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可调汽蚀管式调节阀的仿真与试验研究

阀门 2024年第8期 969-976页

作者：何海涛朱崇涛胡锐陈苗赵承卓罗庶胡兆华航天科工火箭技术有限公司湖北武汉430040

可调汽蚀管式调节阀采用汽蚀文氏管原理,能有效实现推进剂流量的大范围调节,是液体火箭发动机推力调节的关键部件。本文针对不同锥度的两种阀杆,通过仿真和试验对其调节性能进行了分析研究,获得了阀杆不同行程下的有效流通面积和相对压... 详细信息

可调汽蚀管式调节阀采用汽蚀文氏管原理,能有效实现推进剂流量的大范围调节,是液体火箭发动机推力调节的关键部件。本文针对不同锥度的两种阀杆,通过仿真和试验对其调节性能进行了分析研究,获得了阀杆不同行程下的有效流通面积和相对压力损失。结果表明:两种阀杆的仿真结果和试验数据吻合较好,均能满足流量线性调节的要求,阀杆B的流量可调范围更大,但在满足流量调节范围的要求下,阀杆A的调节精度会更高。两种阀杆的相对压力损失试验结果相差不大,但阀杆A仿真得到的相对压力损失更大。通过仿真结果和试验数据的对比,验证了仿真模型的正确性,为相关设计提供重要参考。

关键词：调节阀火箭发动机变推力汽蚀仿真与试验研究

Uptake,transport and distribution of molybdenum in two oilseed rape (Brassica napus L.) cultivars under different nitrate/ammonium ratios

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2017年第6期18卷 512-521页

作者： Shi-yu QIN Xue-cheng SUN Cheng-xiao hu Qi-ling TAN Xiao-hu zhao Microelement Research Center Huazhong Agricultural UniversityWuhan 430070China hubei Provincial Engineering Laboratory for New-Type Fertilizer College of Resources and EnvironmentHuazhong Agricultural UniversityWuhan 430070China MOA Key Laboratory of Arable Land Conservation(Middle and Lower Reaches of Yangtze River) Wuhan 430070China

Objectives：To investigate the effects of different nitrate sources on the uptake,transport,and distribution of molybdenum（Mo）between two oilseed rape（Brassica napus L.）cultivars,L0917 and ***：A hydroponic culture experiment was conducted with four nitrate/ammonium（NO3^-：NH4^＋）ratios（14：1,9：6,7.5：7.5,and 1：14）at a constant nitrogen concentration of 15 mmol/*** examined Mo concentrations in roots,shoots,xylem and phloem sap,and subcellular fractions of leaves to contrast Mo uptake,transport,and subcellular distribution between ZS11and ***：Both the cultivars showed maximum biomass and Mo accumulation at the 7.5：7.5 ratio of NO3^-：NH4^＋ while those were decreased by the 14：1 and 1：14 ***,the percentages of root Mo（14.8%and 15.0%for L0917 and ZS11,respectively）were low under the 7.5：7.5 treatment,suggesting that the equal NO3^-：NH4^＋ratio promoted Mo transportation from root to *** xylem sap Mo concentration and phloem sap Mo accumulation of L0917 were lower than those of ZS11 under the 1：14 treatment,which suggests that higher NO3^-：NH4^＋ratio was more beneficial for *** the contrary,a lower NO3^-：NH4^＋ratio was more beneficial for ZS11 to transport and remobilize ***,the Mo concentrations of both the cultivars’leaf organelles were increased but the Mo accumulations of the cell wall and soluble fraction were reduced significantly under the 14：1 treatment,meaning that more Mo was accumulated in organelles under the highest NO3^-：NH4^＋***：This investigation demonstrated that the capacities of Mo absorption,transportation and subcellular distribution play an important role in genotype-dependent differences in Mo accumulation under low or high NO3^-：NH4^＋ratio conditions.

关键词： Brassica napus L Nitrogen source Transport Subcellular distribution Xylem Phloem

Narrow-bandgap Nb_2O_5 nanowires with enclosed pores as high-performance photocatalyst

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Science China Materials 2019年第2期62卷 203-210页

作者： Ying Zhang hu zhao Xiaofei zhao Jiannan Lin Na Li Ziyang huo Zifeng Yan Miao Zhang Shi hu State Key Laboratory for Heavy Oil Processing PetroChina Key Laboratory of Catalysis China University of PetroleumQingdao Department of Chemistry School of Science Tianjin Key Laboratory of Molecular Optoelectronic Science Tianjin University Queensland Micro- and Nanotechnology Centre Griffith University Chemical Science Division Department of Chemistry University of CaliforniaBerkeley

Porous niobium oxide nanowires synthesized via a solvothermal method exhibited decreased bandgap,en- hanced light absorption and reduced charge-recombination *** porous Nb2O5 nanowires showed increased performance for the photocatalytic H2 evolution and photo- degradation of rhodamine B,as compared to their solid counterparts,which could be ascribed to the peculiar porous nanostructure.

