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Effect of ultraviolet mutagenesis on heterotrophic strain mutation and bioleaching of low grade copper ore

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Journal of Central South University 2017年第10期24卷 2245-2252页

作者： WU ai-xiang HU Kai-jian WANG Hong-jiang zhang ai-qing YANG Ying School of Civil and Environmental Engineering University of Science and Technology Beijing School of Resources and Environmental Engineering Jiangxi University of Science and Technology

The effect of ultraviolet mutagenesis on a heterotrophic strain(Providencia JAT-1) mutation was studied and bioleaching of low grade copper ore with mutant bacteria was investigated. The results show that the activity of bacteria was improved after ultraviolet mutagenesis; the best irradiation time was 120 s. Compared to the original bacteria, the cells density of mutant bacteria at stationary phase increased by 26% and ammonia produced by mutant bacteria increased by 12%. Higher activity of bacteria leads to a higher copper extraction rate. The bioleaching performance of Providencia JAT-1 was improved after UV mutagenesis. The copper extraction rate with mutant bacteria increased by 10.6% compared to the original bacteria. The ore surface was corroded and the fine particles were absent after bioleaching. Free copper oxide and copper silicates could be leached out easily by using JAT-1; a small part of the copper sulfide can also be leached out. Bioleaching using JAT-1 is more effective than ammonia leaching and copper extraction rate with mutant bacteria was 21.1% higher than that by ammonia leaching under the same condition.

关键词： ultraviolet mutagenesis bioleaching heterotrophic strain ammonia low grade copper ore

Synthesis,spectroscopic and electrochemical property of an unsymmetrical porphyrin and its Zn compound

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Chinese Chemical Letters 2010年第7期21卷 769-773页

作者： Chang Fu Zhuang Yu Jing zhang ai qing Xia Wen Hui Lian Yun Fang Wang Ping zhang Tong Shun Shi College of Chemistry Jilin UniversityChangchun 130023China

In this article,a new 5-（p-maleicaminophenyl）-10,15,20-triphenylporphyrin（H_2P） and relative zinc compound（ZnP） were synthesized and characterized by means of elemental analyses,UV-vis,IR,MS and 1H NMR ***,we have investigated the fluorescence spectroscopy of these *** oxidation and reduction properties of the compounds were studied by the cyclic voltarnmetry,the oxidation-reduction potentials were obtained.

关键词： Synthesis Porphyrin Cyclic voltammetry Fluorescence

Correlation of An Ultrasonic Scoring System and Intraoperative Blood Loss in Placenta Accreta Spectrum Disorders: A Retrospective Cohort Study

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Biomedical and Environmental Sciences 2021年第2期34卷 163-169页

作者： CHEN Lian SHI Hui Feng JIANG Hai SHI Xiao Ming WANG Yuan Yuan zhang ai qing CHONG Yi Wen ZHAO Yang Yu Department of Obstetrics and Gynecology Peking University Third HospitalBeijing 100191China

Objective This study aims to investigate the correlation of an ultrasonic scoring system with intraoperative blood loss(IBL) in placenta accreta spectrum(PAS) *** A retrospective cohort study was conducted between January 2015 and November *** data for patients with PAS have been obtained from medical records. Generalized additive models were used to explore the nonlinear relationships between ultrasonic scores and IBL. Logistic regressions were used to determine the differences in the risk of IBL ≥ 1,500 m L among groups with different ultrasonic *** A total of 332 patients participated in the analysis. Generalized additive models showed a significant positive correlation between score and blood loss. The amount of IBL was increased due to the rise in the ultrasonic score. All cases were divided into three groups according to the scores(low score group: ≤ 6 points, n = 147;median score group: 7-9 points, n = 126;and high score group: ≥ 10 points, n = 59). Compared with the low score group, the high score group showed a higher risk of IBL≥ 1,500 m L [odds ratio, 15.09;95% confidence interval(3.85, 59.19);P ≤ 0.001] after a multivariable *** The risk of blood loss equal to or greater than 1,500 m L increases further when ultrasonic score greater than or equal to 10 points, the preparation for transfusion and referral mechanism should be considered.

