检索结果-南通市图书馆

World Journal of Gastrointestinal Surgery 2024年第2期16卷 616-621页

作者： Sha-hong pu Wu-Yong-Ga Bao Zhen-Peng Jiang Rui Yang Qiang Lu Department of Medical Ultrasound West China Hospital of Sichuan UniversityChengdu 610041Sichuan ProvinceChina

BACKGROUND The overlap of imaging manifestations among distinct splenic lesions gives rise to a diagnostic ***,a definitive diagnosis primarily relies on his-tological *** ultrasound(US)-guided coaxial core needle biopsy(CNB)not only procures sufficient tissue to help clarify the diagnosis,but reduces the incidence of puncture-related *** SUMMARY A 41-year-old female,with a history of pulmonary tuberculosis,was admitted to our hospital with multiple indeterminate splenic ***-scale ultrasono-graphy demonstrated splenomegaly with numerous well-defined hypoechoic *** contrast-enhanced computed tomography(CT)showed an en-larged spleen with multiple irregular-shaped,peripherally enhancing,hypodense *** emission CT revealed numerous abnormal hyperglycemia *** imaging findings strongly indicated the possibility of infectious disease as the primary concern,with neoplastic lesions requiring *** obtain the precise pathological diagnosis,the US-guided coaxial CNB of the spleen was ca-rried *** patient did not express any discomfort during the *** Percutaneous US-guided coaxial CNB is an excellent and safe option for obtaining precise splenic tissue samples,as it significantly enhances sample yield for exact pathological analysis with minimum trauma to the spleen parenchyma and sur-rounding tissue.

关键词： Spleen Splenic disease Ultrasound Biopsy Ultrasound-guided coaxial core needle biopsy Case report

马克思主义视域下的“是”与“应当”——基于科玄论战的理论考察

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

前沿 2024年第2期 131-138页

作者：孙鸿溥韦洪发吉林大学马克思主义学院吉林长春130012

对“是”与“应当”关系的考量,学界往往局限于纯粹的知识论范式内,忽略其实质上是一个实践论问题;面对如今现实的实践需要,既有的答案业已力有不逮。因此,唯有跳出理论局限,以一种历史的视野为事实找寻价值属性、为价值觅得现实基础,... 详细信息

对“是”与“应当”关系的考量,学界往往局限于纯粹的知识论范式内,忽略其实质上是一个实践论问题;面对如今现实的实践需要,既有的答案业已力有不逮。因此,唯有跳出理论局限,以一种历史的视野为事实找寻价值属性、为价值觅得现实基础,才能为二者间的鸿沟架起稳固之桥。回看百年前的科玄论战,重新思考科学与玄学、因果律与自由意志、形而上与形而下的交锋,于细节处发微:一方面有助于看清科学派与玄学派论战的实质,即中国未来是全盘西化还是社会改良;另一方面证明事实与价值间的不可逾越,不会也不能满足中国的需要,只有历史唯物主义才是历史的选择,才是中国道路的理论依据。

关键词：科玄论战休谟问题唯物史观中国道路

基于加速度趋势调节的风电机组扇区工况控制研究

在线全文

学校读者我要写书评

暂无评论

水电站机电技术 2024年第6期47卷 1-3,12,144页

作者：蒲洪坚五凌电力有限公司湖南长沙410118

扇区管理技术可以确保风电机组安全稳定运行,但是传统风电扇区管理技术无法对风电机组进行精确控制,甚至会频繁导致机组停机,造成极大损失。为解决以上问题,本文提出了一种基于加速度趋势调节风电机组扇区工况的控制方法,该方法可以使... 详细信息

扇区管理技术可以确保风电机组安全稳定运行,但是传统风电扇区管理技术无法对风电机组进行精确控制,甚至会频繁导致机组停机,造成极大损失。为解决以上问题,本文提出了一种基于加速度趋势调节风电机组扇区工况的控制方法,该方法可以使风力发电机组进入扇区工况后在保障安全的情况下实现对机组的运行状态精确控制,能够有效提升风能利用效率,避免某些风况较差机位的发电机组频繁触发扇区管理停机造成的发电损失,可适用于各类风力发电机组处于扇区工况下的运行状态优化,并以五凌电力公司山西事业部风电运行数据为例分析了所提方法的有效性,为其他风力发电机组提供了参考应用。

关键词：风力发电加速度趋势扇区工况

基于高压密封的平衡单座调节阀设计与试验研究

在线全文

学校读者我要写书评

暂无评论

流体机械 2024年第1期52卷 14-22页

作者：余瑞明赵帅琦蒲洪陈东旭上海理工大学机械工程学院上海200093 浙江力诺流体控制科技股份有限公司浙江温州325200

针对目前高压密封工况,单一调节阀无法满足多种流量要求的现状,设计了一种高压工况用平衡单座调节阀。该阀阀芯设有平衡孔,设置密封圈与阀芯配合,密封圈嵌在平衡阀笼与降噪阀笼之间的安装槽内,阀芯的外锥面下方设有流量调节曲面,对其进... 详细信息

