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气管插管后早期胃肠减压对机械通气患者呼吸力学的影响

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中国急救医学 2024年第1期44卷 88-92页

作者：任佳乐王志伟张伟杨建中新疆医科大学护理学院新疆乌鲁木齐830000 新疆医科大学第一附属医院急救中心新疆乌鲁木齐830054

目的探讨气管插管后早期进行胃肠减压对机械通气患者呼吸力学的影响及其临床应用价值。方法本研究为前瞻性观察性研究,将新疆医科大学第一附属医院急诊抢救室2023年3月至2023年6月接受气管插管后机械通气的132例患者分为观察组(n=66)和... 详细信息

目的探讨气管插管后早期进行胃肠减压对机械通气患者呼吸力学的影响及其临床应用价值。方法本研究为前瞻性观察性研究,将新疆医科大学第一附属医院急诊抢救室2023年3月至2023年6月接受气管插管后机械通气的132例患者分为观察组(n=66)和对照组(n=66)。观察组在气管插管后的1 h内进行胃肠减压,对照组在气管插管后的6 h内未进行胃肠减压治疗。收集两组患者的一般资料,并在气管插管即刻(T0)、机械通气1 h(T1)、机械通气2 h(T2)、机械通气4 h(T3)、机械通气6 h(T4)时分别测量两组患者的呼吸力学参数、氧合及腹内压变化情况进行并分析。结果在T0时,两组的呼吸力学指标差异均无统计学意义(P>0.05),两组的气道峰压(Ppeak)均下降差异无统计学意义(P>0.05);在T3和T4时,观察组的平台压(Pplat)和平均气道压(Pmean)显著低于对照组,静态顺应性(Cstat)显著高于对照组,差异均有统计学意义(P<0.05);在T1后,观察组的PaO 2/FiO 2显著高于对照组(P<0.05);在T4时,观察组的腹内压显著低于对照组(P<0.05)。结论在气管插管后1 h内进行胃肠减压能够有效改善机械通气患者的呼吸力学指标,降低腹内压,提高肺部顺应性和氧合情况。

关键词：气管插管早期胃肠减压平台压平均气道压气道峰压静态顺应性腹内压氧合

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双层合采油井盲管控水机理数值模拟

断块油气田 2024年第2期31卷 351-356页

作者：施明华陈德春王志伟王鹏华王亮亮陈毅王杰祥中国石油大学(华东)石油工程学院山东青岛266580 中国石化胜利油田分公司海洋采油厂山东东营257237

依托胜利油田盲管控水先导开发试验项目,根据双层合采油井油水流入动态特征,建立了双层合采油井盲管控水模型,并利用Fluent软件开展不同长度与不同位置盲管作用下的双层合采油井地层产液特征数值模拟研究。结果表明:盲管可以增加高含水... 详细信息

依托胜利油田盲管控水先导开发试验项目,根据双层合采油井油水流入动态特征,建立了双层合采油井盲管控水模型,并利用Fluent软件开展不同长度与不同位置盲管作用下的双层合采油井地层产液特征数值模拟研究。结果表明:盲管可以增加高含水层的井底流压,降低地层产液流量。对于综合含水率达到80%的双层合采油井,盲管长度是影响其控水效果的主要因素,盲管越长,控水效果越明显。与无盲管相比,在2 m的高含水层全段放置盲管,产液含水率可降低30百分点。盲管位置是影响其控水效果的次要因素,在2 m的高含水层不同位置放置0.5 m盲管,产液含水率下降约3百分点。为保障控水效果,应针对高含水层所在位置,放置适应地层厚度的盲管,调控双层合采油井产液流量,达到控水的目的。在优化双层合采油井盲管长度和盲管位置的基础上,利用流体数值模拟对盲管的控水机理进行了深入研究,研究结果能为高含水油藏双层或多层合采油井实施盲管控水开采提供技术指导。

关键词：多层合采盲管调流控水数值模拟

Effect of surfactant addition on leaching process of weathered crust elution-deposited rare earth ores with magnesium sulfate

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矿业科学技术学报:英文版 2023年第8期33卷 1045-1053页

作者： Fang Zhou Lisen Zhang zhiwei wang Yixin Zhang Ruan Chi Key Laboratory for Green Chemical Process of Ministry of Education Wuhan Institute of TechnologyWuhan 430073China

