检索结果-南通市图书馆

Effects of electric-acoustic and acoustic-electric conversions of transducers on acoustic logging signal

在线全文

学校读者我要写书评

暂无评论

Chinese Science Bulletin 2012年第11期57卷 1246-1260页

作者： fa Lin XIE WenYan TIAN Yong ZHAO MeiShan ma Li DONG DaQun School of Electronics Engineering Xi'an University of Post and TelecommunicationsXi'an 710121China PetroChina Liaohe Oilfield Company Panjin 124013China The James Franck Institute and Department of Chemistry The University of ChicagoChicagoIL 60637USA Department of Digital Media andArt Xi'an University of Post and TelecommunicationsXi'an 710121China School of marine Engineering Northwest Polytechnical UniversityXi'an 710071China

Based on an acoustic logging transmission network and the engineering pattern of a sliding wave in acoustic logging, analysis and calculations have been performed in a study of the effects of the electric-acoustic and acoustic-electric conversions of the transducers on the acoustic logging signal. The results show that acoustic-electric conversion through the transducer can cause not only a serious disturbance in the signal amplitude, but also an apparent transmission delay. For engineering applications, the amplitude variation and transmission delay must be accounted for in a practical analysis of the acoustic logging signal in rocks. The results also show that with enhanced understanding and proper justification, the error caused by the acoustic-electric conversion can be significantly reduced in evaluation of the cement bond quality of a cased well, and the accuracy of rock porosity calculated using the measured acoustic velocity can be increased.

关键词：声波测井测井信号换能器电声声电转换传输网络信号幅度传输延迟

Knots and Polynomials

在线全文

学校读者我要写书评

暂无评论

Journal of mathematical Research and Exposition 2010年第2期30卷 257-264页

作者： You fa HAN Xiao Sha ma School of mathematics Liaoning Normal University Liaoning 116029 P. R. China

In this paper, we deal with some corresponding relations between knots and polynomials by using the basic properties of knot polynomials （such as, some special values of knot polynomials, the Arf invariant and derivative of knot polynomials）. We give necessary and sufficient conditions that a Laurent polynomial with integer coefficients, whose breadth is less than five, is the Jones polynomial of a certain knot.

关键词： knot Jones polynomial Laurent polynomial.

噻托溴铵联合布地奈德吸入治疗对哮喘-慢阻肺重叠综合征患者肺功能和睡眠质量的影响

在线全文

学校读者我要写书评

暂无评论

河北医学 2024年第8期30卷 1309-1315页

作者：王保兰王亮马婷南京医科大学附属淮安第一医院呼吸与危重症医学科江苏淮安223000

目的:评估噻托溴铵联合布地奈德吸入治疗对哮喘-慢阻肺重叠综合征(ACOS)患者肺功能和睡眠质量的影响。方法:以2019年1月至2024年1月在本院接受治疗的98例ACOS患者为样本。采用随机数字表法简单随机等分分为两组,每组49例。对照组采用布... 详细信息

