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Insights into the rheological modeling of semi-solid metals:Theoretical and simulation study

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Journal of Materials Science & Technology 2022年第5期100卷 182-192页

作者： Zhen Ma Huarui Zhang Hanwei Fu Yanzhao Yang Jianji Wang ming du Hu Zhang School of Materials Science and Engineering Beihang UniversityBeijing 100191China FAW-VOLKSWAGEN Automobile Co. LtdQingdao 266000China Ningbo Institute of Technology Beihang UniversityNingbo 315832China

The power law model is the most widely used model for the rheological behavior of semi-solid metals(SSMs)in the numerical simulation of semi-solid ***,it is still not known why the anomalous negative flow exponent exists in the power law model for SSMs and its influence on the *** this research,the rheological behavior of semi-solid Al-7Si-0.3Mg aluminum alloy is experimentally studied followed by *** power law model fitting results show flow curves deviate from the experimental data and negative flow exponents,which are physically nonsensical and inapplicable to the simulation of SSMs flow proved by hydrodynamic *** drawback of the power law model stems from neglecting the yield stress of *** contrast,the model referring Herschel-Bulkley(HB)theory which takes yield stress into consideration has reasonable flow exponent and yields good agreement between the fitting and experimental ***,the simulation of die filling process is conducted,suggesting that the power law model over-optimistically predicts the tendency of blistering and misrun defects at low temperature and high filling velocity during semi-solid processing.

关键词： Semi-solid metal Rheological behavior Modeling Simulation Aluminum alloys

Filiform needle acupuncture for allergic rhinitis:A systematic review and meta-analysis

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Journal of Integrative Medicine 2022年第6期20卷 497-513页

作者： Shi-hao du Wei Guo Chao Yang Sheng Chen Sheng-nan Guo Shuo du Zhong-ming du Yu-tong Fei Ji-ping Zhao Dongzhimen Hospital Beijing University of Chinese MedicineBeijing100700China Institute of Acupuncture and Moxibustion China Academy of Chinese Medical SciencesBeijing100700China Centre for Evidence-Based Chinese Medicine Beijing University of Chinese Medicine100029BeijingChina

Background:Filiform needle acupuncture(FNA),the most classical and widely applied acupuncture method based on traditional Chinese medicine theory,has shown a promising effect in the treatment of allergic rhinitis(AR).Objective:To evaluate the efficacy,safety,cost-effectiveness,and patient preference of FNA in the treatment of AR by comparing FNA with sham acupuncture,no treatment,and conventional *** strategy:Eight electronic databases were systematically searched from inception to October 14,*** studies were acquired from clinical trial registration platforms and reference *** criteria:Randomized controlled trials were included if they compared FNA with either sham acupuncture,no treatment or conventional medication for *** extraction and analysis:Two researchers extracted data independently of each other using a predesigned data acquisition form,and results were cross-checked after *** primary outcome was symptom score(Total Nasal Symptom Score or Visual Analogue Scale),and the secondary outcomes were the AR control questionnaire,quality of life(QoL)score(Different versions of Rhinoconjunctivitis Quality of Life Questionnaire),medication score(use of rescue medication),mental health score,total IgE,adverse event rate,clinical economic indicators,and patient satisfaction *** mean difference(SMD)or mean difference(MD)with 95% confidence interval was used to calculate the effect size for continuous data,while risk ratio with 95%CI was used for dichotomous ***:Thirty studies were included in this *** with sham acupuncture,FNA significantly reduced the symptom score(SMD:-0.29[-0.43,-0.15]),AR’s impact on QoL(SMD:-0.23[-0.37,-0.08])and medication score(SMD:-0.3[-0.49,-0.11]).Compared with no treatment,FNA dramatically reduced the symptom score(SMD:-0.8[-1.2,-0.39])and AR’s impact on QoL(SMD:-0.82[-1.13,-0.52]).There were no increased rates of adverse events with FNA compared to sham

关键词： Allergic rhinitis Filiform needle acupuncture Systematic review Meta-analysis

THz Output Improvement in a Photomixer with a Resonant-Cavity-Enhanced Structure

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Chinese Physics Letters 2012年第4期29卷 79-81页

作者： du ming-Di SUN Jun-Qiang CHENG Wen-Long Wuhan National Laboratory for Optoelectronics School of Optoelectronic Science and EngineeringHuazhong University of Science and TechnologyWuhan 430074

We carry out a detailed theoretical study on THz coherent generation in an LTG-GaAs photomixer with a resonant-cavity-enhanced (RCE) *** the structure,an improvement in THz output can be achieved by increasing the quantum *** optimized structure parameters,the maximum quantum efficiency of the RCE photomixer is 93%,which is 2.82 times higher than that of the case without an RCE *** corresponding THz output ratio of the two structures is found to be about eight in the whole range of the lower frequency at the same incident optical power.

