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Sorl1 knockout inhibits expression of brain-derived neurotrophic factor:involvement in the development of late-onset Alzheimer's disease 被引量:2
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作者 Mingri Zhao xun chen +7 位作者 Jiangfeng Liu Yanjin Feng chen Wang Ting Xu Wanxi Liu Xionghao Liu Mujun Liu Deren Hou 《Neural Regeneration Research》 SCIE CAS CSCD 2024年第7期1602-1607,共6页
Sortilin-related receptor 1(SORL1)is a critical gene associated with late-onset Alzheimer’s disease.SORL1 contributes to the development and progression of this neurodegenerative condition by affecting the transport ... Sortilin-related receptor 1(SORL1)is a critical gene associated with late-onset Alzheimer’s disease.SORL1 contributes to the development and progression of this neurodegenerative condition by affecting the transport and metabolism of intracellularβ-amyloid precursor protein.To better understand the underlying mechanisms of SORL1 in the pathogenesis of late-onset Alzheimer s disease,in this study,we established a mouse model of SorI1 gene knockout using cluste red regularly inters paced short palindro mic repeats-associated protein 9 technology.We found that Sorl1-knocko ut mice displayed deficits in learning and memory.Furthermore,the expression of brain-derived neurotrophic factor was significantly downregulated in the hippocampus and co rtex,and amyloidβ-protein deposits were observed in the brains of 5orl1-knockout mice.In vitro,hippocampal neuronal cell synapses from homozygous Sorl1-knockout mice were impaired.The expression of synaptic proteins,including Drebrin and NR2B,was significantly reduced,and also their colocalization.Additionally,by knocking out the Sorl1 gene in N2a cells,we found that expression of the N-methyl-D-aspartate receptor,NR2B,and cyclic adenosine monophosphate-response element binding protein was also inhibited.These findings suggest that SORL1 participates in the pathogenesis of late-onset Alzheimer s disease by regulating the N-methyl-D-aspartate receptor NR2B/cyclic adenosine monophosphate-response element binding protein signaling axis. 展开更多
关键词 brain-derived neurotrophic factor late-onset Alzheimer’s disease N-methyl-D-aspartate receptor sortilin-related receptor 1 SYNAPSE
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Cu/CeO_(2)上可见光辅助热催化合成NH_(3):H_(2)O存在下NO通过CO还原的途径
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作者 宋昕杰 范世鹏 +4 位作者 蔡泽华 杨洲 陈旬 付贤智 戴文新 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 2023年第6期168-179,共12页
NH_(3)不仅是关键的工业化学原料,而且是未来可再生能源的无碳燃料和可运输的载体.目前,工业合成NH_(3)仍然以传统的Haber-Bosch反应为主,需要300-500°C的高温和20-30 MPa的压力.为克服这些缺点,研究者设计了NO-CO-H_(2)O反应体系... NH_(3)不仅是关键的工业化学原料,而且是未来可再生能源的无碳燃料和可运输的载体.目前,工业合成NH_(3)仍然以传统的Haber-Bosch反应为主,需要300-500°C的高温和20-30 MPa的压力.为克服这些缺点,研究者设计了NO-CO-H_(2)O反应体系.在该反应中,通过有毒气体CO在H_(2)O存在的条件下将NO还原成NH_(3),这是一种近乎理想的生产NH_(3)的方法.目前,已经报道了Pt/Al2O_(3)在NO-CO-H_(2)O反应中具有较高的NH_(3)选择性,但反应温度(400°C)仍然较高,不利于实际应用.因此,在低温条件下引入光照,通过光辅助热催化NO-CO-H_(2)O反应来获得NH_(3)产品,是一种极具发展潜力的方法.研究人员通过密度泛函理论(DFT)研究发现,Cu在NO还原反应中具有很高的活性和NH_(3)选择性,且Cu在水煤气(CO+H_(2)O)变换反应中具有较高的活性.CeO_(2)具有丰富氧空位同时能充当碳酸盐的储存位点,还可以起到稳定分散铜的作用.因此,本文将具有局域表面等离子体共振(LSPR)效应的金属Cu负载在具有氧空位的棒状CeO_(2)上形成Cu/CeO_(2)纳米复合材料,并研究了其催化NO-CO-H_(2)O反应性能.结果表明,Cu/CeO_(2)不仅在100-270°C下表现出较好的CO和NO去除效率,且可以选择性地催化还原NO为NH_(3).其中,5%Cu/CeO_(2)表现出最优催化活性,210°C时NO转化率为94.4%和NH_(3)选择性为66.5%.在相同温度下,可见光可以进一步提高NO转化率(97.7%)和NH_(3)选择性(69.1%).通过对NO-CO-H_(2)O反应进行分步活性测试,发现该反应的主要过程由水煤气变化反应生成活性H^(*)及其进一步与NO发生选择性催化还原反应两部分组成.准原位电子顺磁共振、原位漫反射傅立叶变换红外光谱和密度泛函理论计算表明,在Cu/CeO_(2)上NO-CO-H_(2)O的反应机理是CO首先与H_(2)O反应形成HCO_(3)^(*)中间物,然后分解成CO_(2)和活性H^(*),最后NO与活性H^(*)反应产生NH_(3).而可见光诱导Cu的LSPR效应能有效地将催化剂的光吸收范围拓宽至可见光,同时其产生的热电子能有效提高催化剂表面电子密度,从而促进了HCO_(3)^(*)分解为CO_(2)和活性H^(*);另外,在CeO_(2)上再生了氧空位(H_(2)O的活化点),进而增加了NH_(3)产量.综上,本文提供了一种在温和条件下合成NH_(3)的可行性方法,能为合成NH_(3)工艺提供一种新途径. 展开更多
关键词 NO-CO-H_(2)O反应 NH_(3)合成 局域表面等离子体共振 氧空位 Cu/CeO_(2)
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Experimental Study on Entropy Features in Machining Vibrations of A Thin-Walled Tubular Workpiece
