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Numerical Study on the Impact of Ground Heating and Ambient Wind Speed on Flow Fields in Street Canyons

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Advances in Atmospheric Sciences 2012年第6期29卷 1227-1237页

作者：李磊杨琳张立杰江崟 Shenzhen National Climate Observatory Meteorological Bureau of Shenzhen Municipality Shenzhen Meteorological Service Center Meteorological Bureau of Shenzhen Municipality

The impact of ground heating on flow fields in street canyons under different ambient wind speed conditions was studied based on numerical methods. A series of numerical tests were performed, and three factors including height-to-width （H/W） ratio, ambient wind speed and ground heating intensity were taken into account. Three types of street canyon with H/W ratios of 0.5, 1.0 and 2.0, respectively, were used in the simulation and seven speed values ranging from 0.0 to 3.0 m s-1 were set for the ambient wind speed. The ground heating intensity, which was defined as the difference b-ween the ground temperature and air temperature, ranged from 10 to 40 K with an increase of 10 K in the tests. The results showed that under calm conditions, ground heating could induce circulation with a wind speed of around 1.0 m s-i, which is enough to disperse pollutants in a street canyon. It was also found that an ambient wind speed threshold may exist for street canyons with a fixed H/W ratio. When ambient wind speed was lower than the threshold identified in this study, the impact of the thermal effect on the flow field was obvious, and there existed a multi-vortex flow pattern in the street canyon. When the ambient wind speed was higher than the threshold, the circulation pattern was basically determined by dynamic effects. The tests on the impact of heating intensity showed that a higher ground heating intensity could strengthen the vortical flow within the street canyon, which would help improve pollutant diffusion capability in street canyons.

关键词： street canyon thermal effect ambient wind ground heating intensity computational fluid dynamics (CFD)

MODEliNG AND IMPLEMENTATION OF A DISTRIBUTED SHOP FLOOR MANAGEMENT AND CONTROL SYSTEM

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Chinese Journal of Mechanical Engineering 2002年第3期15卷 213-217页

作者： liu Shiping Rao Yunqing zhang jie li PeigenSchool of Mechanical Science and Engineering, Huazhong University of Science and Technology,Wuhan 430074, China School of Mechanical Science and Engineering Huazhong University of Science and Technology Wuhan 430074

Adopting distributed control architecture is the important developmentdirection for shop floor management and control system, is also the requirement of making it agile,intelligent and concurrent. Some key problems in achieving distributed control architecture areresearched. An activity model of shop floor is presented as the requirement definition of theprototype system. The multi-agent based software architecture is constructed. How the core part inshop floor management and control system, production plan and scheduling is achieved. Thecooperation of different agents is illustrated. Finally, the implementation of the prototype systemis narrated.

关键词： Agent Shop floor management and control CIMS

Bupleurum polysaccharides ameliorated renal injury in diabetic mice associated with suppression of HMGB1-TLR4 signaling

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Chinese Journal of Natural Medicines 2019年第9期17卷 641-649页

作者： liU Zhen-Zhen WENG Hong-Bo zhang li-jie PAN ling-Yu SUN Wei CHEN Hai-Xia CHEN Mei-Yu ZENG Tao zhang Yun-Yi CHEN Dao-Feng li Hong Department of Pharmacology School of PharmacyFudan UniversityShanghai 201203China Department of Pharmacognosy School of PharmacyFudan UniversityShanghai 201203China Clinical trial institution Obstetrics and Gynecology Hospital of Fudan UniversityShanghai 201203China

Bupleurum polysaccharides(BPs)is isolated from Bupleurum smithii ***,a key traditional Chinese *** study was to investigate the effects of BPs on diabetic kidney *** two intraperitoneal injections of streptozotozin(STZ)100 mg·kg^–1,renal injury in diabetic mice was induced and BPs was orally administrated at dosages of 30 and 60 mg·kg^–1·d^–*** STZ injected mice developed renal function damage,renal inflammation and fibrosis known as diabetic kidney disease(DKD).BPs significantly reduced serum creatinine level and urinary albumin excretion rate,with the attenuated swelling of *** treatment obviously alleviated the pathological damage of renal *** progression of renal injury in BPs treated mice was inhibited with less expression of type IV collagen(Col IV),fibronectin(FN)andα-smooth muscle actin(α-SMA).The inhibition of inflammation in kidney was associated with the reduced level of tumor necrosis factor-α(TNF-α)and interleukin-6(IL-6).BPs administration suppressed the over-expression of toll like receptor 4(TLR4)and high-mobility group box 1(HMGB1)with lowered activity of nuclear factor kappa B(NF-κB)in renal tissue of diabetic *** administration of BPs effectively prevented the development of renal injury in diabetic *** study suggested that the protection provided by BPs might affect through the interruption of HMGB1-TLR4 pathway,leading to the inhibition of renal inflammation and fibrotic process.