Surfactants were proposed to be added into magnesium sulfate solution to improve the leaching process of weathered crust elution-deposited rare earth ores(WREOs).Effects of surfactants and their concentration on the seepage of leaching solutions and the leaching efficiency of rare earth(RE)and aluminum(Al)were investigated,and the leaching kinetics,the mass transfer process,the adhesion work and the adhesion work reduction factor were analyzed to reveal its strengthening leaching *** results show that cetyltrimethylammonium bromide(CTAB)has a better strengthening effect on the leaching process than dodecyl trimethyl ammonium bromide(DTAB),sodium dodecyl sulfate(SDS),sodium oleate and oleic *** the presence of 0.04%CTAB in 0.2 mol/L solution,the permeability coefficient of WREOs increases from 0.945×10^(-5)to 1.640×10^(-5)cm·s^(-1),and the leaching efficiency of RE increases from 80%to 90%,confirming the promotion of surfactants on the leaching process of *** analysis shows that the leaching process conforms to the inner diffusion control model,and the leaching kinetics equations of RE and Al related to CTAB content are *** transfer discussion shows a smaller height equivalent to theoretical plate(HETP)of RE and Al at CTAB content of 0.04%,suggesting the higher mass transfer efficiency *** to the interfacial properties of leaching solutions,the calculated adhesion work and the adhesion work reduction factor further demonstrate the strengthening leaching effect of CTAB on the leaching process of WREOs.

关键词： Weathered crust elution-deposited rare earth ores Surfactant Kinetics Mass transfer

六自由度搬运机械手轨迹规划及刚柔耦合运动分析

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河南工程学院学报（自然科学版） 2024年第2期36卷 37-41页

作者：李晓光王志伟安徽粮食工程职业学院机电工程系安徽合肥230011 宝时得科技(中国)有限公司江苏苏州215000

针对零部件加工生产时多工序流水作业带来的高强度劳动问题,提出了一种基于自动搬运机械手的解决方案,以完成特定的工作要求。结合实际工况对机械手进行Creo三维模型建立,同时利用萨哈D-H坐标法建立运动学方程,求解出机械手末端轨迹的位... 详细信息

针对零部件加工生产时多工序流水作业带来的高强度劳动问题,提出了一种基于自动搬运机械手的解决方案,以完成特定的工作要求。结合实际工况对机械手进行Creo三维模型建立,同时利用萨哈D-H坐标法建立运动学方程,求解出机械手末端轨迹的位姿,再借助ADAMS和HyperMesh完成对机械手的轨迹规划及刚柔耦合运动分析,完成机械手的运动参数设置及关键部件强度分析,验证了设计的合理性,为机械手的轨迹规划及设计提供了重要参考。

关键词：机械手萨哈D-H坐标 ADAMS HyperMesh 刚柔耦合

Sharing of Encrypted Lock Keys in the Blockchain-Based Renting House System from Time- and Identity-Based Proxy Reencryption

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China Communications 2022年第5期19卷 164-177页

作者： zhiwei wang Liping Qian Danwei Chen Guozi sun School of Computer Nanjing University of Posts and TelecommunicationsNanjing 210023China Jiangsu Key Laboratory of Big Data Security and Intelligent Processing Nanjing 210023China Guangxi Key Laboratory of Cryptography and Information Security Department of Computer SciencesGuilin University of Electronic TechnologyGuilin 541004China

To design an efficient protocol for sharing the encrypted lock keys in the renting house system,we introduce a new notion called time-and identitybased proxy reencryption(TIPRE)and the blockchain *** CPA secure TIPRE scheme is constructed from Green et al.’s identity-based proxy reencryption scheme by adding the time *** every time period,a time stamp authority generates a public key embedded with the current time stamp for each *** our protocol for the renting house system,the TIPRE scheme is the primary building block,and the blockchain platform serves instead of a trusted third party,such as a real estate agency between landlords and *** TIPRE scheme allows the landlord to change the lock key at each time period for *** blockchain platform allows the landlords and tenants to directly interact,and all of the interactions are recorded in the blockchain database to provide the desired security requirements,such as nonrepudiation and ***,we provide the secure analysis of our protocol and test its performance by implementing it in the MacBook Pro and the Intel Edison development platforms.

