检索结果-南通市图书馆

International Journal of Minerals,Metallurgy and materials 2024年第9期31卷 2048-2061页

作者： Jirui ma Xiaopeng Lu Santosh Prasad Sah Qianqian Chen You Zhang Fuhui Wang Corrosion and Protection Center Northeastern UniversityShenyang110819China Faculty of engineering Hokkaido UniversityHokkaido 060-8628Japan College of New materials and Chemical engineering Beijing Institute of Petrochemical TechnologyBeijing 102617China

To enhance the long-term corrosion resistance of the plasma electrolytic oxidation(PeO)coating on the magnesium(Mg)alloy,an inorganic salt combined with corrosion inhibitors was used for posttreatment of the *** this study,the corrosion performance of PeO-coated AM50 Mg was significantly improved by loading sodium lauryl sulfonate(SDS)and sodium dodecyl benzene sulf-onate into ba(NO_(3))_(2) post-sealing *** electron microscopy,X-ray photoelectron spectroscopy,X-ray diffraction,Fourier transform infrared spectrometer,and ultraviolet-visible analyses showed that the inhibitors enhanced the incorporation of baO_(2) into PeO *** impedance showed that post-sealing in ba(NO_(3))_(2)/SDS treatment enhanced corrosion resistance by three orders of *** total impedance value remained at 926Ω·cm^(2)after immersing in a 0.5wt%NaCl solution for 768 h.A salt spray test for 40 days did not show any obvious region of corrosion,proving excellent post-sealing by ba(NO_(3))_(2)/SDS *** corrosion resistance of the coating was enhanced through the synergistic effect of baO2 pore sealing and SDS adsorption.

关键词： Mg plasma electrolytic oxidation posttreatment corrosion resistance

management of Acute Bowel Obstruction in Adults in Ziguinchor hospital establishments: About 163 Cases Followed Up

在线全文

学校读者我要写书评

暂无评论

Surgical Science 2024年第4期15卷 207-218页

作者： Omar Sow Cheikh h. badji Mouhamed Dieng Reymond Seydi Aissata Diallo Cheikh Diouf Papa A. ba Boubacar Fall Department of General Surgery Peace Hospital Assane Seck University of Ziguinchor Ziguinchor Senegal Department of General Surgery Central Regional Hospital of Ziguinchor Assane Seck University of Ziguinchor Ziguinchor Senegal Department of General Surgery University of Iba Der Thiam Thies Senegal

Acute intestinal obstruction represents a very frequent admission to surgical emergencies. The aim of our study was to make a descriptive analysis of the management of acute intestinal obstructions at the level of hospital establishments in Ziguinchor. materials and Methods: This was a retrospective, descriptive, multicenter study from the period of January 1, 2017 to December 31, 2021. Patients over 15 years of age admitted for occlusive syndrome in the two surgical departments of the Ziguinchor regional hospitals were included in the study. epidemiological, diagnostic, therapeutic and evolutionary data were studied. Results: Acute intestinal occlusions accounted for 8.3% of admissions. A total of 163 patients were enrolled, 61.9% were men, sex ratio of 1.6. The mean age was 48.7 years. The average consultation time was 74.8 hours (3.12 days). The total occlusive syndrome was in 48.5% of the cases. Abdominal pain was present in 87.1%, vomiting in 74.2%, cessation of matter and gas in 60.7% and meteorism in 36.2%. Biological lab tests reported hyperleukocytosis in 28.1% of the cases. Abdominal CT scans were performed in 71.2%, confirming the diagnosis in 90.5% and determining the etiology in 93.1%. The zone of the obstruction in the small bowel was 62.7%, and in the colon in 37.3%. Functional occlusions accounted for 22.7% of cases and mechanical for 77.3%, including 120 cases of strangulation occlusion (95.2%) and 6 cases of obstruction. etiologies were dominated by adhesions and/or fibrous bands (61.2%). Medical treatment resolved the occlusive syndrome in 9.2% of cases, instrumental treatment in 17.1% and surgical treatment in 77.3%. Adhesiolysis/section of fibrous bands (55.7%), detorsion (14.3%) and resection anastomosis (11.9%) were the most common surgical procedures. Overall morbidity was 11.6%, dominated by surgical site infection (7.14%). The mean resumption of intestinal transit was 2.7 days, and the mean hospital stay was 7.9 days. Overall mortality was