关键词： niobium oxide nanowires photocatalysis

Molecule functionalization to facilitate electrocatalytic oxygen reduction on graphdiyne

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Journal of Energy Chemistry 2022年第2期31卷 141-148页

作者： huiying Yao Yasong zhao Nailiang Yang Wei Hao hu zhao Shuzhou Li Jia Zhu Lin Shen Weihai Fang College of Chemistry Key Laboratory of Theoretical&Computational Photochemistry of Ministry of EducationBeijing Normal UniversityBeijing 100875China State Key Laboratory of Biochemical Engineering Institute of Process EngineeringChinese Academy of SciencesBeijing 100190China School of Materials Science and Engineering Nanyang Technological University50 Nanyang Avenue639798Singapore Department of Physics Beijing Normal UniversityBeijing 100875China Laboratory of Theoretical and Computational Nanoscience CAS Center for Excellence in NanoscienceNational Center for Nanoscience and TechnologyChinese Academy of SciencesBeijing 100190China

Chemical doping is verified to be a promising strategy to regulate local electron distribution and further promote the poor intrinsic catalytic activity of ***,the current doping approach still faces problems such as precise doping for creating active sites and the destruction of graphdiyne skeleton calling for high ***,we achieved charge redistribution on graphdiyne surface through molecule functionalization.A p-type molecule–F4 TCNQ(2,3,5,6-tetrafluoro-7,7,8,8-tetracyanoquinodime thane)was introduced and the site-defined functionalization was *** calculations showed that the charge transfer ability is improved and graphdiyne becomes positively *** oxygen reduction electrocatalysis was conducted as a proof of principle,where the electronic states of sp hybridized C active site was tuned toward favorable reaction intermediates’*** work from both theoretical prediction and experimental validation,found that molecule functionalization is effective to promote the electrocatalytic oxygen reduction,which creates new possibilities for graphdiyne’s applications in different electrochemical reactions.

关键词： Graphdiyne F4TCNQ Density functional calculations Electronic structure Oxygen reduction reaction

钬激光解剖性剜除术治疗大体积良性前列腺增生的临床研究

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中外医疗 2024年第11期43卷 33-36页

作者：刘一庆温开伦赵虎灌云县人医院泌尿外科江苏连云港222200

目的探究应用钬激光解剖性剜除术治疗大体积良性前列腺增生疾病中采取临床效果。方法随机选取灌云县人民医院于2022年7月—2023年11月收治的大体积良性前列腺增生患者130例为研究对象,采用随机数表法进行分组,对照组进行前列腺电切术,... 详细信息

目的探究应用钬激光解剖性剜除术治疗大体积良性前列腺增生疾病中采取临床效果。方法随机选取灌云县人民医院于2022年7月—2023年11月收治的大体积良性前列腺增生患者130例为研究对象,采用随机数表法进行分组,对照组进行前列腺电切术,观察组进行钬激光解剖性剜除术,每组65例。对比尿流动力学指标、围术期指标、国际前列腺症状评分(International Prostate Symptom Score,IPSS)、并发症。结果与对照组残余尿量(24.80±5.90)mL比较,观察组(20.38±5.42)mL更低,差异有统计学意义(t=4.448,P<0.05)。观察组的最大尿流率高于对照组,差异有统计学意义(P<0.05)。与对照组相比,观察组的术中出血量更少,术中切除增生组织量更多,手术时间、膀胱冲洗时间、导尿管留置时间、住院时间均更短,IPSS评分和并发症发生率更低,差异有统计学意义(P均<0.05)。结论针对大体积良性前列腺增生患者,实施钬激光解剖性剜除术,能够改善尿流动力学指标,出血量少,切除组织量更多,改善临床症状,并发症少。

关键词：钬激光解剖性剜除术大体积良性前列腺增生尿流动力学并发症

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A long journey： report of a case with pancreatic abscess extending to the groin

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Chinese Medical Journal 2010年第22期123卷 3362-3363页

作者： LU hui-min ZHANG zhao-da hu Wei-ming Department of Hepato-bilio-pancreatic surgery West China Hospital Sichuan University Chengdu Sichuan 610041 China

Acute pancreatitis is an inflammatory process with .variable involvement of regional tissue, remote organ systems, or both. Various complications of pancreatitis are common, including intra- or extrapancreatic fluid collections and development of a pancreatic pseudocyst or abscess, or even pancreatic tissue necrosis. Infected necrosis involves diffuse bacterial inflammation of necrotic pancreatic and peripancreatic tissue without significant pus collection. In contrast, a pancreatic abscess is a circumscribed collection of pus, usually in proximity to the pancreas, that is positive for bacteria, bounded by adjacent tissue and organs and has minimal amounts of associated necrosis.