关键词： Ultrasonic scoring system Intraoperative blood loss Placenta accreta spectrum disorders

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有向图并行计算中一种新的结点调度算法

计算机学报 2009年第11期32卷 2178-2186页

作者：张爱清莫则尧北京应用物理与计算数学研究所高性能计算中心北京100094

在基于有向图的并行计算中,给定图剖分后,如何设计结点调度方案使得并行执行时间最短,是典型的NP完全问题.针对此问题,文中提出一种新的基于顺逆交替迭代技术的启发式调度算法,并给出该算法的并行实现.严格的理论推导证明,新算法在一定... 详细信息

在基于有向图的并行计算中,给定图剖分后,如何设计结点调度方案使得并行执行时间最短,是典型的NP完全问题.针对此问题,文中提出一种新的基于顺逆交替迭代技术的启发式调度算法,并给出该算法的并行实现.严格的理论推导证明,新算法在一定的假设条件下,从任何初始调度方案出发,均可以单调收敛.在数百个处理器上的并行数值实验表明,与常用的调度算法相比,新算法可在付出很少的开销代价下显著提高整体并行效率.

关键词：有向图并行计算结点调度算法顺逆交替迭代技术

“population explosion”的隐喻概念

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上海翻译 1999年第2期 29-32页

作者：张爱卿河南大学外语部

自从新马尔萨斯主义者把ｅｘｐｌｏｓｉｏｎ与ｐｏｐｕｌａ－ｔｉｏｎ结合起来，用于描绘本世纪５０－６０年代席卷全球的第三次人口浪潮以来，汉语里就不断出现“人口爆炸”外来字眼。接踵而来的又有“消费爆炸”，“欲望爆炸”，“知... 详细信息

自从新马尔萨斯主义者把ｅｘｐｌｏｓｉｏｎ与ｐｏｐｕｌａ－ｔｉｏｎ结合起来，用于描绘本世纪５０－６０年代席卷全球的第三次人口浪潮以来，汉语里就不断出现“人口爆炸”外来字眼。接踵而来的又有“消费爆炸”，“欲望爆炸”，“知识爆炸”等词语。将英语ｅｘｐｌｏｓ...

关键词： explosion population metaphorical concept E/C translation

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带理性运动极限的序列二次规划算法

北京工业大学学报 2008年第11期34卷 1121-1126页

作者：隋允康张爱清龙连春北京工业大学机械工程与应用电子技术学院北京100022

序列二次规划(SQP)算法的基本思想是通过一系列的二次规划(QP)子问题来逐次逼近原问题.为了给定QP子问题一个更加合适的求解空间(超多面体),将理性运动极限应用于SQP算法,提出了一种带理性运动极限的序列二次规划算法,从而以较为理性的... 详细信息

序列二次规划(SQP)算法的基本思想是通过一系列的二次规划(QP)子问题来逐次逼近原问题.为了给定QP子问题一个更加合适的求解空间(超多面体),将理性运动极限应用于SQP算法,提出了一种带理性运动极限的序列二次规划算法,从而以较为理性的方式求解搜索方向,而且也有利于确定搜索步长,数值算例表明这一方法是可行且有效的。

关键词：非线性约束优化 SQP算法 Hesse阵理性运动极限

Effect of pyrite content on chalcopyrite flotation under different regrinding conditions

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International Journal of Minerals,Metallurgy and Materials 2025年第1期32卷 49-57页

作者： Zejun Wang qing Shi Guofan zhang Yuxuan Zhu Binbin Li School of Minerals Processing and Bioengineering Central South UniversityChangsha 410083China Key Laboratory of Hunan Province for Clean and Efficient Utilization of Strategic Calcium-containing Mineral Resources Central South UniversityChangsha 410083China