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作者 Kaibo Lu Xin Wang +2 位作者 xun chen Xinyu Pang Fengshou Gu 《Journal of Dynamics, Monitoring and Diagnostics》 2023年第1期61-68,共8页
In machining processes,chatter vibrations are always regarded as one of the major limitations for production quality and efficiency.Accurate and timely monitoring of chatter is helpful to maintain stable machining ope... In machining processes,chatter vibrations are always regarded as one of the major limitations for production quality and efficiency.Accurate and timely monitoring of chatter is helpful to maintain stable machining operations.At present,most chatter monitoring methods are based on the energy level at specified chatter frequencies or frequency bands.However,the spectral features of chatter could change during machining operations due to complexity and time-varying dynamics of the physical machining process.The purpose of this paper is to investigate the time-varying chatter features in turning of thin-walled tubular workpieces from the perspective of entropy.The airborne acoustics was selected as the source of information for machining condition monitoring.First,corresponding to the distinguishing surface topographies relevant to machining conditions,the features of the sound signal emitted during turning of the thin-walled cylindrical workpieces were extracted using the spectral analysis and wavelet packet transform,respectively.It was shown that the dominant vibration frequency as well as the energy distribution could shift with the transition of the machining status.After that,two relative entropy indicators based on the spectrum and the wavelet packet energy were constructed to identify chattering events in turning of the thin-walled tubes.The experimental results demonstrate that the proposed indicators could accurately reflect the transition of machining conditions with high sensitivity and robustness in comparison with the traditional FFT-based methods.The achievement of this study lays the foundations of the online chatter monitoring and control technique for turning of the thin-walled tubular workpieces. 展开更多
关键词 MACHINING chatter relative entropy thin-walled work pieces
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氧空位修饰的暴露TiO_(2){001}的Ru/TiO_(2)增强光热协同CO_(2)甲烷化活性和稳定性 被引量:2
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作者 王可 何仕辉 +3 位作者 林云志 陈旬 戴文新 付贤智 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 2022年第2期391-402,共12页
利用太阳能在温和条件下实现CO_(2)还原反应,不仅可以缓解过度消耗化石能源造成的能源危机,还可以改善诸如温室效应和海洋酸化等环境问题.光热协同催化可以有效降低催化反应温度,具有较大的应用前景.本文利用Ru与暴露TiO_(2){001}晶面的... 利用太阳能在温和条件下实现CO_(2)还原反应,不仅可以缓解过度消耗化石能源造成的能源危机,还可以改善诸如温室效应和海洋酸化等环境问题.光热协同催化可以有效降低催化反应温度,具有较大的应用前景.本文利用Ru与暴露TiO_(2){001}晶面的TiO_(2)载体产生的金属-载体相互作用,经过高温氢气煅烧后,获得具有丰富表面氧空位的Ru/TiO_(2)催化剂.活性测试结果表明,具有丰富表面氧空位的Ru/TiO_(2)表现出优异的CO_(2)甲烷化活性,反应过程中甲烷的TOF值在300°C时可以达到22 h-1,但该催化剂却表现出较差的稳定性,在反应10小时后,甲烷的TOF值逐渐降低到19 h-1.将紫外光引入到Ru/TiO_(2)热催化甲烷化体系中,甲烷的TOF值增加到30 h-1,且兼具高稳定性.热催化反应过程中逐渐消失的表面氧空位和部分氧化的Ru是活性降低的主要原因.在光热协同反应中,光生电子的产生稳定了Ru表面的电子密度,同时也再生了催化剂上表面氧空位,这有效地提高了反应的活性和稳定性.程序升温原位红外和X射线光电子能谱实验结果表明,当催化剂表面具有丰富的表面氧空位时,CO_(2)可以有效地在Ru纳米粒子上解离成CO中间体,随后吸附在Ru上的CO中间体解离成表面碳物种,并加氢产生甲烷.在热催化反应过程中,Ru纳米粒子逐渐被氧化成Ru Ox物种,且表面氧空位被CO中间物种覆盖,降低了催化反应的稳定性.当紫外光引入到上述反应中,催化剂的表面氧空位可有效提高光生载流子的分离能力.TiO_(2)载体产生的光电子转移至Ru表面,稳定了金属Ru纳米粒子的价态.另外,载体产生的光生空穴加速了H_(2)质子化,提高了催化剂对氢气的活化迁移能力,促进了CO中间体的加氢甲烷化反应,进而再生表面氧空位.因此在紫外光照下,兼顾提高了热催化CO_(2)甲烷化的活性和稳定性.值得注意的是,当Ru负载于暴露少量TiO_(2){001}晶面的TiO_(2)载体上时,产生了强金属-载体相互作用并抑制了H_(2)在催化剂上的吸附活化,不利于产生表面氧空位.因此暴露少量TiO_(2){001}晶面的Ru/TiO_(2)催化剂也不利于光生载流的产生和分离,这导致热催化或光热协同催化反应活性较低. 展开更多
关键词 光热协同催化CO_(2)还原 氧空位 Ru/TiO_(2) 金属-载体相互作用
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通过调节反应物气体吸附电子转移行为实现热驱动ZnO光催化CO还原和H_(2)氧化反应 被引量:1
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作者 王中明 王洪 +4 位作者 王笑笑 陈旬 于岩 戴文新 付贤智 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 2021年第9期1538-1552,共15页