关键词： identity-based proxy reencryption time stamp renting houses system blockchain

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工控协议安全研究综述

通信学报 2024年第6期45卷 60-74页

作者：黄涛王郅伟刘家池龙千禧况博裕付安民张玉清南京理工大学计算机科学与工程学院江苏南京210094 中国科学院大学国家计算机网络入侵防范中心北京101408 中关村实验室北京100194 海南大学网络空间安全学院(密码学院) 海南海口571835

工控协议安全是保障ICS稳定运行的关键,大量工控协议在设计阶段忽视了对安全性的考量,导致目前大部分主流工控协议普遍存在脆弱性问题。结合ICS架构和工控协议的发展特征,深入解析目前工控协议普遍面临的脆弱性问题和攻击威胁。同时,针... 详细信息

工控协议安全是保障ICS稳定运行的关键,大量工控协议在设计阶段忽视了对安全性的考量,导致目前大部分主流工控协议普遍存在脆弱性问题。结合ICS架构和工控协议的发展特征,深入解析目前工控协议普遍面临的脆弱性问题和攻击威胁。同时,针对工控协议的潜在漏洞,深入分析基于静态符号执行、代码审计和模糊测试等工控协议漏洞挖掘技术,并从工控协议的规范设计、通信机制以及第三方中间件3个方面全面剖析协议设计的安全防护技术。另外,从沙箱研制、安全防护及漏洞挖掘等方面,对工控协议安全的未来发展趋势进行展望。

关键词： ICS 工控协议协议脆弱性安全防护漏洞挖掘

Revocable Broadcast Encryption with Constant Ciphertext and Private Key Size

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Chinese Journal of Electronics 2019年第4期28卷 690-697页

作者： JIA Hongyong CHEN Yue YANG Kuiwu GUO Yuanbo wang zhiwei Zhengzhou University State Key Laboratory of Mathematical Engineering and Advanced Computing Nanjing University of Post and Communications

In a revocable broadcast encryption scheme, the group manager can flexibly set revoked users who cannot decrypt the ciphertext. Many applications of the revocable broadcast encryption have been found in the secure cloud data sharing. An adaptively secure revocable broadcast encryption system with constant ciphertext and private key size under standard assumptions is more suitable for use in the cloud environment. Few existing revocable broadcast encryption schemes meet such a requirement. We propose a revocable broadcast encryption scheme with constant size ciphertext and private key by combining the RSA cryptographic accumulator with an efficient identity based encryption system. We prove it to be adaptively secure under standard assumptions using dual system encryption techniques.

关键词： Cryptographic accumulator Broadcast encryption Revocable Dual system encryption Cloud data sharing

Supported catalytic packing prepared from ceramic packing for reactive distillation of ethyl acetate

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Chinese Journal of Chemical Engineering 2022年第10期50卷 205-214页

作者： zhiwei wang Jiannan Shi Xiaonan Liu Zhikai Cao Yong Sha Department of Chemical and Biochemical Engineering College of Chemistry and Chemical EngineeringXiamen UniversityXiamen 361005China

In this work,a strategy of"etching-modification filling-graft copolymerization"was proposed to load the acidic ionic polyionic liquid on the smooth ceramic *** this way,commercial ceramic Raschig rings were successfully transformed into the supported catalytic packing for the reactive distillation,and were further evaluated with esterification reaction of ethyl acetate by means of the fully mixed reactor,the ultrasonic destruction,the cyclic catalysis reaction and the lab-scale distillation column *** catalyst coating has good adhesion with the *** can withstand 24 h of ultrasound damage and shows good stability in three cycle catalytic *** kind of coated catalyst has better catalytic activity than the commercial Amberlyst 15 *** the lab-scale reaction distillation,the supported catalyst Raschig ring can achieve a higher conversion in comparison with the tea bag catalytic packing of Amberlyst 15 dry under some conditions.

关键词： Supported catalyticpacking Ethyl acetate Reactive distillation Bonding strength

Simulation and assessment of sludge concentration and rheology in the process of waste activated sludge treatment

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Journal of Environmental Sciences 2009年第12期21卷 1639-1645页

作者： XIA Mingfang wang zhiwei WU Zhichao wang Xinhua ZHOU Zhen LU Jilai State Key Laboratory of Pollution Control and Resource Reuse Nanjing University Nanjing 210093 China State Key Laboratory of Pollution Control and Resource Reuse School of Environmental Science and Engineering Tongji University Shanghai 200092 China

The process of using flat-sheet membrane for simultaneous sludge thickening and digestion （MSTD） was employed. The variations of sludge concentration and rheology were characterized and simulated. Based on mass balance analysis, mathematical models were developed and successfully used to predict and evaluate the variations of sludge concentration and the digestion efficiency in the MSTD process. The apparent viscosity of sludge could be modeled as functions of mixed liquor suspended solids and shear rates. The sludge in the MSTD process showed both shear-thinning and viscoplastic behaviour, and under various shear rates different rheological models could be chosen to predict their flow behaviour. It was also found that sludge concentration and viscosity had significant correlations with membrane fouling in the MSTD process.

关键词： membrane filtration membrane fouling sludge thickening sludge digestion waste activated sludge