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逆向建轨单内嵌分支覆膜支架技术修复复杂B型主动脉夹层1例

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局解手术学杂志 2024年第3期33卷 276-278页

作者：肖寒潘文旭钱德慧陆军军医大学第二附属医院心血管内科重庆400037

B型主动脉夹层是心血管危急重症之一,具有发病急骤、进展快、病死率极高的特点。目前临床上可采用外科手术或腔内修复术治疗,其中腔内修复术相较于外科手术具有创伤小、恢复快、预后好等优势[1],已逐渐成为B型主动脉夹层治疗的首选方式... 详细信息

B型主动脉夹层是心血管危急重症之一,具有发病急骤、进展快、病死率极高的特点。目前临床上可采用外科手术或腔内修复术治疗,其中腔内修复术相较于外科手术具有创伤小、恢复快、预后好等优势[1],已逐渐成为B型主动脉夹层治疗的首选方式。但对于破口累及左锁骨下动脉的B型主动脉夹层,过去常因锚定区不足等原因,一度成为腔内修复术治疗的相对禁忌证。

关键词：逆向建轨单内嵌分支支架主动脉夹层

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切顶成巷技术在煤矿开采中的价值分析

价值工程 2024年第13期43卷 13-16页

作者：车德高朱长海姜晨黑龙江省应急管理厅哈尔滨150000 七台河岚峰矿业有限公司七台河154500 黑龙江科技大学哈尔滨150022

本研究针对黑龙江鸡西矿业集团有限责任公司下属煤矿面临的采掘接替紧张与回采率低下两大难题,运用价值工程的七个逻辑程序,进行了深入分析与解决方案设计。通过现场勘探与数据整理,本研究确认切顶自成巷技术为有效解决方案,该技术旨在... 详细信息

本研究针对黑龙江鸡西矿业集团有限责任公司下属煤矿面临的采掘接替紧张与回采率低下两大难题,运用价值工程的七个逻辑程序,进行了深入分析与解决方案设计。通过现场勘探与数据整理,本研究确认切顶自成巷技术为有效解决方案,该技术旨在优化采掘布局,提升安全性和经济效益。在严格遵循价值工程逻辑程序的基础上,提出了包含“切、补、护、支”四个环节的改进方案,并通过矿压监测确保技术功能满足实际需求。经过成本与价值分析,确定该方案具有显著的经济效益和安全效益。据预测,实施切顶自成巷技术后,矿井将实现采掘接替的有效缓解,回采率显著提升,并有望为矿井带来约6761万元的额外收益。研究不仅为鸡西矿业集团解决了实际问题,也为类似条件的煤矿提供了可行的技术路径与参考。未来,将继续关注技术应用效果,不断优化完善,推动矿业安全与效益的双提升。

关键词：价值工程切顶成巷中厚煤层顶板支护

维普期刊数据库博看期刊

Comparison of Pb,Cd Adsorption to Surface Coatings developed in Natural Waters with that in Plant Effluents

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Chemical Research in Chinese Universities 2003年第4期19卷 417-421页

作者： DoNG de-ming LI Yu HUA Xiu-yi ZHANG Jing-jing College of Environment and Resources Jilin UniversityChangchun 130023P.R.China

The comparative studies of Pb and Cd adsorption to the surface coatings(Fe, Mn, Al oxides, organic materials, and associated minerals), which were developed on glass slides in five natural and two technical waters(plant effluents), were carried out under controlled laboratory conditions(mineral salts solution with defined speciation, ionic strength 0 05 mol/L, 25 ℃ and pH 6 0). The classical Langmuir adsorption isotherm was applied to estimating the equilibrium coefficients of Pb and Cd adsorption to the surface coatings. The results show that the maximum adsorption of Pb and Cd to the surface coatings mentioned above varied widely. There was a systemic increase in the maximum adsorption of Pb and Cd to the surface coatings with increasing the contents of Mn and Fe oxides in the surface coatings in significant correlation, respectively, not only highlighting the relative importance of the metal oxide fraction for Pb and Cd adsorption to the surface coatings developed in natural and technical water samples, but also implying the same adsorption mechanisms of Pb and Cd to the surface coatings developed both in natural and technical water samples.

关键词： Natural waters Plant effluents Surface coatings Pb Cd

Humidity Effects on Conductivity of DNA Molecules

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Communications in Theoretical Physics 2006年第2X期46卷 381-384页

作者： YAN Xun-Ling DoNG Rui-Xin LIN Qing-de School of Physical Science and Information Engineering Liaocheng University Liaocheng 252059 China College of Radiology Taishan Medical University Taian 271000 China

We present a model related to the humidity to describe the conductivity of homogeneous DNA molecule, where the hydration of phosphate group and bases are taken into account. The calculated results show the oscillation feature of dI/dV-V curves and the semiconductor behavior of DNA. With the relative humidity increasing, the voltage gap becomes narrow and the maximum of conductance increases nonlinearly. The conductivity of DNA approaches to stabilization when the relative humidity reaches a certain value. These results are in agreement with experimental measurements.

