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Journal of Environmental Sciences 2011年第4期23卷 568-574页

作者： Huiqiang Li Hongjun Han Maoan du wei Wang State Key Laboratory of Urban Water Resources and Environment Harbin Institute of Technology Harbin 150090 China.

Moving bed biofilm reactor （MBBR） was used to treat real coal gasification wastewater. Nitrification of the MBBR was inhibited almost completely during start-up period. Sudden increase of influent total NH 3 concentration was the main factor inducing nitrification inhibition. Increasing DO concentration in the bulk liquid （from 2 to 3 mg/L） had little effect on nitrification recovery. Nitrification of the MBBR recovered partially by the addition of nitrifying sludge into the reactor and almost ceased within 5 days. Nitrification ratio of the MBBR achieved 65% within 12 days by increasing dilute ratio of the influent wastewater with tap water. The ratio of nitrification decreased to 25% when influent COD concentration increased from 650 to 1000 mg/L after nitrification recovery and recovered 70% for another 4 days.

关键词： moving bed biofilm reactor coal gasification wastewater nitrification inhibition nitrification recovery

Formation of macroporous gel morphology by phase separation in the silica sol-gel system containing nonionic surfactant

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Journal of University of Science and Technology Beijing 2005年第6期12卷 564-571页

作者： Junsheng Wu Xiaogang Li wei du Hua Chen Materials Science and Engineering School University of Science and Technology Beijing Beijing 100083 China

The phase separation and gel formation behavior in an alkoxy-derived silica sol-gel system containing C16EO15 has been investigated. Various gel morphologies similar to other sol-gel systems containing organic additives were obtained by changing the preparation conditions. Micrometer-range interconnected porous gels were obtained by freezing transitional structures of phase separation in the sol-gel process. The dependence of the resulting gel morphology on several important reaction parameters such as the starting composition, reaction temperature and acid catalyst concentration was studied in detail. The experimental results indicate that the gel morphology is mainly determined by the time relation between the onset of phase separation and gel formation.

关键词： silica sol-gel phase separation macroporous gel morphology nonionic surfactant

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陕西省土壤无机碳的时空分布特征及影响因素

中国农业科学 2024年第8期57卷 1517-1532页

作者：冯晓琳张楚天许晨阳耿增超胡斐南杜伟西北农林科技大学资源环境学院西北农林科技大学西北农业农村部植物营养与农业环境重点实验室西北农林科技大学黄土高原土壤侵蚀与旱地农业国家重点实验室中国科学院水利部水土保持研究所

【目的】土壤无机碳对于调节全球碳循环有重要作用，然而我国区域尺度上土壤无机碳的分布特征及影响因素尚不明确。对陕西省土壤无机碳时空分布和关键影响因子进行研究可为明确无机碳在陆地生态系统碳循环中的作用和地位提供参考和依据... 详细信息

【目的】土壤无机碳对于调节全球碳循环有重要作用，然而我国区域尺度上土壤无机碳的分布特征及影响因素尚不明确。对陕西省土壤无机碳时空分布和关键影响因子进行研究可为明确无机碳在陆地生态系统碳循环中的作用和地位提供参考和依据。【方法】收集陕西省1980s和2010s两期的65个和142个土壤样本以及相关的地形因素、气候条件、土地利用类型、植被状况和土壤性质数据，采用方差分析和随机森林（Random Forest,RF）模型分析土壤无机碳含量的时间和空间分布特征，并探讨土壤无机碳含量变化的影响因素。【结果】陕西省1980s各区域的土壤无机碳含量表现为：陕北>关中>陕南；与1980s相比，2010s陕北土壤无机碳含量下降了31.5%，关中地区基本保持不变，陕南小幅度上升。1980s到2010s,0—100 cm剖面上不同土层无机碳含量的降幅范围为20.6%—27.7%，其中以0—20和80—100cm土层降幅最大。随机森林模型分析表明，年平均降水量、容重、pH是影响1980s和2010s土壤无机碳含量变化的重要因素，在年平均降水量450—650 mm时土壤无机碳含量最高；土壤无机碳含量随着pH的增加而增加；低容重土壤无机碳含量高于高容重土壤。【结论】总体来看，陕西省土壤无机碳含量呈现从北向南逐渐降低的趋势。与1980s相比，2010s陕西省表层土壤和陕北地区整个土壤剖面无机碳含量显著下降，1980s和2010s陕西省土壤无机碳含量主要受年平均降水量、pH、容重的调控。