传统热催化和低温光催化体系在实际应用中都存在技术缺陷.近些年,人们通过将光和热耦合,克服它们各自的局限性,开创了光热协同催化新领域.目前已在CO减排、CO甲烷化和VOCs降解等诸多应用领域得到应用.当然,随着光热催化的发展,研究者也... 传统热催化和低温光催化体系在实际应用中都存在技术缺陷.近些年,人们通过将光和热耦合,克服它们各自的局限性,开创了光热协同催化新领域.目前已在CO减排、CO甲烷化和VOCs降解等诸多应用领域得到应用.当然,随着光热催化的发展,研究者也一直在思考光热协同的内在作用机理.目前大多数的机理分析都是从材料本身出发,通过研究表面反应、光吸收或金属与载体之间的电子转移行为来探讨光热协同效应.然而,表面反应只是多相光催化反应的其中一个步骤,此外还包括反应物的扩散和吸附及产物的脱附和扩散,其中反应物的吸附过程因其多变的吸附行为可能在整个反应过程中起着重要的作用.光热协同可能通过作用于气体吸附过程来调节反应的选择性和活性,但到目前为止,两者之间的内在联系尚不清楚.所以,从反应物气体吸附行为(尤其是吸附电子转移行为)的角度深入研究光热协同效应具有重要意义.本文在光催化CO还原和H_(2)氧化体系中引入一定的热条件,希望通过热驱动效应影响H_(2)/CO吸附时的电子转移行为,进而改变反应行为.为简化实验附加条件,选用常见的具有合适带隙宽度以及良好光吸收的ZnO作为研究材料,通过水热法合成了在(100)晶面具有氧空位(V_(Os))的ZnO样品,引入气敏传感系统检测不同光热条件下的H_(2)/CO气体吸附电子转移行为,并结合多种原位手段从物质结构和气体吸附两个角度出发,分析光热条件下气体吸附行为变化的机理.与我们预测一致,在紫外光照下随着温度的升高,光热协同作用于(002)晶面,原位生长了锌空位(V_(Zn)s),为H_(2)分子提供吸附位点.H_(2)从Vos位点吸附转移到V_(Zn)s上,并导致H_(2)(ads)从得电子转变为失电子行为(形成有利于H_(2)氧化的定向吸附),从而发生H_(2)氧化反应.对于同样吸附在高表面能(002)晶面上的CO分子来说,光热协同效应通过抬升材料费米能级来改变其电子转移行为,CO(ads)由失电子转变为得电子行为(形成有利于CO还原的定向吸附),并进一步被失去电子的H_(2)(ads)还原.此外,还发现CO或H_(2)的光催化氧化反应的发生只依赖于CO或H_(2)单分子的定向活化(不考虑O2的吸附和活化),表明其归属于E-R反应过程.而CO的光催化还原反应需要同时满足CO和H_(2)双分子的定向活化,可能归属于L-H反应过程.综上,本文研究结果表明,光热协同内在作用可能是通过改变ZnO材料结构,调节反应物吸附动力学中的电子转移行为,从而引起反应物的定向活化,进而改变反应选择性. 展开更多
关键词 光热协同 电子转移行为 吸附动力学控制 原位表征 费米能级
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晚期肝细胞癌一线系统治疗药物有效性和安全性的网络荟萃分析 被引量:4
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作者 罗林华 寻琛 秦叔逵 《临床肿瘤学杂志》 CAS 2021年第9期799-807,共9页
目的比较晚期肝细胞癌一线系统治疗药物的有效性和安全性,供临床实践作参考。方法网络检索PubMed、Cochrane Library、Embase和Web of Science等文献数据库,检索时限均为建库至2021年6月,根据预设的纳入标准筛选文献进行网络荟萃分析。... 目的比较晚期肝细胞癌一线系统治疗药物的有效性和安全性,供临床实践作参考。方法网络检索PubMed、Cochrane Library、Embase和Web of Science等文献数据库,检索时限均为建库至2021年6月,根据预设的纳入标准筛选文献进行网络荟萃分析。结果共纳入12项随机对照研究,合计8058例患者。网络荟萃分析结果显示,相较于索拉非尼,信迪利单抗联合贝伐珠单抗生物类似物(IBI305)、阿替利珠单抗联合贝伐珠单抗和多纳非尼均降低了患者的死亡风险(HR=0.57,95%CI:0.43~0.75;HR=0.58,95%CI:0.42~0.80;HR=0.83,95%CI:0.70~0.99),该3种治疗方式有最高的P-score值,分别为0.956、0.948和0.764;在有或无“大血管侵犯/肝外转移”的两组患者亚组中,3种治疗方案的排名类似;安全性方面,除安慰剂之外,多纳非尼因不良事件终止研究治疗、减量研究药物和暂停研究治疗的P-score值均位居首位。结论晚期肝细胞癌一线系统治疗药物中,信迪利单抗联合贝伐珠单抗生物类似物、阿替利珠单抗联合贝伐珠单抗和多纳非尼单药治疗均可显著改善晚期肝细胞癌患者的总生存时间;而多纳非尼的安全性和耐受性更佳。 展开更多
关键词 晚期肝细胞癌 系统治疗 一线治疗 随机对照试验 有效性 安全性 网络荟萃分析
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基于二叉树模型的农业可转债定价研究——以天康转债为例 被引量:3
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作者 方欣 丁胜 +1 位作者 荀晨 郭登倩 《中国林业经济》 2021年第1期95-97,105,共4页
以天康转债为例,通过构建二叉树模型对其进行定价研究,可以得到2020年4月3日天康转债的理论价格为180.69元,当日实际价格为176.88元,两者相差不大。为了更加直观地显示运用二叉树模型计算出的理论价格与实际价格的偏差,形成30个交易日... 以天康转债为例,通过构建二叉树模型对其进行定价研究,可以得到2020年4月3日天康转债的理论价格为180.69元,当日实际价格为176.88元,两者相差不大。为了更加直观地显示运用二叉树模型计算出的理论价格与实际价格的偏差,形成30个交易日的理论价格与实际价格对比图,研究表明二叉树法得出的理论价格与实际价格基本一致。将二叉树定价模型运用到其他农业可转债中,除宏辉转债外,其他可转债理论价格与实际价格偏差不大。 展开更多
关键词 可转债定价 二叉树 农业可转债
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螺旋藻肽聚糖复合物胶囊对比肝复乐胶囊一线治疗晚期肝细胞癌的前瞻性、随机、双盲对照、全国多中心的Ⅱ期临床研究报告
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作者 寻琛 秦叔逵 +7 位作者 程颖 顾康生 吴穷 白玉贤 章龙珍 徐建明 石建华 潘垚天 《临床肿瘤学杂志》 CAS 北大核心 2020年第11期961-968,共8页
目的探索新药螺旋藻肽聚糖复合物胶囊(K-001)在晚期肝细胞癌(HCC)患者中的安全性和有效性。方法本研究为前瞻性、随机、双盲、阳性对照、全国多中心的Ⅱ期临床研究。自2012年9月至2016年3月,共入组100例晚期HCC患者,随机分为K-001组(试... 目的探索新药螺旋藻肽聚糖复合物胶囊(K-001)在晚期肝细胞癌(HCC)患者中的安全性和有效性。方法本研究为前瞻性、随机、双盲、阳性对照、全国多中心的Ⅱ期临床研究。自2012年9月至2016年3月,共入组100例晚期HCC患者,随机分为K-001组(试验组)和肝复乐胶囊组(对照组)。采用RECIST 1.1版标准评价客观疗效;NCI CTC 4.0版标准评价不良事件。结果治疗后,试验组和对照组的中位疾病进展时间(TTP)分别为1.48个月和1.41个月(P=0.946),中位总生存时间(OS)分别为5.17个月和4.57个月(P=0.374),差异均无统计学意义。无高危因素亚组分析显示,K-001有延长生存的趋势(7.0个月vs.4.67个月,P=0.447;9.10个月vs.4.67个月,P=0.675)。K-001治疗后血红蛋白、白蛋白、淋巴细胞和嗜酸性粒细胞较对照组显著升高,且以上指标与死亡风险呈负相关;碱性磷酸酶和血小板/淋巴细胞比值(PLR)较对照组显著降低,且与死亡风险呈正相关。“无门脉侵犯”亚组中,K-001组治疗后疼痛轻于对照组(P=0.002)。K-001安全性良好,无与药物肯定或可能相关的严重不良事件发生。结论K-001治疗国人晚期HCC的疗效与肝复乐胶囊相似,分层分析显示,在部分亚组有生存获益的趋势和减轻癌痛的作用;同时,安全性良好,值得在特定人群扩大样本量进一步临床探索。 展开更多
关键词 肝细胞癌(HCC) 螺旋藻肽聚糖复合物胶囊(K-001) 治疗 临床研究/Ⅱ期
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Research progress in enhanced bioleaching of copper sulfides under the intervention of microbial communities 被引量:8
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作者 Sheng-hua Yin Lei-ming Wang +2 位作者 Ai-xiang Wu xun chen Rong-fu Yan 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2019年第11期1337-1350,共14页