关键词： Intestinal Obstruction emergency Surgery Ziguinchor

Selective butyric acid production from CO_(2)and its upgrade to butanol in microbial electrosynthesis cells

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

environmental Science and ecotechnology 2024年第1期17卷 119-127页

作者： Meritxell Romans-Casas Laura Feliu-Paradeda Michele Tedesco hubertus V.M.hamelers Lluis bañeras M.Dolors balaguer SebastiàPuig Paolo Dessì Institute of the environment University of Girona.Campus MontiliviCarrer Maria Aurélia Capmany 69E-17003GironaSpain Molecular Microbial ecology Group Institute of Aquatic EcologyUniversity of GironaMaria Aurelia Capmany 4017003GironaSpain Wetsus European Centre of Excellence for Sustainable Water TechnologyOostergoweg 98911MALeeuwardenthe Netherlands

Microbial electrosynthesis(MeS)is a promising carbon utilization technology,but the low-value products(i.e.,acetate or methane)and the high electric power demand hinder its industrial *** this study,electrically efficient MeS cells with a low ohmic resistance of 15.7 mU m^(2)were operated galvanostatically in fed-batch mode,alternating periods of high CO_(2)and h2 *** promoted acetic acid and ethanol production,ultimately triggering selective(78%on a carbon basis)butyric acid production via chain *** average production rate of 14.5 g m^(-2)d^(-1)was obtained at an applied current of 1.0 or 1.5 ma cm^(-2),being Megasphaera *** key chain elongating *** a second cell with the catholyte containing the enriched community resulted in butyric acid production at the same rate as the previous cell,but the lag phase was reduced by 82%.Furthermore,interrupting the CO_(2)feeding and setting a constant ph2 of 1.7e1.8 atm in the cathode compartment triggered solventogenic butanol production at a ph below *** efficient cell design resulted in average cell voltages of 2.6e2.8 V and a remarkably low electric energy requirement of 34.6 kWhel kg1 of butyric acid produced,despite coulombic efficiencies being restricted to 45%due to the cross-over of O_(2)and h2 through the *** conclusion,this study revealed the optimal operating conditions to achieve energy-efficient butyric acid production from CO_(2)and suggested a strategy to further upgrade it to valuable butanol.

关键词： Biocathode Bioelectrochemical system Chain elongation hydrogen partial pressure Megasphaera

摩尔比对MMOS水泥力学性能和变形行为的影响及机理

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

建筑材料学报 2024年第8期27卷 733-743页

作者：巴明芳马哲洋纪璐鑫崔嘉铭柳俊哲宁波大学土木工程与地理环境学院浙江宁波315211 青岛农业大学建筑工程学院山东青岛266109

研究了原材料摩尔比(n(MgO)∶n(MgSO_(4))∶n(h_(2)O))对改性硫氧镁(MMOS)水泥力学性能和变形行为的影响,并采用X射线衍射仪(XRD)、扫描电镜(SeM)、傅里叶变换红外光谱(FTIR)及热重分析(TG)等测试技术对其机理进行分析.结果表明:MMOS水... 详细信息

