmental Engineering UniversiO of Washington Seattle WA 98195-2700 USA

Locating distribution centers optimally is a crucial and systematic task for *** located distribution centers can significantly improve the logistics system's efficiency and reduce its operational ***,it is not an easy task to optimize distribution center locations and previous studies focused primarily on location optimization of a single distribution *** growing logistics demands,multiple distribution centers become necessary to meet customers' requirements,but few studies have tackled the multiple distribution center locations(MDCLs) *** paper presents a comprehensive algorithm to address the MDCLs *** integration and clustering approach using the improved axiomatic fuzzy set(AFS) theory is developed for location clustering based on multiple hierarchical evaluation ***,technique for order preference by similarity to ideal solution(TOPSIS) is applied for evaluating and selecting the best candidate for each *** analysis is also conducted to assess the influence of each criterion in the location planning decision *** from a case study in Guiyang,China,reveals that the proposed approach developed in this study outperforms other similar algorithms for MDCLs *** new method may easily be extended to address location planning of other types of facilities,including hospitals,fire stations and schools.

关键词： Multiple distribution centers Location selection Clustering algorithm Axiomatic fuzzy set(AFS) Technique for order preference by similarity to ideal solution(TOPSIS)