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effects of cowpea(Vigna unguiculata) root mucilage on microbial community response and capacity for phenanthrene remediation

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Journal of environmental Sciences 2015年第7期27卷 45-59页

作者： Ran Sun Richard W.Belcher Jianqiang Liang Li Wang Brian Thater David e.Crowley Gehong Wei State Key Laboratory of Crop Stress Biology in Arid Areas College of Life Sciences Northwest A&F University Department of environmental Sciences University of California at Riverside

Biodegradation of polycyclic aromatic hydrocarbons（PAHs） is normally limited by their low solubility and poor bioavailability. Prior research suggests that biosurfactants are synthesized as intermediates during the production of mucilage at the root tip. To date the effects of mucilage on PAH degradation and microbial community response have not been directly examined. To address this question, our research compared 3 cowpea breeding lines（Vigna unguiculata） that differed in mucilage production for their effects on phenanthrene（PHe） degradation in soil. The High Performance Liquid Chromatography results indicated that the highest PHe degradation rate was achieved in soils planted with mucilage producing cowpea line C1, inoculated with Bradyrhizobium, leading to 91.6% PHe disappearance in 5 weeks. In root printing tests, strings treated with mucilage and bacteria produced larger clearing zones than those produced on mucilage treated strings with no bacteria or bacteria inoculated strings. experiments with14C-PHe and purified mucilage in soil slurry confirmed that the root mucilage significantly enhanced PHe mineralization（82.7%）, which is 12% more than the control treatment without mucilage. The profiles of the PHe degraders generated by Denaturing gradient gel electrophoresis suggested that cowpea C1, producing a high amount of root mucilage, selectively enriched the PHe degrading bacteria population in rhizosphere. These findings indicate that root mucilage may play a significant role in enhancing PHe degradation and suggests that differences in mucilage production may be an important criterion for selection of the best plant species for use in phytoremediation of PAH contaminated soils.

关键词： Bioremediation Mucilage Phytoremediation PAH mineralization Rhizosphere

Auger Depth Profiling of Carbonized SiC/Si Samples

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Journal of Materials Science & Technology 1997年第6期13卷 499-502页

作者： Shahzad Naseem and Shazia Yasin(Centre for Solid State Pliysics, University of the Punjab, Quaid-e-Azam Campus, Lahore-54590, Pakistan) Centre for Solid State Physics University of the Punjab Quaid-e-Azam Campus Lahore-54590 Pakistan Microelectronics Research Centre Cavendish Lab. University of Cambridge Madingley Road Cambridge CB3 OHE United Kingdom

Silicon carbide (SiC) has been prepared by passing natural gas over (100) oriented hot Si substrate at different temperatures in the range 930~1000℃. Reaction times of 60 and 90 min are *** profile, using Auger electron Spectroscopy, shows the formation of SiC under a thin coating of carbon for the samples prepared at 930 and 950℃. Annealing, at 1050℃ for 12 h,results in a more pronounced formation of SiC. It is found that at the temperature of 1000℃and reaction times of 60 and 90 min, a hard diamond-like coating is formed.

关键词： SiC Auger Depth Profiling of Carbonized SiC/Si Samples

缺血性脑卒中单侧上肢瘫痪个体化影像学分析2例

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中国临床医学影像杂志 2024年第9期35卷 669-671页

作者：郝蓉蓉宋蕾贾卫华马燕红袁永娥陈星张华北京中医药大学东直门医院脑病一科北京100700 北京市石景山区五里坨社区卫生服务中心中医科北京100042

偏瘫是缺血性脑卒中较为常见的临床表现,仅出现上肢或下肢运动障碍的单侧肢体瘫痪相对少见[1-2]。弥散张量成像(DTI)和由DTI衍生的纤维示踪技术(DTT)可准确且无创性地评估缺血性脑卒中患者锥体束的损伤情况,使得精准描述缺血性脑卒中患... 详细信息

偏瘫是缺血性脑卒中较为常见的临床表现,仅出现上肢或下肢运动障碍的单侧肢体瘫痪相对少见[1-2]。弥散张量成像(DTI)和由DTI衍生的纤维示踪技术(DTT)可准确且无创性地评估缺血性脑卒中患者锥体束的损伤情况,使得精准描述缺血性脑卒中患者责任病灶对锥体束的影响成为现实[3]。

关键词：缺血性卒中麻痹磁共振成像

共振光泵X射线激光的抽运谱线和吸收谱线波长匹配实验

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物理学报 1996年第2期45卷 205-209页

作者：范品忠 e.FILL 中国科学院上海光学精密机械研究所 Max-Planck-Institut fur Quantenoptik Garching85748 Germany