Compared with the traditional pyrometallurgical process, copper bioleaching has distinctive advantages of high efficiency and lower cost, enabling efficiently extracts of valuable metal resources from copper sulfides.... Compared with the traditional pyrometallurgical process, copper bioleaching has distinctive advantages of high efficiency and lower cost, enabling efficiently extracts of valuable metal resources from copper sulfides. Moreover, during long-term industrial applications of bioleaching, many regulatory enhancements and technological methods are used to accelerate the interfacial reactions. With advances in microbial genetic and sequencing technologies, bacterial communities and their mechanisms in bioleaching systems have been revealed gradually. The bacterial proliferation and dissolution of sulfide ores by a bacterial community depends on the pH, temperature, oxygen, reaction product regulation, additives, and passivation substances, among other factors. The internal relationship among the influencing factors and the succession of microorganism diversity are discussed and reviewed in this paper. This paper is intended to provide a good reference for studies related to enhanced bioleaching. 展开更多
关键词 BIOLEACHING copper SULFIDE HEAP LEACHING microbial community SUCCESSION ENHANCED mechanism
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格拉司琼透皮贴片预防抗肿瘤治疗所致恶心呕吐的前瞻性、多中心的真实世界研究报告
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作者 寻琛 秦叔逵 +24 位作者 马军 李进 周承志 黄慧强 马树东 王湛 秦茵茵 刘加军 王潇潇 臧远胜 秦海峰 肖健 王蔷 魏哲威 范志平 魏小娟 宣丽 曾铭玥 张国庆 许昕 高岩 王涛 焦晓栋 袁芃 乔滨 《临床肿瘤学杂志》 CAS 2021年第5期385-390,共6页
目的探讨采用真实世界研究模式,在中国癌症患者中评价格拉司琼透皮贴片(granisetron transdermal delivery system,GTDS)预防抗肿瘤治疗所致恶心呕吐(antitumor drugs-induced nausea and vomiting,DINV)的效果、安全性和治疗价值。方... 目的探讨采用真实世界研究模式,在中国癌症患者中评价格拉司琼透皮贴片(granisetron transdermal delivery system,GTDS)预防抗肿瘤治疗所致恶心呕吐(antitumor drugs-induced nausea and vomiting,DINV)的效果、安全性和治疗价值。方法本研究是一项前瞻性、多中心、非干预性观察研究,自2019年4月至2020年4月期间共入选了48家医院1572例预防性使用GTDS止吐的成年癌症患者。所有患者的止吐治疗方案由其主管医师酌情决定。研究中收集患者的基线资料、抗肿瘤治疗方案及药物剂量、止吐治疗方案和不良事件等数据。结果从治疗开始至末剂治疗结束后24小时期间(PEEP期)有62.5%(983/1572)的患者获得了恶心呕吐的完全缓解(CR),59.4%(934/1572)的患者达到恶心呕吐的完全控制(CC)。此外,从治疗开始至末剂治疗期间逐日CR率从67.0%上升到93.1%,呈现逐步递增趋势。接受高致吐化疗(HEC)和中致吐化疗(MEC)方案患者的CR率分别为52.1%和61.0%。多因素Logistic回归分析结果表明,<50岁、女性、ECOG PS评分≥1和中/高度致吐化疗为影响PEEP期CR的危险因素。研究过程中,有19.8%的患者出现了轻微的便秘、头痛等症状,但未报告严重不良事件。结论真实临床实践中,GTDS可以有效地预防抗肿瘤治疗所致恶心和呕吐的发生,其安全性良好,依从性高,有利于实现DINV的全程管理。 展开更多
关键词 格拉司琼透皮贴片 抗肿瘤治疗所致恶心呕吐 真实世界研究 全程管理
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Accelerating leaching of copper ore with surfactant and the analysis of reaction kinetics 被引量:10
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作者 Chun-ming Ai Ping-ping Sun +2 位作者 Ai-xiang Wu xun chen Chao Liu 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2019年第3期274-281,共8页
To solve the problem of low permeability and lower extraction rates of high-mud ores, a surfactant was added as a penetrant to the pregnant leaching solution during column leaching tests. On the basis of the theories ... To solve the problem of low permeability and lower extraction rates of high-mud ores, a surfactant was added as a penetrant to the pregnant leaching solution during column leaching tests. On the basis of the theories of physical chemistry and seepage flow mechanics, the mechanism by which seepage is enhanced under the effects of the surfactant was analyzed. The results show that the action modes of the surfactant were divided into four aspects: changing the wettability of the ore, reducing the viscosity of the leaching solution, adsorbing onto the surface of ore, and enhancing the permeability effect. The findings of column leaching tests demonstrated that permeability was substantially improved by the surfactant. In the later period of leaching, the permeability coefficient was two times higher than that of the control group. Meanwhile, the ore extraction rate increased by approximately 10%. During the leaching process, the surface tension of the solution did not substantially change, and that of the solution with surfactant increased slightly. The kinetics analysis of ore column leaching illustrated that the leaching processes were controlled by both internal diffusion(principal factor) and chemical reaction. 展开更多
关键词 SURFACTANT PERMEABILITY REACTION KINETICS LEACHING