研究了原材料摩尔比(n(MgO)∶n(MgSO_(4))∶n(h_(2)O))对改性硫氧镁(MMOS)水泥力学性能和变形行为的影响,并采用X射线衍射仪(XRD)、扫描电镜(SeM)、傅里叶变换红外光谱(FTIR)及热重分析(TG)等测试技术对其机理进行分析.结果表明:MMOS水泥的抗压强度和抗折强度随着水硫比和氧硫比的提高均呈提升趋势.其中原材料摩尔比为10∶1∶12时,水泥力学性能最优.不同摩尔比MMOS水泥在56d龄期内均呈膨胀变形,其中总变形随水硫比和氧硫比的提高呈减小趋势;自收缩变形随水硫比的提高而减小,随氧硫比的提高呈先增后减趋势.这主要是由于硬化后不同摩尔比MMOS水泥中的水化产物Mg(Oh)_(2)和5·1·7相(5Mg(Oh)_(2)·MgSO_(4)·7h_(2)O)含量各有不同.当Mg(Oh)_(2)含量减少,而5·1·7相含量增加时,MMOS水泥的膨胀变形量降低,同时其抗折强度和抗压强度有所提升.

关键词：摩尔比改性硫氧镁水泥力学性能体积变形机理分析

高选择性h_(2)O_(2)光合成:ba原子注入面内高度有序结晶结构的g-C_(3)N_(4)纳米棒

在线全文

学校读者我要写书评

暂无评论

Chinese Journal of Catalysis 2024年第5期60卷 231-241页

作者：孟爱云马辛源温达钟威周双苏耀荣深圳技术大学新材料与新能源学院广东深圳518118

过氧化氢(h_(2)O_(2))是一种重要的绿色氧化剂,在医疗、军工、食品和绿色化学合成等领域有着广泛应用.然而,传统蒽醌法合成h_(2)O_(2)存在能耗高、污染严重等问题.光催化合成h_(2)O_(2)技术,利用来源丰富的太阳能实现氧气的两电子还原,... 详细信息

过氧化氢(h_(2)O_(2))是一种重要的绿色氧化剂,在医疗、军工、食品和绿色化学合成等领域有着广泛应用.然而,传统蒽醌法合成h_(2)O_(2)存在能耗高、污染严重等问题.光催化合成h_(2)O_(2)技术,利用来源丰富的太阳能实现氧气的两电子还原,被认为是替代蒽醌工艺的理想方案.石墨相氮化碳(g-C_(3)N_(4))因具有成本低、化学性质稳定和电子结构易调等优点,在光催化合成h_(2)O_(2)方面展现出很大潜力.但传统g-C_(3)N_(4)的面内结晶度低,且对两电子氧还原反应的选择性差,这极大地限制了其光合成h_(2)O_(2)效率.为解决这一难题,本文合理设计了一种新策略:将钡(ba)原子注入面内高度有序结晶结构的g-C_(3)N_(4)纳米棒(BI-CN),在增强g-C_(3)N_(4)的面内结晶度的同时,进一步提高其对两电子氧还原反应的选择性.本文采用baCl2诱导的面内聚合策略,实现了ba原子注入的面内高度有序结晶结构g-C_(3)N_(4)纳米棒的可控合成.在合成过程中,三聚氰胺分子选择性地吸附在baCl2的(200)晶面,并与暴露在baCl2表面的ba原子形成ba-N键.这种强相互作用诱导了三嗪结构单元的定向富集和聚合,从而形成面内有序结晶结构的g-C_(3)N_(4)结构.同时,ba原子通过ba-N键稳定地锚定在g-C_(3)N_(4)结构中,构建了ba原子注入的面内高度有序结晶结构的g-C_(3)N_(4)纳米棒.实验和理论计算结果表明,由于ba原子和N原子的电负性差异,电子从ba原子迁移到N原子,形成缺电子的ba活性位点.注入的ba原子起到正电荷中心的作用,氧气分子以Pauling构型稳定地吸附在ba原子上,该吸附构型使得O-O键不易断裂并增强了*OOh中间体的稳定性,从而抑制了四电子氧还原生成水的反应,有效地提高了两电子氧还原的选择性,最终实现高效的光催化h_(2)O_(2)合成.其中,最优的BI-CN3(三聚氰胺和baCl2质量比为9:2)光催化生成h_(2)O_(2)的速率达到353μmol L^(-1) h^(-1),是原始g-C_(3)N_(4)的6.1倍,且表现出良好的光催化循环使用性能.同时,BI-CN3光催化剂表现出更强的表面光电压信号、光电流信号以及更低的荧光强度,表明其具有更强的光生电荷分离和迁移效率.综上,本文不仅为构建具有面内高结晶度和原子级活性位点的g-C_(3)N_(4)光催化剂提供了一种新策略,还为提高两电子氧还原反应的选择性提供了新思路,可为光催化h_(2)O_(2)的高效、绿色合成提供了参考.