用octadecyl hydrogen maleate(OHM)晶体谱仪进行了4.5nm附近如下三组共振光泵X射线激光的抽运谱线和吸收谱线对波长匹配实验研究:SiXⅡ3d—2p,4.4021nm,MgX2s—4p,4.4050nm;CuXIX4f—3d, 4.7329nm,MgX2p—4d,4.7310nm;和AIXI3p—2s,4.8... 详细信息

关键词： X射线激光抽运谱线吸收谱线波长匹配

Hydrothermal Characteristics of Blended Cement Pastes Containing Silica Sand Using Cement Kiln Dust as an Activator

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Journal of Materials Science & Technology 2002年第5期18卷 474-478页

作者： S.A.Abo-el-enein F.I.el-Hosiny e.el-Shimy T.A.Osman Faculty of Sci. Ain Shams Univ. Abbassia-Cairo Egypt Building Res. Cent. P. O. Box 1770 Cairo Egypt

The hydrothermal reactivity of silica sand was studied using cement kiln dust (CKD) as an activator in addition to the Portland cement fraction of el-Karnak cement (a blend of ordinary Portland cement and ground sand). Autoclaved eI-Karnak cement pastes were studied at pressures of 0.507, 1.013 and 1.520 MPa of saturated steam with respect to their compressive strength, kinetics of hydrothermal reaction and the phase composition of the formed hydrates. The role of CKD in affecting the physicochemical and mechanical properties of eI-Karnak cement pastes was studied by autoclaving of several pastes containing 5, 7.5, 10 and 20% CKD at a pressure of 1.013 MPa of saturated steam. CKD was added either as a raw CKD (unwashed) or after washing with water (washed CKD). The results of these physicochemical studies obtained could be related as much as possible to the role of CKD (raw or washed) in affecting the hydrothermal reactivity of silica sand in eI-Karnak cement pastes.

关键词： Blended cement Silica Cement kiln dust Hydrothermal characteristics

Comparative outcomes of Inferior Vena Cava filters placed at bedside using digital radiography versus conventional fluoroscopy

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Journal of Interventional Medicine 2021年第3期4卷 139-142页

作者： John A.Walker Matthew Milam Jorge e.Lopera Department of Radiology University of Texas Health Science Center at San AntonioTexasUSA Department of Medicine Massachusetts General HospitalBostonMAUSA

Purpose:To retrospectively assess the outcomes of Inferior Vena Cava(IVC)filters placed in critically ill patients in the ICU at bedside using digital radiograph(DR)guidance with previous cross-sectional imaging for planning,compared to IVC filters placed by conventional fluoroscopy(CF).Method and materials:The cohort consisted of 129 IVC filter placements;48 placed at bedside and 81 placed conventionally from July 2015 to September *** demographics,indication,radiation exposures,access site,procedural duration,dwell time,and complications were identified by the *** Filter positioning with measurements of tip to renal vein distance and lateral filter tilt were performed when cavograms or post placement CTs were available for *** analysis was performed using Stata IC ***:Technical success of the procedure was 100% in both *** duration was longer at the bedside lasting 14.5+/-10.2 versus 6.7+/-6.0 min(pe bedside DR group had a median radiation exposure of 25 mGy(15-35)and the CF group had mean radiation exposure of 256.94 mGy+/-*** was no significant difference in distance of IVC tip to renal vein(p=0.31),mispositioning(p=0.59),degree of filter tilt(p=0.33),or rate of complications(p=0.65)between the two ***:IVCF placement at the bedside using DR is comparable to CF with no statistical difference in outcomes based on IVCF positioning,degree of lateral tilt or removal *** decreased radiation dose,but with overall increased procedural time.

关键词： Inferior vena cava filters Pulmonary embolism Deep venous thrombosis

中国六省市中小学生电子屏幕使用与近视的关联

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中国学校卫生 2024年第6期45卷 882-886页

作者：高若伊许惠玉罗慧娟张京舒李婷邝惠宁鄂博然郭欣首都医科大学公共卫生学院北京100069 北京市疾病预防控制中心学校卫生所北京市通州区疾病预防控制中心学校卫生科

目的探讨中国六省市中小学生电子屏幕使用情况及其与近视的关联,为综合防控中小学生近视提供科学依据。方法于2020年11月至2022年6月,采用分层整群随机抽样与概率抽样相结合的方法,选取中国六省市(北京市、辽宁省、浙江省、河南省、陕... 详细信息