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Implantable collamer lens for residual refractive error after corneal refractive surgery 被引量:6
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作者 xun chen Xiao-Ying Wang +2 位作者 Xi Zhang Zhi chen Xing-Tao Zhou 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2016年第10期1421-1426,共6页
AIM:To assess the safety,efficacy,predictability and stability of implantable collamer lens(ICL) for residual refractive error after corneal refractive surgery.METHODS: This study evaluated 19 eyes of 12 patients ... AIM:To assess the safety,efficacy,predictability and stability of implantable collamer lens(ICL) for residual refractive error after corneal refractive surgery.METHODS: This study evaluated 19 eyes of 12 patients who underwent ICL implantation after corneal refractive surgeries.They were followed up for 1y to 5y of uncorrected distance visual acuity(UDVA),corrected distance visual acuity(CDVA),manifest refractive error,flat and steep K value,axial length,intraocular pressure,corneal endothelial cell density,adverse events after ICL surgery.RESULTS: The mean follow-up period was 39.05 ±19.22 mo(range,1-5y).Spherical equivalent refractive error changed from-7.45±3.02 D preoperatively to-0.85±1.10 D 1wk to 1mo after ICL implantation,with the safety and efficacy indices being 1.12 and 1.15,respectively.A total of 52.63% of eyes were within ±0.5 D of the predicted spherical equivalents,73.68% were within ±1.0 D.A trend of mild regression towards myopia with axial elongation after 5y was observed.One eye with mild anterior capsule opacity and retinal detachment 1y after surgery were observed.CONCLUSION: ICL implantation is safe and effective for the correction of residual refractive error after corneal refractive surgeries,especially in moderate to high residual myopia. 展开更多
关键词 implantable collamer lens radial keratotomy photorefractive keratectomy laser-assisted in situ keratomileusis laser-assisted subepithelial keratomileusis
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免疫检查点抑制剂相关性肺炎的临床特点及分型研究 被引量:6
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作者 王锋 秦叔逵 +11 位作者 华海清 刘秀峰 赵颖 施毅 王琴 成远 曹梦苒 程颖 李慧 陈歆妮 寻琛 郝利平 《临床肿瘤学杂志》 CAS 2021年第6期541-549,共9页
目的观察免疫检查点抑制剂相关性肺炎(CIP)患者的临床特点。方法回顾性分析本中心CIP患者的详细资料,根据影像学特点、临床表现和治疗转归进行临床分型。结果自2016年9月1日至2020年8月31日,共564例患者在我院肿瘤内科接受PD-1/PD-L1抑... 目的观察免疫检查点抑制剂相关性肺炎(CIP)患者的临床特点。方法回顾性分析本中心CIP患者的详细资料,根据影像学特点、临床表现和治疗转归进行临床分型。结果自2016年9月1日至2020年8月31日,共564例患者在我院肿瘤内科接受PD-1/PD-L1抑制剂治疗,其中PD-1/PD-L1抑制剂单药134例,PD-1/PD-L1抑制剂联合化疗、分子靶向药物、VEGF抑制剂或CTLA-4抑制剂430例。共发生19例CIP,ICIs用药至发生CIP的中位时间为71天(2~444天),其中1级CIP 1例,2级CIP 4例,3-4级CIP 14例,CIP发生率为3.4%(19/564)。1例1级CIP患者自愈,其余18例患者均接受糖皮质激素治疗,8例治愈,7例好转,3例无效并死于CIP,死亡率15.8%(3/19)。根据患者的影像学资料、临床表现和治疗转归的特点,可将CIP分为磨玻璃型、斑片型和网格型3种类型,磨玻璃型对激素治疗敏感,预后较好;斑片型对激素治疗中度敏感,预后欠佳;网格型对激素治疗敏感性不佳,预后最差。结论CIP是一类少见但有潜在致命危险的免疫相关不良反应(irAEs),临床分型有助于CIP的早期诊断、预测疗效和判断预后。 展开更多
关键词 免疫检查点抑制剂 免疫相关不良反应 肺炎 糖皮质激素
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Geleophysic dysplasia caused by a mutation in FBN1:A case report 被引量:3
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作者 Ying Tao Qing Wei +1 位作者 xun chen Guang-Min Nong 《World Journal of Clinical Cases》 SCIE 2021年第24期7175-7180,共6页
BACKGROUND Geleophysic dysplasia(GD)presents the characterized clinical manifestations of acromelic dysplasia,including extremely short stature,short limbs,small hands and feet,stubby fingers and toes,joint stiffness ... BACKGROUND Geleophysic dysplasia(GD)presents the characterized clinical manifestations of acromelic dysplasia,including extremely short stature,short limbs,small hands and feet,stubby fingers and toes,joint stiffness and others.It is clinically distinct from the other acromelic dysplasia in terms of symptoms such as cardiac valvular abnormalities,progressive hepatomegaly and tracheal stenosis.CASE SUMMARY We report on a Chinese 9-year-old girl with GD with the c.5243G>T(p.C1748F)mutation in FBN1(fibrillin 1,OMIM 134797).She was born in Guangxi Zhuang Autonomous Region of China.The patient presented with typical clinical features of GD and recurrent respiratory