This study aimed to investigate the effect of varying pyrite(Py)content on copper(Cu)in the presence of different regrinding conditions,which were altered using different types of grinding media:iron,ceramic balls,and their mixture,followed by flotation in the cleaner *** flotation performance of rough Cu concentrate can be improved by changing the regrinding conditions based on the Py *** electron microscopy,X-ray spectrometry,ethylenediaminetetraacetic acid disodium salt extraction,and X-ray photoelectron spectroscopy studies illustrated that when the Py content was high,the use of iron media in regrinding promoted the generation of hydrophilic Fe OOH on the surface of Py and improved the Cu *** ceramic medium with a low Py content prevented excessive Fe OOH from covering the surface of chalcopyrite(Cpy).Electrochemical studies further showed that the galvanic corrosion current of Cpy-Py increased with the addition of Py and became stronger with the participation of iron media.

关键词： chalcopyrite regrinding media pyrite galvanic corrosion flotation

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谷胱甘肽-富勒烯光敏剂的合成及光动力学

精细化工 2019年第4期36卷 582-587页

作者：张孝焱马艺函张爱清中南民族大学化学与材料科学学院湖北武汉430074

以还原性谷胱甘肽(GSH)为主要原料,通过亲核加成反应键合至C_(60)上,合成了一种水溶性富勒烯光敏剂(C_(60)-OH-GSH),并采用UV-Vis、FTIR和DLS对其结构组成进行表征。结果表明:C_(60)-OH-GSH在水溶液中形成了平均粒径约126 nm的纳米颗粒... 详细信息

以还原性谷胱甘肽(GSH)为主要原料,通过亲核加成反应键合至C_(60)上,合成了一种水溶性富勒烯光敏剂(C_(60)-OH-GSH),并采用UV-Vis、FTIR和DLS对其结构组成进行表征。结果表明:C_(60)-OH-GSH在水溶液中形成了平均粒径约126 nm的纳米颗粒,并且能够稳定存在于多种生理溶液中,具有优异的生物相容性。光动力治疗结果显示,在1μmol/L的浓度下,C_(60)-OH-GSH就能被强度为20 mW/cm^2自然光激发诱导产生大量的活性氧,使4种肿瘤细胞(U87-MG、A549、Hep G2和DU145)活性分别下降至60%～90%;同时,在避光条件下,50μmol/L的C_(60)-OH-GSH对正常细胞没有损伤。

关键词：富勒烯还原性谷胱甘肽光敏剂光动力治疗功能材料

Visual electrophysiological assessment of children with poor response to treatment for functional amblyopia

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International Journal of Ophthalmology(English edition) 2025年第2期18卷 315-322页

作者： Dong-qing Yuan Wei-Wei zhang Liu-Wei Gu qing-Huai Liu Department of Ophthalmology Jiangsu Province Hospitalthe First Affiliated Hospital of Nanjing Medical UniversityJiangsu Women and Children Health HospitalNanjing 210029Jiangsu ProvinceChina

aiM:To assess the visual electrophysiological outcomes in children with functional amblyopia who exhibited poor response to conventional ***:Twenty-one children with functional amblyopia,aged 5.7±2.1y(range:4-10y),underwent comprehensive ophthalmic and refractive *** domain-optical coherence tomography(SD-OCT)and multifocal electroretinography(mfERG)were conducted to analyze the macular retinal thickness and the first-order response P1 ring of the mfERG in the amblyopic eye(AE)compared to the fellow good eye(GE).RESULTS:Initially,visual acuity in the AE ranged from 20/800 to 20/40,while the GE exhibited a range of 20/25 to 20/20(Paid in identifying potential hidden retinal defects and predicting the prognosis of the amblyopic eye.

关键词： functional amblyopia poor response optical coherence tomography multifocal electroretinography retinal defects