关键词： h_(2)O_(2)光合成石墨相氮化碳 ba原子注入高选择性两电子氧还原面内高结晶度

Correlation of work function and stacking fault energy through Kelvin probe force microscopy and nanohardness in diluteα-magnesium

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 magnesium and Alloys 2024年第1期12卷 237-250页

作者： Yigit Türe Ali Arslan Kaya hüseyin Aydin Jiang Peng Servet Turan eskisehir Technical University Porsuk Vocational SchoolElectronics and Automation DepartmentProgram of MechatronicsEskisehirTurkey Mugla Sitki Kocman University Engineering FacultyMetallurgy and Materials Engineering DepartmentMuglaTurkey hüseying Aydın TUBITAK MRCTurkey Jiang Peng Chongqing UniversityChina eskisehir Technical University Engineering FacultyMaterials Science and Engineering DepartmentEskisehirTurkey

electronic interactions of the Group 2A elements with magnesium have been studied through the dilute solid solutions in binary Mg-Ca,Mg-Sr and Mg-ba *** investigation incorporated the difference in the‘Work Function'(ΔWF)measured via Kelvin Probe Force Microscopy(KPFM),as a property directly affected by interatomic bond types,*** electronic structure,nanoindentation measurements,and Stacking Fault energy values reported in the *** was shown that the nano-hardness of the solid-solutionα-Mg phase changed in the order of Mg-Ca>Mg-Sr>***,it was shown,by also considering the nano-hardness levels,that SFe of a solid-solution is closely correlated with its‘Work Function'***-hardness measurements on the eutectics andΔWF difference between eutectic phases enabled an assessment of the relative bond strength and the pertinent electronic structures of the eutectics in the three *** withΔWF and at least qualitative verification of those computed SFe values with some experimental measurement techniques were considered important as those computational methods are based on zero Kelvin degree,relatively simple atomic models and a number of *** asserted by this investigation,if the results of measurement techniques can be qualitatively correlated with those of the computational methods,it can be possible to evaluate the electronic structures in alloys,starting from binary systems,going to ternary and then multi-elemental *** investigation has shown that such a qualitative correlation is *** all,the SFe values are not treated as absolute values but rather become essential in comparative investigations when assessing the influences of alloying elements at a fundamental level,that is,free electron density *** study indicated that the principles of‘electronic metallurgy'in developing multi-elemental alloy systems can be followed via practical experimental methods,i.e.ΔWF measurements using KPF

关键词： Mg alloys Dilute alloys Work function Stacking fault energy Kelvin probe force microscopy Short range order Miedema Nanoindentation eutectics

Influence of erbium on structural,and charged particles,photons,and neutrons shielding properties of ba_(1-x)er_(x)SnO_(3) perovskite ceramics