tract infections over 6 years.Laboratory studies and chest computed tomography(CT)scan indicated bronchopneumonia.Her echocardiography revealed mild mitral valve thickening with regurgitation.Laryngopharyngeal CT and electronic bronchoscopy revealed severe glottic stenosis.Echocardiography examination displayed mild mitral valve thickening and regurgitation.Ophthalmic examination did not reveal myopia or lens dislocation.Treated with ceftriaxone sodium and methylprednisolone sodium succinate for injection as well as methylprednisolone orally,patient’s symptoms had improved.CONCLUSION GD is a rare genetic condition that can cause life-threatening cardiovascular and respiratory problems.This study also found that the identified genotype of GD could be related to different clinical phenotypes. 展开更多
关键词 Fibrillin 1 Geleophysic dysplasia Acromelic dysplasia Short stature Tracheal stenosis Case report
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Agglomeration and leaching behaviors of copper oxides with different chemical binders 被引量:2
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作者 Sheng-hua Yin Lei-ming Wang +1 位作者 xun chen Ai-xiang Wu 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2021年第7期1127-1134,共8页
The chemical binder is one of the critical factors affecting ore agglomeration behavior and leaching efficiency.In this study,we in-vestigated the effect of the type of binder and mass fraction of the H_(2)SO_(4)solut... The chemical binder is one of the critical factors affecting ore agglomeration behavior and leaching efficiency.In this study,we in-vestigated the effect of the type of binder and mass fraction of the H_(2)SO_(4)solution used on the curing,soaking,and leaching behavior of ag-glomerations.The results revealed that Portland cement(3CaO·SiO_(2),2CaO·SiO_(2),and 3CaO·Al_(2)O_(3))was the optimal binder for obtaining a well-shaped,stable agglomeration structure.A higher extraction rate was achieved when using Portland cement than that obtained using sodi-um silicate,gypsum,or acid-proof cement.An excessive geometric mean size is not conducive to obtaining well-shaped agglomerations and desirable porosity.Using computed tomography(CT)and MATLAB,the porosity of two-dimensional CT images in sample concentrations L1-L3 was observed to increase at least 4.5vol%after acid leaching.Ore agglomerations began to be heavily destroyed and even to disinteg-rate when the sulfuric acid solution concentration was higher than 30 g/L,which was caused by the excessive accumulation of reaction products and residuals. 展开更多
关键词 AGGLOMERATION BINDER acid leaching copper oxide sulfuric acid solution
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Erratum:A Search for Solar Axions and Anomalous Neutrino Magnetic Moment with the Complete PandaX-Ⅱ Data[CHIN.PHYS.LETT.38(2021)011301] 被引量:3
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作者 周小朋 曾鑫宁 +63 位作者 宁旭阳 阿布都沙拉木·阿布都克力木 陈葳 谌勋 陈云华 程晨 崔祥仪 樊英杰 方德清 符长波 付孟婷 耿立升 Karl Giboni 顾琳慧 郭绪元 韩柯 何昶达 黄迪 黄焱 黄彦霖 黄周 季向东 巨永林 李帅杰 刘华萱 刘江来 芦晓盈 马文博 马余刚 冒亚军 孟月 倪恺翔 宁金华 任祥祥 商长松 申国防 司琳 谈安迪 王安庆 王宏伟 王萌 王秋红 王思广 王为 王秀丽 王舟 武蒙蒙 吴世勇 邬维浩 夏经铠 肖梦姣 谢鹏伟 燕斌斌 杨继军 杨勇 喻纯旭 袁鞠敏 袁影 张丹 张涛 赵力 郑其斌 周济芳 周宁 《Chinese Physics Letters》 SCIE CAS CSCD 2021年第10期71-72,共2页
In our published letter,[1]we have identified a minor error in Figs.2 and 3.Instead,we have 2111 events in these two plots with 646,249,382,and 834 events in Run 9(20.0 ton·day),Run 10(19.4 ton·day),Run 11–... In our published letter,[1]we have identified a minor error in Figs.2 and 3.Instead,we have 2111 events in these two plots with 646,249,382,and 834 events in Run 9(20.0 ton·day),Run 10(19.4 ton·day),Run 11–1(24.2 ton·day),and Run 11–2(37.1 ton·day).The mistake is due to an incorrect application of a small energy non-linearity(known as the BLS non-linearity)in making plots,but has no impact to the final results.Figures 2 and 3 are now updated in this note. 展开更多
关键词 LETTER error
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Molecular dynamics simulation of the material removal in the scratching of 4H-SiC and 6H-SiC substrates 被引量:4