关键词：土壤无机碳时空分布随机森林模型陕西省

Monitoring Changes in Hepatic Venous Velocities Flow after a Fluid Challenge Can Identify Shock Patients Who Lack Fluid Responsiveness

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Chinese Medical Journal 2017年第10期130卷 1202-1210页

作者： wei du Xiao-Ting Wang Yun Long Da-wei Liu Department of Critical Care Medicine Peking Union Medical College Hospital Peking Union Medical College Chinese Academy of Medical Sciences Beijing 100730 China

Background： Evaluating the hemodynamic status and predicting fluid responsiveness are important in critical ultrasound assessment of shock patients. Transthoracic echocardiography with noninvasive diagnostic parameters allows the assessment of volume responsiveness. This study aimed to assess tile hemodynamic changes in the liver and systemic hemodynamic changes during fluid challenge and during passive leg raising （PLR） by measuring hepatic venous flow （HVF） velocity. Methods： This is an open-label study in a tertiary teaching hospital. Shock patients with hypoperfusion who required fluid challenge were selected for the study. Patients 〈l 8 years old and those with contraindications to PLR were excluded from the study. Baseline values were measured, PLR tests were performed, and 500 ml of saline was infused over 30 rain. Parameters associated with cardiac output （CO） in the left ventricular outflow tract were measured using the Doppler method. In addition, HVF velocity and right ventricular function parameters were determined. Results： Middle hepatic venous （MHV） S-wave velocity was positively correlated in all patients with CO at baseline （r= 0.706, P〈 0.01 ） and after volume expansion （r= 0.524, P = 0.003）. CO was also significantly correlated with MHV S-wave velocity in responders （r = 0.608, P 〈 0.01）. during PLR, however, hepatic venous S-wave velocity did not correlate with CO. For the parameter AMHV D （increase in change in MHV D-wave velocity after volume expansion）, defined as （MHV D - MHV Dtaseline）/MHV DBaseli.,e x 100%, 〉21% indicated no fluid responsiveness, with a sensitivity of 100%, a specificity of 71.2%, and an area under the receiver operating characteristic curve of 0.918. Conclusions： during fluid expansion, hepatic venous S-wave velocity can be used to monitor CO, whether or not it is increasing. AMHV D 〉21% indicated a lack of fluid responsiveness, thus helping to decide when to stop infusions.

关键词： Fluid Challenge Hepatic Venous Flow Venous Return

δ-catenin表达水平对乳腺癌患者静息态脑功能的影响

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中国医学影像技术 2024年第5期40卷 724-729页

作者：薛明团杜伟曹家骏蒋玉涵宋段张俊毅苗延巍大连医科大学附属第一医院放射科辽宁大连116011 赤峰学院附属医院CT、MR科内蒙古赤峰024000 赤峰学院附属医院病理科内蒙古赤峰024000

目的观察δ-catenin表达水平对乳腺癌患者静息态脑功能的影响。方法前瞻性纳入104例女性乳腺癌患者,根据δ-catenin表达水平将其分为高表达组(DH组,n=51)及低表达组(DL组,n=53);另以36名女性健康志愿者为对照组。行神经心理学测试;采集... 详细信息