针对目前高压密封工况,单一调节阀无法满足多种流量要求的现状,设计了一种高压工况用平衡单座调节阀。该阀阀芯设有平衡孔,设置密封圈与阀芯配合,密封圈嵌在平衡阀笼与降噪阀笼之间的安装槽内,阀芯的外锥面下方设有流量调节曲面,对其进行高压密封试验和阀芯运动性能试验。结果表明,在高压工况下,可降低驱动执行器配置,密封圈与阀芯配合密封优良;流量调节曲面配合阀芯调节流量,满足不同工况要求。高压密封试验的试验压力实际值为0.35 MPa,泄漏量设定值为9.46 L/min,实测泄漏量为1.21 L/min;阀芯运动性能试验包括全行程及全开关时间试验、漂移与抖动试验、始动偏差值试验、基本误差与回差试验和死区试验,试验结果均满足要求;平衡单座调节阀密封优良,开闭时间远小于设定时间、实际偏差小于设定额定偏差(2.50%),已无漂移和抖动,实际信号值和行程值均小于设定值,正反向误差均小于设定基本误差,回差均小于设定回差,死区均小于设定死区值。研究结果对高压工况用调节阀的设计具有参考价值。

关键词：高压密封平衡单座调节阀设计试验

Fang-Howard wave function modelling of electron mobility in AlInGaN/AlN/InGaN/GaN double heterostructures

在线全文

学校读者我要写书评

暂无评论

Chinese Physics B 2021年第9期30卷 451-455页

作者： Yao Li hong-Bin pu Department of Electronic Engineering Xi'an University of TechnologyXi'an 710048China Key Laboratory of Wide Bandgap Semiconductor Materials Ministry of EducationXi'an 710071China Xi'an Key Laboratory of Power Electronic Devices and High Efficiency Power Conversion Xi'an 710048China

To study the electron transport properties in InGaN channel-based heterostructures,a revised Fang-Howard wave function is proposed by combining the effect of GaN back *** scattering mechanisms,such as dislocation impurity(DIS)scattering,polar optical phonon(POP)scattering,piezoelectric field(PE)scattering,interface roughness(IFR)scattering,deformation potential(DP)scattering,alloy disorder(ADO)scattering from InGaN channel layer,and temperature-dependent energy bandgaps are considered in the calculation model.A contrast of AlInGaN/AlN/InGaN/GaN double heterostructure(DH)to the theoretical AlInGaN/AlN/InGaN single heterostructure(SH)is made and analyzed with a full range of barrier alloy *** effect of channel alloy composition on InGaN channel-based DH with technologically important Al(In,Ga)N barrier is estimated and optimal indium mole fraction is 0.04 for higher mobility in DH with Al_(0.4)In_(0.07)Ga_(0.53)N ***,the temperature-dependent two-dimensional electron gas(2DEG)density and mobility in InGaN channel-based DH with Al_(0.83)In_(0.13)Ga_(0.04)N and Al_(0.4)In_(0.07)Ga_(0.53)N barrier are *** results are expected to conduce to the practical application of InGaN channel-based heterostructures.

关键词： scattering mechanism double heterostructures electron mobility InGaN channel

Platinum Atoms Dispersed in Single-chain Polymer Nanoparticles

在线全文

学校读者我要写书评

暂无评论

Chinese Journal of Polymer Science 2021年第4期39卷 441-446,I0005页

作者： Zhi-Yu Hu hong-Ting pu Jian-Guo Wu Department of Polymeric Materials School of Materials Science&EngineeringTongji UniversityShanghai 201804China Key Laboratory of Advanced Civil Engineering Materials School of Materials Science&EngineeringTongji UniversityShanghai 201804China

The intramolecular cross-linking of single polymer chains can form single-chain nanoparticles(SCNPs),which have many *** this study,styrenic copolymers with pendent triphenylphosphine as the coordination site for platinum ions(Pt(Ⅱ))and benzocyclobutene as the latent reactive groups are *** groups in the chains can coordinate Pt(Ⅱ)and aid slight single-chain folding in dilute *** intramolecular cross-linking caused by the ring-open reaction of benzocyclobutene completes the single-chain collapse and forms stable SCNPs in dilute ***(Ⅱ)embedded in SCNPs can be further reduced to platinum atoms(Pt(0)).Pt(0)steadily and atomically dispersed in SCNPs exhibits better catalytic properties than normal polymer carried platinum particles do for the reduction of p-nitrophenol to p-aminophenol.