在线全文

学校读者我要写书评

暂无评论

Journal of Rare earths 2024年第4期42卷 724-732页

作者： M.K.h.hamad Nidal Dwaikat M.h.A.Mhareb M.I.Sayyed R.M.hamad Y.S.M.Alajerami M.A.Almessiere Gameel Saleh Ahmad hussein Alomari K.A.Ziq Department of basic Sciences School of Social and Basics SciencesAl Hussein Technical UniversityKing Abdullah II St 242Amman11831Jordan Department of Physics College of Engineering and PhysicsInterdisciplinary Research Center for Advanced MaterialsKing Fahd University of Petroleum&MineralsDhahran31261Saudi Arabia Department of Physics College of ScienceImam Abdulrahman Bin Faisal UniversityP.O.Box 1982Dammam31441Saudi Arabia basic and Applied Scientific Research Center Imam Abdulrahman Bin Faisal UniversityP0.Box 1982Dammam31441Saudi Arabia Department of Physics Faculty of ScienceIsra UniversityAmman11622Jordan Department of Nuclear Medicine Research Institute for Research and Medical Consultations(IRMC)Imam Abdulrahman Bin Faisal UniversityPo.Box 1982Dammam31441Saudi Arabia Medical Imaging Department Applied Medical Sciences FacultyAl Azhar University-Gaza CityPo.Box 1277Palestine Department of Biophysics Institute for Research and Medical Consultations(IRMC)Imam Abdulrahman Bin Faisal UniversityPo.Box1982Dammam 31441Saudi Arabia Department of Biomedical engineering College of EngineeringImam Abdulrahman Bin Faisal UniversityPo.Box 1982Dammam31441Saudi energy&Minerals Regulatory Commission Amman11821Jordan

Five perovskite ceramics samples of ba_(1-x)er_(x)SnO_(3) with x=0.00,0.05,0.10,0.15,and 0.20 were synthesized using the conventional solid-state reaction *** prepared samples were characterized by X-ray diffraction(XRD),Fourier transforms infrared(FTIR),and UV-Vis *** shielding properties against ionizing radiation were also *** XRD analysis shows the perovskite cubic structure as the major phase in all *** FTIR reveals a distinctive band around 614-620 cm^(-1) ascribed to the antisymmetric O-Sn-O ***-Vis spectroscopy was used to determine the bandgap according to diffuse reflectance,and the results display a fixed enhancement in the bandgap from 3.2 to 3.3 eV for all ***-ray shielding properties of the synthesized samples were experimentally measured and compared with XCOM computational *** relative differences(Δ,%)between experimental and theo retical values are low and fall within the 0.446%-7.10%*** addition of er leads to the enhanced density,neutron,and gamma shielding *** contrast,charged particles’shielding parameters gradually reduce with rising er *** results suggest that ba_(1-x)er_(x)SnO_(3) samples can be used in different radiation shielding applications.

关键词： Perovskite Ceramics Gamma ray shielding mass stopping power Rare earths

Mineralogy,M-type tetrad effect and radioactivity of altered granites at the *** Garadi shear zone,central eastern Desert,egypt

在线全文

学校读者我要写书评

暂无评论

Chinese Journal Of Geochemistry 2011年第2期30卷 153-164页

作者： el Nahas h.A. el Feky M.G. Mira h. Nuclear materials Authority P.O. Box 530 Cairo Egypt

The G. Abu Garadi area is covered mainly by metasediments, alkali feldspar granites and stream sediments. The alkali feldspar granite is traversed by a major strike-slip fault trending in an N-S direction as well as two subordinate sets of faults trending NW to WNW for the first one and Ne for the second one. These faults represent the shear zones affected by magmatic (syngenetic) as well as hydrothermal (epigenetic) activities causing alteration of the granitic rocks. The most common alteration features are albitization, greisenization and koalinitization. The mass balance calculations of the studied altered samples show enrichments in Zr, Y, Ni, U, Th and Ga and depletions in Zn, Sr, Nb, ba, Pb, Cu and V. Only the greisenized samples exhibit a significant enrichment in Nb, ∑Ree budget and pronounced lanthanide tetrad effect (M-type), especially Te1,4, while weakly expressed tetrad effects are for the other albitized and koalinitized samples. Mineralogically, the common accessory minerals in the altered samples include samarskite-(Y), betafite, uranothorite, zircon, fluorite and cassiterite. The greisenized granites contain high eU and eTh than the other altered types, where they are characterized by an assemblage of the radioactive minerals; samarskite-(Y), betafite, uranothorite in addition to zircon. The inter-element relationships between U and Th and also their ratios illustrate that the radioelement distribution in these granites is mainly governed by magmatic processes, in addition to post-magmatic ones. The distribution of chemical elements and the fractionation of some isovalents within the shear zone are largely controlled by the newly formed mineral phases. With respect to uranium mobilization, uranium migrated from the host alkali feldspar granites of G. Abu Garadi, while the shear zones acted as traps for the migrated uranium. Moreover, U migrated in the shear zone during greisenization and albitization, and migrated out during koalinitization.