关键词： Renal injury Bupleurum:High-mobility group box Toll-like receptor 4 Inflammation Renal fibrosis Polysaccharides

Successful Treatment with Rituximab in a Patient with Castleman＇s Disease Complicated by Systemic Lupus Erythematosus and Severe Autoimmune Thrombocytopenia

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Chinese Medical Journal 2015年第18期128卷 2551-2552页

作者： Lu zhang li Jiao Shu-jie Wang Department of Hematology Peking Union Medical College Hospital Chinese Academy of Medical Sciences Beijing 100730 China

To the Editor： A 44-year-old man with no remarkable past medical history, was admitted with I-month history of fever and lymphadenopathy. He also had night sweats, malaise. arthralgia, urine volume reduction, abdominal distention, and weight loss. Physical exainination revealed swollen lymph nodes in the neck, axillary fossae and inguinal grooves, palpable liver and spleen, shifting dullness and edema.

关键词：发热肝关节痛红斑狼疮系统性颈巨淋巴结增生脾紫癜血小板减少性特发性

Comparison of Headspace Solid-Phase Microextraction with Simultaneous Steam Distillation Extraction for the Analysis of the Volatile Constituents in Chinese Apricot

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Agricultural Sciences in China 2006年第11期5卷 879-884页

作者： CHEN Mei-xia CHEN Xue-sen WANG Xin-guo CI Zhi-juan liU Xiao-li HE Tian-ming zhang li-jie Weifang Vacational College Weifang 261041 P.R.China College of Horticultural Science and Engineering Shandong Agricultural University Taian 271018 P.R.China

Volatile constituents in fully mature fruits of apricot （Prunus armeniaca L.） cultivar Xinshiji were extracted using headspace solid-phase microextraction （HS-SPME） and simultaneous steam distillation extraction （SSDE） and then analyzed using capillary gas chromatography and gas chromatography-mass spectrometry. A total of 70 components were identified by HSSPME, including 20 esters, 19 hydrocarbons, 5 alcohols, 5 ketones, 4 acids, 4 lactones, 3 aldehydes, and 10 miscellaneous components, with the esters being the dominant constituent. On the basis of the odor unit values, it is believed that the following compounds probably contributed to the fresh apricot odor： hexyl acetate, β-ionone, butyl acetate, （E）-2-hexenal, linalool, limonene, γ-decalactone, and hexanal. A total of 49 components were also detected by SSDE, including 13 hydrocarbons, 9 alcohols, 7 aldehydes, 9 esters, 4 ketones, 4 lactones, 2 acids, and 1 miscellaneous component, of which the monoterpene alcohols were the dominant constituents. It could be judged from the odor unit values that the following compounds were the major contributors to boiled apricot aroma： β-ionone, linalool, hexyl acetate, γ-dodecalactone, γ- decalactone, （E）-2-hexenal, hexanal, γ-octalactone, phenylacetaldehyde, butyl acetate, limonene, α-terpineol, and δ-decalactone. The results show that HS-SPME is a simple, rapid, and solvent-free method, which is an alternative to the classical SSDE.

关键词： aroma volatile constituents apricot solid-phase microextraction simultaneous distillation-extraction

Effects of the extrusion parameters on microstructure,texture and room temperature mechanical properties of extruded Mg-2.49Nd-1.82Gd-0.2Zn-0.2Zr alloy

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International Journal of Minerals,Metallurgy and Materials 2025年第1期32卷 136-146页

作者： Chenjin zhang Guangyu Yang Lei Xiao Zhiyong Kan Jing Guo Qiang li Wanqi jie State Key Laboratory of Solidification Processing Northwestern Polytechnical UniversityXi’an 710072China College of Materials Science and Engineering Fuzhou UniversityFuzhou 350108China College of Chemistry and Environmental Science Qujing Normal UniversityQujing 655011China

Microstructure,texture,and mechanical properties of the extruded Mg-2.49Nd-1.82Gd-0.2Zn-0.2Zr alloy were investigated at different extrusion temperatures(260 and 320℃),extrusion ratios(10:1,15:1,and 30:1),and extrusion speeds(3 and 6 mm/s).The experimental results exhibited that the grain sizes after extrusion were much finer than that of the homogenized alloy,and the second phase showed streamline distribution along the extrusion direction(ED).With extrusion temperature increased from 260 to 320℃,the microstructure,texture,and mechanical properties of alloys changed *** dynamic recrystallization(DRX)degree and grain sizes enhanced as the extrusion ratio increased from 10:1 to 30:1,and the strength gradually decreased but elongation(EL)*** the extrusion speed increased from 3 to 6 mm/s,the grain sizes and DRX degree increased significantly,and the samples presented the typical-rare-earth(RE)*** alloy extruded at 260℃ with extrusion ratio of 10:1 and extrusion speed of 3 mm/s showed the tensile yield strength(TYS)of 213 MPa and EL of 30.6%.After quantitatively analyzing the contribution of strengthening mechanisms,it was found that the grain boundary strengthening and dislocation strengthening played major roles among strengthening *** results provide some guidelines for enlarging the industrial application of extruded Mg-RE alloy.