目的:评估噻托溴铵联合布地奈德吸入治疗对哮喘-慢阻肺重叠综合征(ACOS)患者肺功能和睡眠质量的影响。方法:以2019年1月至2024年1月在本院接受治疗的98例ACOS患者为样本。采用随机数字表法简单随机等分分为两组,每组49例。对照组采用布地奈德吸入治疗,观察组在对照组的基础上联合应用噻托溴铵,两组均连续治疗3个月。比较两组患者治疗前后的炎症水平[白介素6(IL-6)、肿瘤坏死因子α(TNF-α)、超敏C反应蛋白(hs-CRP)]、免疫功能[辅助性T细胞17(Th17)、调节性T细胞(Treg)、Th17/Treg]、气道重塑因子[转化生长因子-β1(TGF-β1)、骨桥蛋白(OPN)、基质金属蛋白酶-9(MMP-9)]、肺功能[第1秒用力呼气容积(FEV1)、用力肺活量(FVC)、每分钟最大自主通气量(MVV)]。并通过慢性阻塞性肺疾病评分(CAT)、哮喘患者症状评分(ACT)评估患者治疗前后的疾病症状,并在治疗3个月后通过匹兹堡睡眠质量指数(PSQI)量表比较两组睡眠质量。结果:治疗前,两组患者血清炎性因子、Th17、Th17/Treg、气道重塑因子水平、肺功能、CAT和PSQI评分差异无统计学意义(P>0.05);较治疗前,两组治疗后血清IL-6、TNF-α、hs-CRP、Th17、Th17/Treg、TGF-β1、OPN、MMP-9水平、ACT、CAT评分均下降,Treg水平、肺功能FEV1、FVC、MVV水平均升高,差异有统计学意义(P<0.05);两组血清炎性因子、Th17、Th17/Treg、气道重塑因子水平、肺功能、CAT和PSQI评分治疗前后差值比较,差异有统计学意义(P<0.05);观察组治疗后的睡眠状况优于对照组,差异有统计学意义(P<0.05)。结论:在ACOS的治疗中联合应用噻托溴铵和布地奈德有助于改善的肺功能和睡眠质量。

关键词：噻托溴铵布地奈德哮喘-慢阻肺重叠综合征肺功能睡眠质量

Synthesis,formation mechanism,and intrinsic physical properties of several As/P-containing maX phases

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

Journal of materials Science & Technology 2023年第2期133卷 23-31页

作者： Hongxiang Chen Sheng Li Jun Deng Zhilong Zhang Jianeng Huang fa Chang Li Huang Shixuan Du Pinqiang Dai School of materials Science and Engineering Fujian University of TechnologyFuzhou 350118China Institute of Physics&University of Chinese Academy of Sciences Chinese Academy of SciencesBeijing 100190China Fujian Provincial Key Laboratory of Advanced materials Processing and Application Fuzhou 350118China Center for Advanced Energy and Functional materials Fujian University of TechnologyFuzhou 350118China Songshan Lake materials Laboratory Dongguan 523808China CAS Key Laboratory of Vacuum Physics Beijing 100049China

321 phases are an atypical series of maX phases,in which A=As/P,with superior elastic properties,fea-turing in the ma-triangular-prism bilayers in the crystal *** now,besides Nb 3 As 2 C,the pure phases of the other 321 compounds have not been realized,hampering the study of their intrinsic ***,molten-salt sintering(MSS)and solid-state synthesis(SSS)were applied to synthesize As/P-containing 321 phases and 211 *** the phase composition of the end-product via multiple-phase Rietveld refinement,we found that MSS can effectively improve the purity of P-containing maX phases,with the phase content up to 99%in Nb_(3)P_(2)C and 75.4(5)%in Nb 2 *** contrast,MSS performed poorly on As-containing maX phases,only 8.9(4)%for Nb 3 As 2 C and 64(2)%for Nb 2 AsC,as opposed to the pure phases obtained by *** experimental analyses combined with first-principles calculations reveal that the dominant formation route of Nb_(3)P_(2)C is through NbP+Nb+C→Nb_(3)P_(2)***,we found that the benefits of MSS on P-containing maX phases are on the facilitation of three consid-ered chemical reaction routes,especially on Nb 2 PC+NbP→Nb_(3)P_(2)***,the intrinsic physical properties and Fermi surface topology of two 321 phases consisting of electron,hole,and open orbits are revealed theoretically and experimentally,in which the electron carriers are dominant in electrical *** feasible synthesis methods and the formation mechanism are instructive to obtain high-purity As/P-containing maX phases and explore new maX ***,the intrinsic physical properties will give great support for future applications on 321 phases.