目的观察δ-catenin表达水平对乳腺癌患者静息态脑功能的影响。方法前瞻性纳入104例女性乳腺癌患者,根据δ-catenin表达水平将其分为高表达组(DH组,n=51)及低表达组(DL组,n=53);另以36名女性健康志愿者为对照组。行神经心理学测试;采集静息态功能MRI(rs-fMRI),记录组间脑功能参数存在差异脑区;以Spearman相关分析上述脑区脑功能参数[低频振幅(ALFF)、比率ALFF(fALFF)、局部一致性(ReHo)及功能连接强度(FCS)]与受试者一般资料及神经心理学测试评分结果的相关性。结果3组fALFF、ReHo及FCS值差异均有统计学意义[家族误差(FWE)校正,P均<0.05]。DH组及DL组左侧颞下回fALFF值均高于对照组(FWE校正,P均<0.05);DH组右侧颞下回及DL组右侧颞中回、右侧颞下回、右侧梭状回ReHo值均低于对照组(FWE校正,P均<0.05);DH组左侧豆状核、左侧壳核、左侧梭状回、左侧距状裂周围皮层及左侧颞下回FCS值均高于DL组(FWE校正,P均<0.05),DH组左侧豆状核、左侧壳核、左侧梭状回、左侧距状裂周围皮层FCS值均高于对照组(FWE校正,P均<0.05),DL组左侧舌回、左侧豆状核及左侧壳核FCS值均高于对照组(FWE校正,P均<0.05)。DH组与DL组存在差异脑区FCS值与CogPCA结果呈低度正相关(r=0.313,P<0.05)。DH组与对照组存在差异脑区的fALFF值与连线测试A(TMT A)及连线测试B(TMT B)结果均呈低度正相关(r=0.301、0.310,P均<0.05),ReHo值与TMT B结果呈低度负相关(r=-0.307,P<0.05),FCS值与TMT A、TMT B呈弱/低度正相关(r=0.282、0.309,P均<0.05)、与数字符号替代测试(DSST)呈低度负相关(r=-0.363,P<0.05)。DL组与对照组存在差异脑区的fALFF值与简易精神状态检查(MMSE)、蒙特利尔认知评估(MoCA)、中文听觉词汇学习测验(AVLT)短时记忆及DSST呈弱/低度负相关(r=-0.399、-0.362、-0.344、-0.288,P均<0.05)。结论δ-catenin表达水平对乳腺癌患者脑功能有一定影响,可致双侧大脑半球脑网络非对称性改变,并通过影响左侧颞下回、左侧豆状核、左侧壳核及左侧梭状回致记忆力下降。

关键词：乳腺癌磁共振成像

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长期荷载作用下钢-混凝土组合梁设计方法

沈阳建筑大学学报（自然科学版） 2024年第2期40卷 276-283页

作者：王庆贺戴蕊宏王仕奇杜威尤广迪沈阳建筑大学土木工程学院辽宁沈阳110168 浙江大学建筑工程学院浙江杭州310058 中建铁路投资建设集团有限公司北京100855

目的分析翼板混凝土时效变形对钢-混凝土组合梁长期性能的影响,提出相应的设计方法,供工程应用参考。方法结合已有的试验数据,对现行规范中组合梁长期性能设计方法进行适用性评估;在此基础上,充分考虑混凝土收缩、徐变、开裂及组合梁... 详细信息

目的分析翼板混凝土时效变形对钢-混凝土组合梁长期性能的影响,提出相应的设计方法,供工程应用参考。方法结合已有的试验数据,对现行规范中组合梁长期性能设计方法进行适用性评估;在此基础上,充分考虑混凝土收缩、徐变、开裂及组合梁界面滑移等多方面因素的综合影响,提出并验证单跨与两跨钢-混凝土组合梁长期性能的计算方法。结果提出的组合梁长期性能设计方法可有效预测单跨组合梁的长期跨中挠度和两跨组合梁的长期中支座负弯矩及跨中挠度,采用随龄期调整的有效模量法得到的长期跨中挠度预测值与试验值比为0.976,预测值与试验值最大相差16.5%,而采用规范建议值得到的组合梁预测值与试验值比为0.782。结论多跨连续组合梁长期性能受到负弯矩作用范围的影响显著,提出的计算方法适用于单跨和两跨钢-混凝土组合梁长期性能预测,该方法能够显著提升预测精度。

关键词：组合梁收缩徐变跨中挠度设计方法

Personalized aspheric intraocular lens implantation based on corneal spherical aberration: a review

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International Journal of Ophthalmology(English edition) 2019年第11期12卷 1788-1792页

作者： wei du wei Lou Qiang Wu Department of Ophthalmology Shang hai Jiao Tong University Affiliated Sixth People’s Hospital

With the evolution of cataract surgery from visual rehabilitation to refractive surgery, aspheric intraocular lenses(IOLs) are being increasingly used in the field of ophthalmology. This increased use can be attributed to negative or zero spherical aberrations with unique optical designs, which counteract some of the positive spherical aberrations of the cornea. These alterations reduce the total spherical aberration of human eyes and improve the visual acuity in patients with cataract postoperatively. At present, various types of aspheric IOLs are used worldwide. Although the implantation of aspheric IOL is beneficial to the patients who need correction of spherical aberrations, much controversy is still associated with ocular residual spherical aberrations that facilitate the best visual quality for patients postoperatively. In order to provide reference for future clinical work and scientific research, this report reviews the relationship between the ocular residual spherical aberration of human eyes and visual quality.