关键词： mixer RCE quantum

Determination of L-phenylalanine by cucurbit[7]uril sensitized fluorescence quenching method

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Chinese Chemical Letters 2011年第7期22卷 851-854页

作者： Chang Feng Li Li ming du Hao Wu Ying Xia Chang Analytical and Testing Center Shanxi Normal University Linfen 041004 China School of Chemistry and Materials Science Shanxi Normal University Linfen 041004 China

The determination method of L-phenylalartine （LPA） by fluorescence quenching was developed. The assay was based on the combination of the cucurbit[7]uril （CB [7]） with palmatine hydrochloride （PAL） reaction. In the presence of CB [7], the fluorescence of PAL was quenched by LPA which can be employed to detect LPA. Under the optimal conditions, a linear range 3.63 ×10^-8- 9.68 ×10^-6 mol/L and a detection limit 1.27 ×10^-8 mol/L of LPA were obtained. The relative standard deviation （R.S.D） was 1.8% obtained from a series of 11 standards each containing 6.05 ×10^-6 mol/L of LPA. This paper also discusses the mechanism of fluorescence indicator probe.

关键词： L-phenylalanine Palmatine hydrochloride Cucurbituril Fluorescent probe

Study on the inclusion interaction of methylated-β-cyclodextrins with albendazole by spectrofluorimetry and its application

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Chinese Chemical Letters 2008年第8期19卷 951-954页

作者： Guo Yan Zhao Hao Wu Sheng Li Dong Li ming du Analytical and Testing Center Shanxi Normal University Linfen 041004 China

The inclusion interaction between three types of methylated-β-cyclodextrins （Me-β-CDs） and albendazole （ABZ） was studied by spectrofluorimetry. The result showed that Me-β-CDs reacted with ABZ to form an inclusion complex, 1： 1 stoichiometry for Me- β-CDs-ABZ complex was established and its association constant have been determined from fluorescence data by Benesi- Hildebrand＇s method （double reciprocal plots）. It was noted that 2,6-DM-β-CD exhibited stronger binding ability than other Me-β- CDs. Based on the significant enhancement of fluorescence intensity of inclusion complex, a simple and highly sensitive fluorimetric method is proposed for the determination of ABZ in the presence of 2,6-DM-β-CD. The proposed method was successfully applied to the determination of ABZ in tablets and human urine.

关键词： Methylated-β-cyclodextrins Albendazole Spectrofluorimetry

基于500kV超高压线受限空间地铁明挖车站施工关键技术及风险控制

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建筑机械 2024年第5期 127-130,136页

作者：包世波杜明阳魏传光中国交通建设股份有限公司轨道交通分公司北京101399

本文针对重庆轨道交通15号线大学城中路站下穿500kV超高压线超低净空条件下轨道交通地铁明挖车站施工关键技术与安全风险防控措施进行研究和分析,通过对500kV超高压线施做安全防护隔离网、优化设备选型、施工组织、安全风险管控等措施,... 详细信息

本文针对重庆轨道交通15号线大学城中路站下穿500kV超高压线超低净空条件下轨道交通地铁明挖车站施工关键技术与安全风险防控措施进行研究和分析,通过对500kV超高压线施做安全防护隔离网、优化设备选型、施工组织、安全风险管控等措施,实现在500kV超高压线下地铁安全施工目的,为类似工程提供借鉴。

关键词：超高压线受限空间防护隔离网设备选型安全风险管控

Physisorption of Hydrogen in A, X and ZSM-5 Types of Zeolites at Moderately High Pressures

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Chinese Journal of Chemical Physics 2006年第5期19卷 457-462页

作者： Xiao-ming du Er-dong Wu Shenyang National Laboratory for Materials Sciences Institute of Metal Research Chinese Academy of Science Shenyang 110016 China