关键词： maX phase Molten-salt synthesis Chemical reaction route Metallic ceramics Formation mechanism Quasi-harmonic approximation

fast local wavenumber （FLW） method for the inversion of magnetic source parameters

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

Applied Geophysics 2018年第2期15卷 353-360,365页

作者： ma Guo-Qing Ming Yan-Bo Han Jiang-Tao Li Li-Li Meng Qing-fa College of Geoexploration Science and Technology Jilin University Changchun China

为磁性的异例的解释的当前的本地 wavenumber 方法由解决复杂矩阵计算地质的身体的地点。一会儿，如此的方法要求知道结构的索引，它是代表来源类型的一个参数。结构的索引是难的在真实数据知道；因而，当前的方法的精确是低的。我们在... 详细信息

为磁性的异例的解释的当前的本地 wavenumber 方法由解决复杂矩阵计算地质的身体的地点。一会儿，如此的方法要求知道结构的索引，它是代表来源类型的一个参数。结构的索引是难的在真实数据知道；因而，当前的方法的精确是低的。我们在场快本地 wavenumber (FLW ) 方法，并且把水平、垂直的本地 wavenumbers 的摆平的和定义为累积本地 wavenumber。FLW 方法是 umulative 本地人 wavenumberand 的线性联合另外的 wavenumbers，并且没有一个 priori 信息和矩阵答案，被用来计算地点和来源的结构的索引。我们把 FLW 方法用于合成磁性的异例，并且结果建议 FLW 方法对背景和倾斜的磁化感觉迟钝。下次，我们把 FLW 方法用于真实磁性的数据获得地点和来源的结构的索引。

关键词：本地 wavenumber 磁性的异例结构的索引

Fundamental studies for high temperature processing of tungsten leaching residues for alloy formation

在线全文

学校读者我要写书评

暂无评论

Tungsten 2020年第4期2卷 362-370页

作者： Xu Wang Xiao‑Dong ma Kun Su Chun‑fa Liao Bao‑Jun Zhao faculty of materials Metallurgy and ChemistryJiangxi University of Science and TechnologyGanzhouChina The University of Queensland BrisbaneAustralia

The first step in the production of tungsten is to enrich tungsten from two minerals wolframite((Fe,Mn)WO_(4))and scheelite(CaWO_(4))through the leaching *** leaching residue usually contains a certain amount(2-5 wt%)of WO_(3) which is higher than that in the tungsten ore(generally less than 1 wt%).In addition,the leaching residue may also consist of other valuable elements such as Cu,Ta,Nb,Sn,Sc,Mn and *** the phases and their compositions present in the residue is one of the key steps for the efficient *** typical residue sample is carefully analysed by electron probe X-ray microanalysis and X-ray fluorescence.A high-temperature process,which includes pre-reduction at 1000-1100℃and smelting reduction at 1450-1500℃,is proposed to efficiently recover the valuable *** work and thermo-dynamic calculations confirmed that most of the valuable elements can be economically recovered with optimum conditions.

关键词： Tungsten Leaching residue Valuable elements Liquidus temperature Slag

Spontaneous remission of Pneumocystisjiroveci pneumonia in 2 non-AIDS immunocompromised patients

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

Chinese Medical Journal 2013年第1期126卷 184-185页

作者： MU Xiang-dong WANG Guang-fa.ma.Jing ZHANG Cheng SU Li CHEN Jian Department of Respiratory Medicine Peking University FirstHospital Beijing 100034 China

Pneumocystis jiroveci （P. jiroveci） pneumonia （PCP） in non-AIDS immunocompromised patients ismuch more critical than that in AIDS patients,1 Without treatment, mortality of PCP in immunocompromised patients approaches 100 percent, and there were no reports of spontaneous remissions of PCP without anti-PCP therapy.2 Here we report 2 non-AIDS immunocompromised patients in whom PCP developed and remitted without treatment.