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作者 Zige Tian xun chen Xipeng Xu 《International Journal of Extreme Manufacturing》 EI 2020年第4期86-100,共15页
Single crystal silicon carbide(SiC)is widely used for optoelectronics applications.Due to the anisotropic characteristics of single crystal materials,the C face and Si face of single crystal SiC have different physica... Single crystal silicon carbide(SiC)is widely used for optoelectronics applications.Due to the anisotropic characteristics of single crystal materials,the C face and Si face of single crystal SiC have different physical properties,which may fit for particular application purposes.This paper presents an investigation of the material removal and associated subsurface defects in a set of scratching tests on the C face and Si face of 4H-SiC and 6H-SiC materials using molecular dynamics simulations.The investigation reveals that the sample material deformation consists of plastic,amorphous transformations and dislocation slips that may be prone to brittle split.The results showed that the material removal at the C face is more effective with less amorphous deformation than that at the Si face.Such a phenomenon in scratching relates to the dislocations on the basal plane(0001)of the SiC crystal.Subsurface defects were reduced by applying scratching cut depths equal to integer multiples of a half molecular lattice thickness,which formed a foundation for selecting machining control parameters for the best surface quality. 展开更多
关键词 material removal mechanism molecular dynamics simulation subsurface defects SCRATCHING 4H-SiC and 6H-SiC
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Enhanced copper recovery from low grade copper sulfide ores through bioleaching using residues produced by fermentation of agricultural wastes 被引量:1
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作者 Wei chen Shenghua Yin +2 位作者 Qing Song Leiming Wang xun chen 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2022年第12期2136-2143,共8页
Effects of residues produced by agricultural wastes fermentation(AWF)on low grade copper sulfide ores bioleaching,copper recovery,and microbial community were investigated.The results indicated that adding appropriate... Effects of residues produced by agricultural wastes fermentation(AWF)on low grade copper sulfide ores bioleaching,copper recovery,and microbial community were investigated.The results indicated that adding appropriate bulk of AWF made contributions to low grade copper sulfide ores bioleaching,which may be mainly realized through reducing the passivation layer formed by Fe3+hydrolysis.Improved copper recovery(78.35%)and bacteria concentration(9.56×10^(7)cells·mL^(−1))were yielded in the presence of 5 g·L^(−1)AWF.The result of 16S rDNA analysis demonstrated that microbial community was differentiated by adding AWF.Bacteria proportion,such as Acidithiobacillus ferrooxidans,Moraxella osloensis,and Lactobacillus acetotolerans changed distinctly.Great difference between samples was showed according to beta diversity index,and the maximum value reached 0.375.Acidithiobacillus ferrooxidans accounted for the highest proportion throughout the bioleaching process,and that of sample in the presence of 5 g·L^(−) AWF reached 28.63%.The results should show reference to application of agricultural wastes and low grade copper sulfide ores. 展开更多
关键词 low grade copper sulfide ores BIOLEACHING agricultural wastes FERMENTATION microbial community
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Ecological Compensation: A Key to Sustainable Development in the Guizhou Province Karst Region, Southwest China 被引量:2
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作者 Chuanyan Zhou Brita M. Svensson +2 位作者 Junhua Yan xun chen Kun Li 《Open Journal of Forestry》 2014年第3期212-222,共11页