关键词： Single-chain Polymer nanoparticles Intramolecular cross-linking Platinum Coordination

在线全文

学校读者我要写书评

暂无评论

磷石膏动模量及阻尼比试验研究

中国测试 2024年第5期50卷 11-18页

作者：蔡国军卫俊仁杨森林蒲洪李林地质灾害防治与地质环境保护国家重点实验室(成都理工大学) 四川成都610059 成都理工大学地质工程国家级实验教学示范中心四川成都610059

近年来,磷石膏废渣的生产和堆积迅速增长,给库区安全以及环境带来不小的隐患。该文利用英国GDS公司的GDS-DYNTTS型微机控制振动三轴试验系统,对杨家箐磷石膏堆场库区不同取土深度下的磷石膏废渣进行动力特性试验,主要针对其在围压较大... 详细信息

近年来,磷石膏废渣的生产和堆积迅速增长,给库区安全以及环境带来不小的隐患。该文利用英国GDS公司的GDS-DYNTTS型微机控制振动三轴试验系统,对杨家箐磷石膏堆场库区不同取土深度下的磷石膏废渣进行动力特性试验,主要针对其在围压较大、偏压固结条件下的动弹性模量E_(d)、阻尼比λ进行较详细的研究。试验结果表明:密度相同条件下,动弹性模量随着固结比和围压的增加而变大,且在动应变ε_(d)增长初期曲线变化率不大,ε_(d)超过0.01%后动弹性模量会迅速减小,再逐渐趋于平缓;利用Kondner模型发现最大动弹性模量倒数和动应变的曲线呈较好的线性关系;对动模量比(E_(d)/E_(d0))曲线进行归一化分析,可以得出动模量与动应变的变化趋势,并且根据Darendeli模型对磷石膏动模量比的衰变阶段进行划分;利用最小二乘法对阻尼比与动弹性模量比λ-Ed/Ed0分布进行拟合,得到归一性较好的经验模型曲线。

关键词：动三轴试验磷石膏偏压固结动模量阻尼比

同方期刊数据库博看期刊评论

在线全文

学校读者我要写书评

暂无评论

核电站特殊区域核级波纹管截止阀的设计研究

阀门 2024年第6期 673-678页

作者：王浩刘涵何展鸿戴彬魏宏璞中广核工程有限公司广东深圳518124 苏州纽威阀门股份有限公司江苏苏州215129

本文提供了一种核级无阀盖波纹管截止阀的详细结构方案,开展了该阀门流量特性、阀门刚度及抗震性能等方面的设计验证,确保阀门满足华龙一号最新核电技术的要求;并通过对该型号阀门制造过程的规划,提供了一套完整的核电站日常维修不可达... 详细信息

本文提供了一种核级无阀盖波纹管截止阀的详细结构方案,开展了该阀门流量特性、阀门刚度及抗震性能等方面的设计验证,确保阀门满足华龙一号最新核电技术的要求;并通过对该型号阀门制造过程的规划,提供了一套完整的核电站日常维修不可达区域波纹管截止阀的解决方案。

关键词：波纹管截止阀维修不可达无阀盖模块化设计

Effect of pre-tensioned rock bolts on stress redistribution around a roadway—insight from numerical modeling

在线全文

学校读者我要写书评

暂无评论

Journal of China University of Mining and Technology 2008年第4期18卷 509-515页

作者： GAO Fu-qiang KANG hong-pu Mining and Designing Branch Central Coal Research Institute Beijing 100013 China

The importance of the pre-tensioned force of rock bolts has been recognized by more and more researchers. To investi- gate the effect of pre-tensioned rock bolts on stress redistribution around roadways, a numerical analysis was carried out using FLAC3D and a special post-process methodology, using surfer, is proposed to process the numerical simulation results. The results indicate that pre-tensioned rock bolts have a significant effect on stress redistribution around a roadway. In the roof, pre-tensioned rock bolts greatly increase vertical stress; as a result, the strength of the rock mass increased significantly which results in a greater capacity of bearing a large horizontal stress. The horizontal stress decreases in the upper section of the roof, indicating that pre-tensioned rock bolts significantly reduce the coefficient and the size of the region concentration of horizontal stress. At the lat- eral side, pre-tensioned rock bolts greatly increase the horizontal stress; therefore, the rock mass strength significantly increases which results also in a greater capacity of bearing a large vertical stress. The greater the size of pre-tensioned force, the larger the region of stress redistribution around a roadway is affected and the higher the size of the stress on the roadway surface the more the rock mass strength increases.

关键词： pre-tensioned rock bolts stress redistribution numerical simulation

Ultra-high voltage 4H-SiC gate turn-off thyristor for low switching time

在线全文

学校读者我要写书评

暂无评论

Chinese Physics B 2019年第12期28卷 303-310页

作者： Qing Liu hong-Bin pu Xi Wang Xi'an University of Technology Xi'an 710048 China

An ultra-high voltage 4H-silicon carbide(Si C) gate turn-off(GTO) thyristor for low switching time is proposed and analyzed by numerical simulation. It features a double epitaxial p-base in which an extra electrical field is induced to enhance the transportation of the electrons in the thin p-base and reduce recombination. As a result, the turn-on characteristics are improved. What is more, to obtain a low turn-off loss, an alternating p^+/n^+region formed in the backside acts as the anode in the GTO thyristor. Consequently, another path formed by the reverse-biased n^+–p junction accelerates the fast removal of excess electrons during turn-off. This work demonstrates that the turn-on time and turn-off time of the new structure are reduced to 37 ns and 783.1 ns, respectively, under a bus voltage of 8000 V and load current of 100 A/cm^2.

关键词： 4H-SiC gate turn-off(GTO) thyristor turn-on turn-off