关键词： pancreatic abscess groin

经脐单孔腹腔镜联合体外囊肿剥除治疗卵巢巨大囊肿及盆腔巨大囊性包块的效果及安全性

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临床医学 2024年第3期44卷 1-4页

作者：方莹袁博王利君赵虎郑州大学第二附属医院妇科 450014

目的探讨经脐单孔腹腔镜联合体外囊肿剥除治疗卵巢巨大囊肿及盆腔巨大囊性包块(长径>10 cm)的安全性和有效性。方法选择2019年1月至2022年1月在郑州大学第二附属医院就诊的84例卵巢巨大囊肿及盆腔巨大囊性包块患者为研究对象,包块长径10... 详细信息

目的探讨经脐单孔腹腔镜联合体外囊肿剥除治疗卵巢巨大囊肿及盆腔巨大囊性包块(长径>10 cm)的安全性和有效性。方法选择2019年1月至2022年1月在郑州大学第二附属医院就诊的84例卵巢巨大囊肿及盆腔巨大囊性包块患者为研究对象,包块长径10~32 cm。按照随机数字表法分为观察组与对照组,每组42例。观察组行经脐单孔腹腔镜联合体外囊肿剥除术,对照组行多孔腹腔镜囊肿剥除术,比较两组手术时间、术中出血量、囊液外溢率、术后24 h视觉模拟评分法(VAS)评分。结果两组患者均顺利完成手术。两组手术时间比较差异未见统计学意义(P>0.05),观察组术中出血量明显少于对照组,囊液溢出率显著低于对照组,术后24 h切口疼痛VAS评分明显低于对照组,差异有统计学意义(P<0.05)。术后随访6~18个月,无囊肿复发。结论卵巢巨大囊肿及盆腔巨大囊性包块经术前严密评估后,行经脐单孔腹腔镜探查联合体外囊肿剥除术有显著优势,且安全可行,疗效可靠。

关键词：腹腔镜卵巢巨大囊肿体外剥除

High Energy Proton-Proton Elastic Scattering in Reggeon-Pomeron Exchange Model

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Communications in Theoretical Physics 2006年第6期45卷 1069-1072页

作者： ZHOU Li-Juan hu zhao-hui MA Wei-Xing Collaboration Group of Hadron Physics and Non-perturbative QCD Study Guangxi University of Technology Liuzhou 545006 China Institute of High Energy Physics the Chinese Academy of Sciences Beijing 100049 China Institute for Theoretical Physics the Chinese Academy of Sciences Beijing 100080 China

We initially propose a Reggeon-Pomeron exchange model to describe proton-proton elastic scattering at high energies in this short paper. A calculation for total cross section of proton-proton elastic scattering at high energies is performed without any free parameters. Our new finding from this work is that the Reggeon-Pomeron model gives a perfect fit to experimental data of the total cross section at the whole energy region where experimental data exist.

关键词： Reggeon-Pomeron model Reggeon Pomeron Regge theory high energy elastic scattering

The role of C-type natriuretic peptide in rat testes during spermatogenesis

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Asian Journal of Andrology 2011年第2期13卷 275-280页

作者： Dong-hui huang Shi-Wei Zhang hu zhao Ling Zhang Family Planning Research Institute Tongji Medical College Huazhong University of Science and Technology Wuhan 430030 China Centre Laboratory Zhongshan Hospital ofHubei Province Wuhan 430033 China Department of human Anatomy Tongji Medical College Huazhong University of Science and Technology Wuhan 430030 China

C-type natriuretic peptide （CNP） is a 22-amino acid peptide and act as a local paracrine or autocrine regulator. There is growing evidence that ChIP is involved in male reproductive processes. To investigate the role of CNPduring spermatogenesis, we measured the mRNA expression of CNPand its specific membrane-bound natriuretic peptide receptor-B （NPR-B） using real-time RT-PCR in the testes of normal rats on different postnatal days. After that spermatogenesis dysfunction model induced by ornidazole was established with the aim to study the correlation of CNPwith spermatogenic dysfunction. Then, Sertoli cells from 18- to 22-day-old healthy male rats were cultured in the presence of different CNPconcentrations （1 ×10-6, 1×10-7 and1×10-8 mol l-1）, and the mRNA expression levels of *** protein, inhibin B and transferrin were examined at 0 min, 30 min, 1 h, 2 h, 4 h, 8 h, 12 h, 24 h and 48 h. During the postnatal development of rat testes, the highest mRNA expression levels of CNPand NPR-B were found at postnatal Do, and the levels then declined gradually, with a second ChIPpeak at postnatal D35. In the ornidazole-induced infertile rat testes, CIVPgene expression was lower than in the uninduced rats （P〈0.05）, while IVPR-Bgene expression was greater （P〈0.05）. In cultured Sertoli cells, supplementation with CNP stimulated the gene expression of androgen-binding pmteirginhibin B/transferrin, particularly at 12 h, and 1× 10-7 mol l-1 CNP had the highest upregulation effect. The gene expression levels of CNPIIVPR-B in rat testes at different postnatal stages and in infertile rat testes indicated that CNP may participate in the physiology and/or pathology related to spermatogenesis. Moreover, ChIP regulated endocrine function in Sertoli cells. Taken together, these results showed that CNP is closely tied to spermatogenesis.

关键词： C-type natriuretic peptide natriuretic peptide receptor-B Sertoli cell culture spermatogenesis