The conflict between poverty and the resulting over-exploitation of natural resources on the one hand, and ecological restoration and sustainable development on the other hand, in the southwest China karst region was ... The conflict between poverty and the resulting over-exploitation of natural resources on the one hand, and ecological restoration and sustainable development on the other hand, in the southwest China karst region was studied. In this region, the karst forest (a mixed evergreen and deciduous broad-leaved forest) is rapidly degrading due to over-exploitation (sloping farming). We suggest that an Ecological Compensation (EC) model should be established with: financial institutions, local people, and a third part as an intermediate link. The process would continue for 20 years. As a case study we used Bangui town (3800 families) in the upper reaches of Pearl River. The per capita income of residents was used as the benchmark. The compensation would start with 80%, and decrease to 20% over a period of 20 years. Infrastructure investment would decrease from 20% of the total person’s compensation to 5% as the farmers increasingly use alternative income sources. The EC includes compensation for individual, infrastructure, and environmental investments. The total EC for Bangui would be 305,064 × 104 yuan during the 20 years. 展开更多
关键词 Bangui Town Ecosystem Service KARST Forest Net Primary Production OPPORTUNITY Cost Rocky DESERTIFICATION Sloping FARMING
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Multi-Modal Reasoning Medical Diagnosis System Integrated With Probabilistic Reasoning 被引量:1
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作者 Jia Tian xun chen Sheng-Ping Dong 《International Journal of Automation and computing》 EI 2005年第2期134-143,共10页
In this paper, a Multi Modal Reasoning (MMR) method integrated with probabilistic reasoning is proposed for the diagnosis support module of the open eHealth platform. MMR is based on both Rule Based Reasoning (RBR) an... In this paper, a Multi Modal Reasoning (MMR) method integrated with probabilistic reasoning is proposed for the diagnosis support module of the open eHealth platform. MMR is based on both Rule Based Reasoning (RBR) and Case Based Reasoning (CBR). It is not only applied to the identification of diseases and syndromes based on medical guidelines, but also deals with exceptional cases and individual therapies in order to improve diagnostic accuracy. Moreover, a new rule expression frame is introduced to deal with uncertainty, which can represent and process vague, imprecise, and incomplete information. Furthermore, this system is capable of updating the attributes of rules and inducing rules with a small data sample. Keywords Information management - uncertainty - decision making Jia Tian received her BSc degree from China University of Mining and Technology (CUMT), Beijing, China in 2002. She is currently pursuing her PhD at the University of Nottingham, United Kingdom. Her research interests include expert system, artificial intelligence and data mining, especially Medical Decision Support System, Case Based Reasoning, Rule Based Reasoning and Bayesian Networks.Xun Chen obtained his B. Eng. from Fuzhou University. He received his M. Sc. from Zhejiang University and his Ph. D from Liverpool John Moores University. He has been a visiting professor to Fuzhou University since 2001. He specialises in advanced manufacturing technology including application of computer science, mechatronics and artificial intelligence to broad engineering application. He has published more than 100 research papers. Dr Chen is a founder member of the International Committee of Abrasive Technology. Before his employment at Nottingham, Dr Chen was a lecturer of Mechanical Engineering at the University of Dundee. Prior to that, he was a research fellow, a Royal Society Royal Fellow at Liverpool John Moores University and a lecturer at Fuzhou University.Sheng-Ping Dong graduated from China University of Traditional Chinese Medicine, Beijing, China. She is an attending doctor of Traditional Chinese Medicine with many years clinical experience in Exhibition Road Hospital, Beijing, China. 展开更多
关键词 Information management UNCERTAINTY decision making
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