目的探讨中国六省市中小学生电子屏幕使用情况及其与近视的关联,为综合防控中小学生近视提供科学依据。方法于2020年11月至2022年6月,采用分层整群随机抽样与概率抽样相结合的方法,选取中国六省市(北京市、辽宁省、浙江省、河南省、陕西省、重庆市)16557名中小学生作为研究对象,采用北京市疾病预防控制中心编制的问卷进行电子屏幕使用情况调查,并依据《儿童青少年近视筛查规范》采用质量浓度0.5%的复方托吡卡胺滴眼液麻痹睫状肌后进行裂隙灯验光检查。采用χ^(2)检验比较组间差异,采用二元Logistic回归分析电子屏幕使用与近视的关联。结果有58.3%的中小学生平均每日使用电子屏幕时间≥2 h,有63.4%的中小学生非学习目的一次持续使用电子产品≥15 min。调整混杂因素后,父母不限制使用电子屏幕时间、每日使用电子屏幕时间≥2 h与中小学生近视发生均呈正相关(OR值分别为1.27,1.13,P值均<0.05)。按性别分层分析结果显示,每日电子屏幕使用时间≥2 h的男生发生近视的风险较高(OR=1.15,P<0.05);按年级分层分析结果显示,在小学低年级学生中,父母不限制电子屏幕使用时间和每日电子屏幕使用时间≥2 h与中小学生近视发生均呈正相关(OR值分别为1.34,1.18);在小学高年级学生中,非学习目的一次持续使用电子屏幕时间≥15 min与近视发生呈正相关(OR=1.18)(P值均<0.05)。电子屏幕使用总时间和一次持续使用电子屏幕时间存在相乘交互作用(OR=1.04,P<0.05)。结论中国六省市中小学生电子屏幕使用较多,且电子屏幕使用过多与近视相关。学校和家长应当共同限制中小学生电子屏幕的使用,减少中小学生近视的发生。

关键词：注视眼工具使用行为近视回归分析学生

Tunable bandgaps and flat bands in twisted bilayer biphenylene carbon

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Chinese Physics B 2021年第7期30卷 451-455页

作者： Ya-Bin Ma Tao Ouyang Yuan-Ping Chen Yue-e Xie School of Physics and Optoelectronics Xiangtan UniversityXiangtan 411105China Faculty of Science Jiangsu UniversityZhenjiang 212013China

Owing to the interaction between the layers,the twisted bilayer two-dimensional(2 D)materials exhibit numerous unique optical and electronic properties different from the monolayer counterpart,and have attracted tremendous interests in current physical research *** means of first-principles and tight-binding model calculations,the electronic properties of twisted bilayer biphenylene carbon(BPC)are systematically investigated in this *** results indicate that the effect of twist will not only leads to a phase transition from semiconductor to metal,but also an adjustable band gap in BPC(0 me V to 120 me V depending on the twist angle).Moreover,unlike the twisted bilayer graphene(TBG),the flat bands in twisted BPC are no longer restricted by"magic angles",i.e.,abnormal flat bands could be appeared as well at several specific large angles in addition to the small *** charge density of these flat bands possesses different local modes,indicating that they might be derived from different stacked modes and host different *** exotic physical properties presented in this work foreshow twisted BPC a promising material for the application of terahertz and infrared photodetectors and the exploration of strong correlation.

关键词： twisted bilayer biphenylene carbon adjustable band gap flat bands

Inter-relationship of Various Results in Analysis of （14.0 MeV／U） Pb＋Pb Reaction Using Mica and CN-85 Track Detectors

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Chinese Physics Letters 2005年第1期22卷 69-71页

作者： F.N.Khattak e.U.Khan TabassumNasir J.J.Baluch F.U.Khan U.W.C. GomalUniversityDeraIsmailKhanPakistan RadiationPhysicsDivision PINSTECHNiloreIslamabadPakistan DepartmentofPhysics GomalUniversityDeraIsmailKhanPakistan

Two detector materials mica and cellulose-nitrate(CN)-85 have been used to study (14.0MeV/u) Pb + Pb reaction. events of different multiplicities were registered in mica and CN-85 detectors using the 2π-geometry technique of solid state nuclear track detection. After removing the target material from the detectors the damaged trails in the detectors were revealed as tracks by proper chemical etching. The irradiated area of each sample was scanned and events of different multiplicities were traced. The binary events were bifurcated into elastic and inelastic events. The elastic binary events and three prong events, observed in the reaction, have been used to search out coefficients Cμν in the presence of both the detectors, for the reaction under study. Using these coefficients 3- and 4-prong events have been analysed. From the detailed analysis of the results of (14.0MeV/u) Pb+Pb reaction, obtained from mica and CN-85 track detectors we observed a great resemblance of results obtained from the two detectors. Combining the results of both the detectors, we report some important outcomes.

关键词： CN-85轨迹探测器高能物理学铅原子碰撞反应固态