关键词： M 类型四个效果改变的花岗石 G。Abu Garadi 砍地区中央东方沙漠埃及

在线全文

学校读者我要写书评

暂无评论

鳞片仿生制动盘散热性能研究

机械工程学报 2024年第6期60卷 354-362页

作者：周素霞巴馨悦王君艳李光曲直北京建筑大学机电与车辆工程学院北京100044 北京建筑大学城市轨道交通车辆服役性能保障北京市重点实验室北京100044

制动技术是影响列车提速的重要因素,制动盘散热能力是提高高速列车运行速度的重要参数。为了从结构上改善制动盘的散热能力,降低制动盘工作温度和热应力,结合仿生学,以鳞片为仿生原型,设计两种具有新结构的仿生制动盘。对比传统直辐板... 详细信息

制动技术是影响列车提速的重要因素,制动盘散热能力是提高高速列车运行速度的重要参数。为了从结构上改善制动盘的散热能力,降低制动盘工作温度和热应力,结合仿生学,以鳞片为仿生原型,设计两种具有新结构的仿生制动盘。对比传统直辐板制动盘,使用流体仿真软件模拟不同制动盘内流场情况,进而采用热机耦合方法,计算300 km/h初速度一次紧急制动工况下的制动盘温度及热应力结果。结果表明,新型鳞片仿生制动盘能加速制动盘内空气流通,提高制动过程中的对流换热系数;并降低制动盘的工作温度以及热应力,在一定程度上减小热载荷对于制动盘的影响。

关键词：高速列车盘型制动仿生学鳞片结构

神经内镜手术治疗高血压脑出血破入脑室的临床效果分析

在线全文

学校读者我要写书评

暂无评论

中国实用医药 2024年第16期19卷 48-51页

作者：丹巴高娃兴安盟人民医院 137400 兴安盟乌兰浩特市都林社区卫生服务中心内科 137400

目的观察高血压脑出血(hICh)破入脑室经神经内镜手术治疗的效果。方法选取hICh破入脑室患者70例,随机分为观察组(经神经内镜手术治疗)与对照组(经常规显微镜下手术治疗),各35例。对比两组血肿清除情况、临床指标、并发症发生情况、美国... 详细信息

目的观察高血压脑出血(hICh)破入脑室经神经内镜手术治疗的效果。方法选取hICh破入脑室患者70例,随机分为观察组(经神经内镜手术治疗)与对照组(经常规显微镜下手术治疗),各35例。对比两组血肿清除情况、临床指标、并发症发生情况、美国国立卫生研究院卒中量表(NIhSS)评分、barthel指数、预后情况。结果观察组患者术后1、3、7 d脑室内血肿清除率分别为(59.3±9.7)%、(71.2±15.5)%、(84.4±7.7)%,均高于对照组的(26.4±10.0)%、(51.1±14.4)%、(64.2±8.8)%(P0.05)。观察组手术时间为(1.5±0.1)h、出血量为(38.3±4.7)ml、引流时间为(3.6±1.4)d,对照组手术时间为(2.6±0.4)h、出血量为(46.1±5.8)ml、引流时间为(6.1±1.0)d。观察组手术时间、引流时间短于对照组,出血量少于对照组(PhSS评分为(14.9±2.2)分、barthel指数为(49.5±3.9)分,对照组NIhSS评分为(18.7±3.7)分、barthel指数为(43.7±2.9)分,观察组NIhSS评分低于对照组,barthel指数高于对照组(PhICh破入脑室患者脑室内血肿清除率,改善预后,并发症较少,价值较高。

关键词：高血压脑出血破入脑室并发症神经内镜血肿清除率预后临床指标