关键词： DNA conductivity humidity

Single gate optimization for plastic injection mold

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2007年第7期8卷 1077-1083页

作者： LI Ji-quan LI de-qun GUo Zhi-ying LV Hai-yuan department of Plasticity Technology Shanghai Jiao Tong University Shanghai 200030 China

This paper deals with a methodology for single gate location optimization for plastic injection mold. The objective of the gate optimization is to minimize the warpage of injection molded parts, because warpage is a crucial quality issue for most injection molded parts while it is influenced greatly by the gate location. Feature warpage is defined as the ratio of maximum displacement on the feature surface to the projected length of the feature surface to describe part warpage. The optimization is combined with the numerical simulation technology to find the optimal gate location, in which the simulated annealing algorithm is used to search for the optimum. Finally, an example is discussed in the paper and it can be concluded that the proposed method is effective.

关键词： Injection mold Gate location optimization Feature warpage

one-step synthesis of hollow Uo2 nanospheres via radiolytic reduction of ammonium uranyl tricarbonate

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Chinese Chemical Letters 2017年第2期28卷 197-200页

作者： Yong-Ming Wang Qing-de Chen Xing-Hai Shen Beijing National Laboratory for Molecular Sciences Fundamental Science on Radiochemistry and Radiation Chemistry Laboratory Department of Applied Chemistry College of Chemistry and Molecular Engineering Peking University Beijing 100871 China

Black precipitates were successfully obtained by radiolytic reduction of ammonium uranyl tricarbonate in the aqueous solution of HCooNH_4 by one ***,SAED,EDS,and XRD analysis indicated that the precipitates consist of hollow Uo2 nanospheres（φ：30-50 nm,wall thickness：8-15 nm,and cavity diameter：10-20 nm）.The effect of HCooNH4 concentration,irradiation time and dose rate on the morphology,and size of nanospheres was ***,a gas-bubble template mechanism was proposed.

关键词： Uranium dioxide Hollow nanospheres Ammonium uranyl tricarbonate(AUC) Hydrated electron(eaq^-) γ-Irradiation

Rearrangements in Carnot Groups

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Acta Mathematica Sinica,English Series 2019年第7期35卷 1115-1127页

作者： Juan J. MANFREDI Virginia N. VERA de SERIo department of Mathematics University of Pittsburgh Pittsburgh PA 15260 USA Facultad de Ciencias Econdmicas Universidad Nacional de Cuyo 5500 Mendoza Argentina

In this paper we extend the notion of rearrangement of nonnegative functions to the setting of Carnot groups. We define rearrangement with respect to a given family of anisotropic balls Br , or equivalently with respect to a gauge‖x‖, and prove basic regularity properties of this construction. If u is a bounded nonnegative real function with compact support, we denote by u*its rearrangement. Then, the radial function u* is of bounded variation. In addition, if u is continuous then u* is continuous, and if u belongs to the horizontal Sobolev space W 1,ph , then Dhu*(x)/Dh( ‖x‖ )| is in Lp. Moreover, we found a generalization of the inequality of P(o)lya and Szeg(o) ∫|Dhu*|p/Dh(‖x‖)|pdx≤C ∫|Dhu|pdx,where p ≥ 1.

关键词： Symmetrization rearrangements Carnot groups

Position/Force Hybrid Control System for High Precision Aligning of Small Gripper to Ring object

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International Journal of Automation and computing 2013年第4期10卷 360-367页

作者： Juan Zhang de Xu Zheng-Tao Zhang Wen-Sheng Zhang Research Center of Precision Sensing and Control Institute of Automation Chinese Academy of Sciences

A position/force hybrid control system based on impedance control scheme is designed to align a small gripper to a special ring object. The vision information provided by microscope vision system is used as the feedback to indicate the position relationship between the gripper and the ring object. Multiple image features of the gripper and the ring object are extracted to estimate the relative positions between them. The end-effector of the gripper is tracked using the extracted features to keep the gripper moving in the field of view. The force information from the force sensor serves as the feedback to ensure that the contact force between the gripper and the ring object is limited in a small safe range. Experimental results verify the effectiveness of the proposed control strategy.

关键词： Feature extraction position/force hybrid control movement control microscope vision micro-assembly.

Theoretical Study on Efficiency of Anti-explosion and Fireproof Agents

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Chinese Journal of Chemistry 2005年第11期23卷 1503-1509页

作者： HUANG, Chao YANG, Xu-Jie LU, Lu-de WANG, Xin Materials Chemistry Laboratory Nanjing University of Science and Technology Nanjing Jiangsu 210094 China Jiangsu Police Institute Nanjing Jiangsu 210012 China

Multi-protection is a principle in security management, and the use of anti-explosion and fireproof agents is a crucial part of it. In this paper, the properties of nano-oxide particles in the field of anti-explosion and fireproof were analyzed. The sedimentation velocity of nanometer particles was calculated. CH4 was taken as an example, and its combustion mechanism of the initial stages was concluded. The effects of 15 oxides on molecular energies of the reaction system were calculated with program Hyperchem 6, and the possible contact manner between radi- cals and oxides was got. It was concluded that oxides, such as Zro2, could combine with radicals, and thus prevent the combustion reaction. It was found that the nano-Zro2 eruptively generated aerosol is superior to other counterparts in serving as the anti-explosion and fireproof agent, and therefore, will play an increasingly important role in the security management.

关键词： nanometer aerosol eruptively generated aerosol anti-explosion and fireproof agent