关键词： Mg-rare earth alloys extrusion temperature extrusion ratio extrusion speed strengthening mechanisms

Gamma-glutamyl transferase 5 overexpression in cerebrovascular endothelial cells improves brain pathology,cognition,and behavior in APP/PS1 mice

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Neural Regeneration Research 2025年第2期20卷 533-547页

作者： Yanli zhang Tian li jie Miao Zhina zhang Mingxuan Yang Zhuoran Wang Bo Yang Jiawei zhang Haiting li Qiang Su Junhong Guo Department of Neurology First Hospital of Shanxi Medical UniversityTaiyuanShanxi ProvinceChina Department of Neurology Sixth Hospital of Shanxi Medical University(General Hospital of Tisco)TaiyuanShanxi ProvinceChina Department of Physiology Key Laboratory of Cellular PhysiologyMinistry of EducationShanxi Medical UniversityTaiyuanShanxi ProvinceChina Department of Hernia and Abdominal Wall Surgery Shanxi Bethune HospitalShanxi Academy of Medical SciencesTongji Shanxi HospitalThird Hospital of Shanxi Medical UniversityTaiyuanShanxi ProvinceChina Department of Laboratory Medicine of Fenyang College Shanxi Medical UniversityFenyangShanxi ProvinceChina

In patients with Alzheimer’s disease,gamma-glutamyl transferase 5(GGT5)expression has been observed to be downregulated in cerebrovascular endothelial ***,the functional role of GGT5 in the development of Alzheimer’s disease remains *** study aimed to explore the effect of GGT5 on cognitive function and brain pathology in an APP/PS1 mouse model of Alzheimer’s disease,as well as the underlying *** observed a significant reduction in GGT5 expression in two in vitro models of Alzheimer’s disease(Aβ_(1-42)-treated hCMEC/D3 and bEnd.3 cells),as well as in the APP/PS1 mouse ***,injection of APP/PS1 mice with an adeno-associated virus encoding GGT5 enhanced hippocampal synaptic plasticity and mitigated cognitive ***,increasing GGT5 expression in cerebrovascular endothelial cells reduced levels of both soluble and insoluble amyloid-βin the brains of APP/PS1 *** effect may be attributable to inhibition of the expression ofβ-site APP cleaving enzyme 1,which is mediated by nuclear factor-kappa *** findings demonstrate that GGT5 expression in cerebrovascular endothelial cells is inversely associated with Alzheimer’s disease pathogenesis,and that GGT5 upregulation mitigates cognitive deficits in APP/PS1 *** findings suggest that GGT5 expression in cerebrovascular endothelial cells is a potential therapeutic target and biomarker for Alzheimer’s disease.

关键词： Alzheimer’s disease amyloid-β APP/PS1 mice cerebrovascular endothelial cells cognitive deficits gamma-glutamyl transferase 5 neurovascular unit nuclear factor‐kappa B synaptic plasticity β-site APP cleaving enzyme 1

Force Modeling for Ultrasonic-assisted Wire Saw Cutting SiC Monocryatal Wafers

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International Journal of Plant Engineering and Management 2011年第4期16卷 225-236页

作者： zhang jie li Shujuan liu Yong The School of Mechanical and Instrument Engineering of Xi＇an University of Technology Xi＇an 710048 P. R. China

The advantages, such as a small cutting force, narrow kerf and little material waste make wire saw cut- ting suitable for machining precious materials like SiC, Si monocrystal and a variety of gem. As regards wire saw cutting fo wafer, however, in traditional wire saw cutting process, the cutting efficiency is low, the wear of wire saw is badly, the surface roughness of wafer is poor etc, which have a seriously impact on the cutting process stability and the use of wafers. Ultrasonic-assisted machining method is very suitable for processing a variety of non-conduc- tive hard and brittle materials, glass, ceramics, quartz, silicon, precious stones and diamonds, etc. In this paper, the force model of ultrusonic-assisted wire saw cutting of SiC monocrystal wafer, based on the kinematic and experi- mental analysis were established. The single factor and orthogonal experimental scheme for different processing pa- rameters such as wire saw speed, part rotation speed of and part feed rate, were carried out in traditional wire saw and ultrasonic-assisted wire saw cutting process. The multiple linear regression method is used to establish the static model among the cutting force, processing parameters and ultrasonic vibration parameters, and the model signifi- cance is verified. The results show, as regards ultrasonic-assisted wire saw cutting of SiC monicrystal wafer, both the tangential and normal cutting forces can reduce about 24. 5%-36% and 36. 6%-40%.

关键词： wire saw ultrasonic-assisted cutting force modeling

A Contrastive Study of English and Chinese Taboos in Cross-cultural Communication

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科技视界 2017年第4期 262-263页

作者： liU Yang zhang li-jie Northeastern Forestry University Harbin Heilongjiang 150040China

A commonly cultural phenomenon in the human history is taboo, which is a strong social prohibition related to any area of human society. Different social and cultural backgrounds will produce different taboos. Lacking the knowledge of social customs may cause conflicts in crosscultural communication. So it is necessary to know more about taboos. This paper analyzes the the cultural similarities and difference between Chinese and English taboos in a contrastive way in cross-cultural communication and stresses the importance of?understanding and mastering taboos, so that they can reduce the inter-communicative barriers and mistakes and improve their communicative ability.

关键词：英语学习学习方法阅读知识阅读材料