The hydrogen adsorption properties and uptake capacities of the A, X and ZSM-5 types of zeolites were investigated at temperatures of 77, 195 and 293 K and pressures up to 7 MPa, using a conventional volumetric adsorption apparatus. All hydrogen adsorption isotherms were basically type Ⅰ, but the maximum in isotherm, a unique feature of supereritical adsorption, was observed at high pressures of 2-5 MPa at 77 K. The isosteric heats of adsorption were determined from the isotherms and the factors that influence their variations were discussed. Different types of zeolites exhibited remarkably different hydrogen uptake, based on both the framework structure and the nature of the cations present. The highest gravimetrie storage capacity of 2.55wt% was obtained for NaX-type zeolite at 4 MPa and 77 K. In CaA, NaX and ZSM-5 types of zeolites, hydrogen uptakes were proportional to the specific surface areas, which were associated with the available void volumes of the zeolites. A threshold in hydrogen adsorption observed in NaA and KA was attributed to a pore blocking effect by large cations in KA. A ratio of the kinetic diameter of adsorbate to the effective opening diameter of zeolite was used to judge the blocking effect for physisorption.

关键词： Zeolite Hydrogen storage Hydrogen adsorption Adsorption isotherm

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垦稻系列水稻品种的发芽特性研究

现代农业科技 2024年第3期 13-16页

作者：周燕慕永红杜明王萌那永光黑龙江省农垦科学院水稻研究所黑龙江佳木斯154000

为明确垦稻系列品种的发芽特性,选取黑龙江省农垦科学院水稻研究所选育并已大面积推广种植的7个品种进行发芽试验。结果表明,在确定参试种子能发芽的前提下,参试的7个品种在发芽速度、出根速度、芽长、根数、根形等方面均有较大差异,充... 详细信息

为明确垦稻系列品种的发芽特性,选取黑龙江省农垦科学院水稻研究所选育并已大面积推广种植的7个品种进行发芽试验。结果表明,在确定参试种子能发芽的前提下,参试的7个品种在发芽速度、出根速度、芽长、根数、根形等方面均有较大差异,充分体现了不同品种的发芽特性不同,如空育131、垦稻1918等发芽出根较慢,垦研017、垦稻1726等发芽快、出根快,垦稻1725等根系较短、出根较慢。在试验过程中,7个品种的发芽速度各不相同。在实际生产中,应根据不同品种的萌发特性,适度改变育苗方式进行生产。

关键词：水稻垦稻系列品种发芽特性发芽势发芽率

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温针灸八髎穴与天枢穴联合养血滋阴汤对老年人功能性便秘临床症状和血清胃肠激素水平的影响

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陕西中医 2024年第6期45卷 841-845页

作者：杜明张若琳戴秋红郝冉秦皇岛市中医医院脾胃科河北秦皇岛066000 哈尔滨医科大学第一附属医院神经内科黑龙江哈尔滨150000

目的:探究温针灸八髎穴与天枢穴联合养血滋阴汤对老年功能性便秘(FC)临床症状和血清胃肠激素水平的影响。方法:选取108例老年FC患者,随机分为研究组和对照组各54例。对照组服用枸橼酸莫沙必利片,研究组在对照组的基础上采用温针灸八髎... 详细信息

目的:探究温针灸八髎穴与天枢穴联合养血滋阴汤对老年功能性便秘(FC)临床症状和血清胃肠激素水平的影响。方法:选取108例老年FC患者,随机分为研究组和对照组各54例。对照组服用枸橼酸莫沙必利片,研究组在对照组的基础上采用温针灸八髎穴与天枢穴联合养血滋阴汤进行治疗。评估两组治疗后的疗效,治疗前后评估两组患者的排便情况(排便不尽感评分、排便费力评分、排便不成功次数)、便秘严重程度和中医证候评分,测定两组患者治疗前后的胃肠激素水平[血清胃动素(MTL)、血管活性肠肽(VIP)、胃泌素(GAS)],肛肠动力学指标[肛管静息压(ARP)、直肠静息压(RRP)],并观察不良反应。结果:治疗后,研究组的治疗总有效率高于对照组(P0.05)。结论:温针灸八髎穴与天枢穴联合养血滋阴汤治疗老年FC能有效提升临床疗效,改善患者的便秘情况,促进胃肠激素分泌,改善肛肠动力学指标,且安全性良好。

关键词：功能性便秘老年温针灸八髎穴天枢穴养血滋阴汤胃肠激素水平