关键词： corneal spherical aberration aspheric intraocular lens visual quality

基于形态学性状的洪平杏与近缘种种间关系研究

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植物科学学报 2024年第1期42卷 14-22页

作者：刘志娥屈定镰谭霄华胡丹杜巍汪小凡武汉大学生命科学学院武汉430072 神农架林区林业管理局湖北神农架442499 太原市第三十七中学太原030012

本研究通过野外调查获得洪平杏(Armeniaca hongpingensis ***&***)、杏(*** Lam.)、梅(*** Siebold)和杏梅(*** *** Makino)有关的叶、花、果、果核及枝条的21个定量性状和15个定性性状,并对这些数据进行了聚类分析。结果显示,无论是PA... 详细信息

本研究通过野外调查获得洪平杏(Armeniaca hongpingensis ***&***)、杏(*** Lam.)、梅(*** Siebold)和杏梅(*** *** Makino)有关的叶、花、果、果核及枝条的21个定量性状和15个定性性状,并对这些数据进行了聚类分析。结果显示,无论是PAM聚类还是UPGMA聚类分析都可清晰地将4种杏属植物分开,说明物种之间具有明显的区分特征。主成分分析的前3个主成分中,一年生枝颜色、被毛情况,叶及果实被毛,叶形指标(叶形、叶尖、叶基)和果核表面特征的绝对权重值都在0.9以上,表明这些性状在4种杏属植物的分类中具有重要的作用。电镜扫描观察结果发现,供试花粉均是单粒花粉,等极,辐射对称,具3孔萌发沟。杏、梅、杏梅的花粉表面纹饰均为条纹状,但洪平杏的表面纹饰为间断条纹,且有不明显穿孔。4种植物叶上表皮细胞均具条纹状角质增厚。与其他种相比,洪平杏细胞表面条纹常弯曲、交叠,无固定走向。根据聚类分析结果和微形态特征,支持将洪平杏作为区别于梅和杏的一个独立种的处理。

关键词：洪平杏种间关系微形态孢粉学

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空间氢氧燃料电池技术发展现状与趋势分析

电源技术 2024年第3期48卷 445-453页

作者：周子阳杜玮王星显罗若尹邓呈维上海空间电源研究所上海200245

针对空间应用场景下的能源需求,对空间氢氧燃料电池技术现状和发展趋势进行分析,总结国内外在空间氢氧燃料电池发电技术的发展趋势,面向利用液氢液氧推进剂的一次燃料电池以及月面可再生电池应用场景,对多种空间电源技术方案进行对比,... 详细信息

针对空间应用场景下的能源需求,对空间氢氧燃料电池技术现状和发展趋势进行分析,总结国内外在空间氢氧燃料电池发电技术的发展趋势,面向利用液氢液氧推进剂的一次燃料电池以及月面可再生电池应用场景,对多种空间电源技术方案进行对比,发现空间氢氧燃料电池在运载火箭上面级推进剂利用、月面探测能源系统、月球原位资源利用、长时间月面驻留等应用场景具有较高潜力。通过分析空间应用场景下氢氧燃料电池电源系统特点,对未来空间氢氧燃料电池技术发展趋势,空间氢氧燃料电池技术发展方向提出展望。

关键词：空间场景氢氧燃料电池电源系统月面资源利用

Rebuilding motor function of the spinal cord based on functional electrical stimulation

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Neural Regeneration Research 2016年第8期11卷 1327-1332页

作者： Xiao-yan Shen wei du wei Huang Yi Chen Electronic Information School Nantong University Co-innovation Center of Neuroregeneration Nantong University Medical School Nantong University

Rebuilding the damaged motor function caused by spinal cord injury is one of the most serious challenges in clinical *** function of the neural pathway under the damaged sites can be rebuilt using functional electrical stimulation *** this study,the locations of motor function sites in the lumbosacral spinal cord were determined with functional electrical stimulation technology.A three-dimensional map of the lumbosacral spinal cord comprising the relationship between the motor function sites and the corresponding muscle was *** on the individual experimental parameters and normalized coordinates of the motor function sites,the motor function sites that control a certain muscle were *** pulse sequences were delivered to the determined motor function sites in the spinal cord and hip extension,hip flexion,ankle plantarflexion,and ankle dorsiflexion movements were successfully *** results show that the map of the spinal cord motor function sites was *** map can provide guidance for the selection of electrical stimulation sites during the rebuilding of motor function after spinal cord injury.

关键词： nerve regeneration spinal cord injury functional electrical stimulation rebuilding motor function movement control spinal cord lumbosacral spinal cord motor function sites hip extension movement hip flexion movement ankle plantarflexion ankle dorsiflexion neural regeneration