关键词： Pneumocystis jiroveci pneumonia non-AIDS immunocompromised patients spontaneous remission

Study of endorectal ultrasonography in the staging of rectal cancer

在线全文

学校读者我要写书评

暂无评论

Chinese Medical Journal 2012年第20期125卷 3740-3743页

作者： REN Jun-hong GUO fa-jin DAI Wei-de HAN Xiu-jie ma Na Department of Ultrasound Diagnosis Beijing Hospital of Ministry of HealthBeijing 100730China

Background There is no consensus regarding the performance for endorectal ultrasonography （ERUS） at every stage of rectal cancer. Thus, the purpose of our study was to further assess the value of ERUS in the preoperative staging of rectal cancer. Methods A retrospective study was performed with 44 consecutive patients （mean age：（63.3±10.2） years） who underwent surgical treatment for endorectal carcinoma and were preoperatively evaluated using Biplane ERUS between September 2008 and December 2010. We compared the ERUS staging with the pathological findings based on surgical specimens. Results ERUS staging agreed with the histologic staging in 39 of the 44 （88.6%） patients： the agreement on the depth of transmural invasion was good （k= 0.73; 95% CI： 0.60-0.86, P =0.000）. The detection sensitivities of rectal cancer with ERUS were as follows： T1 85.7%, T2 87.5%, T3 88.9%, and T4 100.0% with specificity values of T1 97.3%, T2 92.9%, T3 96.2%, and T4 97.6%. ERUS correctly staged patients with T1 95.5%, T2 90.9%, T3 70.5 %, and T4 97.7%. The positive predictive value of ERUS was lowest for T4 （75%）, but highest for T3 （94.1%） followed by T2 （87.5%） and T1 （85.7%）; the negative predictive values of ERUS from high to low were ordered as T4 （100%）, T1 （97.3%）, T2 （92.9%）, and T3 （92.6%）. The percentage of total over-staged cases was 4.5% and the under-staged cases was 6.8%. The extent of perirectal lymph node metastases was determined with a sensitivity of 68.4% （13/19）, specificity of 80.0% （20/25）, and diagnostic accuracy of 75.0% （33/44）.

关键词： ultrasonography endoscopic," stage," rectal cancer

计及故障维修与网络重构的灾后配电网综合调度策略

在线全文

学校读者我要写书评

暂无评论

中国电机工程学报 2024年第5期44卷 1764-1776,I0008页

作者：汪涛武传涛随权陈岑马云聪林湘宁李正天魏繁荣强电磁工程与新技术国家重点实验室(华中科技大学) 湖北省武汉市430074

当前,灾后配电网负荷恢复与故障维修多是独立考虑,缺乏有效联动,且没有合理计及包含故障维修时间及新能源出力的不确定性在内的双重因素影响。为此,提出一种灾后配电网维修恢复联合调度策略。首先,提出灾后配电网两阶段求解框架,第一阶... 详细信息

当前,灾后配电网负荷恢复与故障维修多是独立考虑,缺乏有效联动,且没有合理计及包含故障维修时间及新能源出力的不确定性在内的双重因素影响。为此,提出一种灾后配电网维修恢复联合调度策略。首先,提出灾后配电网两阶段求解框架,第一阶段求解故障维修计划及网络重构问题,第二阶段解决移动式储能系统参与下的灾后配电网源荷协同调度问题。其次,构建移动式储能系统与维修人员的调度模型,量化分析移动式储能系统时空转移模型及能量模型,同时基于维修人员的时空转移特性,建立故障维修及网络重构模型。在此基础上,以恢复运行成本最小化为目标,分别采用离散鲁棒与连续鲁棒处理故障维修时间与新能源出力的不确定性,构建灾后配电网综合调度模型。最后,采用改进IEEE 33节点配电网进行仿真测试。结果表明,所提调度策略能够显著降低负荷失电率,减少停电损失。此外,两阶段算法在显著提升求解速度的同时能够保证求解精度,具有可行性和合理性。

关键词：配电网故障维修网络重构移动式储能系统两阶段求解鲁棒优化

维普期刊数据库博看期刊