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Initial experience of laparoendoscopic single-site radical prostatectomy with a novel purpose-built robotic system
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作者 Zheng Wang Chao Zhang +13 位作者 Chengwu Xiao Yang Wang Yu Fang Baohua Zhu Shouyan Tang xiaofeng wu Hong Xu Yi Zhou Lingfen wu Zhenjie wu Bo Yang Yi He Yi Liu Linhui Wang 《Asian Journal of Urology》 CSCD 2023年第4期467-474,共8页
Objective This prospective single-arm clinical trial aimed to evaluated the feasibility and safety of the application of the SHURUI system(Beijing Surgerii Technology Co.,Ltd.,Beijing,China),a novel purpose-built robo... Objective This prospective single-arm clinical trial aimed to evaluated the feasibility and safety of the application of the SHURUI system(Beijing Surgerii Technology Co.,Ltd.,Beijing,China),a novel purpose-built robotic system,in single-port robotic radical prostatectomy.Methods Sixteen patients diagnosed with prostate cancer were prospectively enrolled in and underwent robotic radical prostatectomy from October 2021 to August 2022 by the SHURUI single-port robotic surgical system.The demographic and baseline data,surgical,oncological,and functional outcomes as well as follow-up data were recorded.Results The mean operative time was 226.3(standard deviation[SD]52.0)min,and the mean console time was 183.4(SD 48.3)min,with the mean estimated blood loss of 116.3(SD 90.0)mL.The mean length of postoperative hospital stay was 4.50(SD 0.97)days.Two patients had postoperative complications(Clavien-Dindo Grade II),and both patients improved after conservative treatment.All patients’postoperative prostate-specific antigen levels decreased to below 0.2 ng/mL 1 month after discharge.The mean prostate-specific antigen level further decreased to a mean of 0.0219(SD 0.0641)ng/mL 6 months after surgery.Thirty days postoperatively,12 out of 16 patients reported using no more than one urinary pad per day,and all patients reported satisfactory urinary control without the need for pads 6 months after surgery.Conclusion The SHURUI system is safe and feasible in performing radical prostatectomy via both transperitoneal and extraperitoneal approaches.Tumor control and urinary continence were satisfying for patients enrolled in.The next phase involves conducting a large-scale,multicenter randomized controlled trial to thoroughly assess the effectiveness and safety of the new technology in a broader population. 展开更多
关键词 Laparoendoscopic single-site surgery Robotic surgical procedure Prostatectomy Prostatic cancer
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水滑石衍生的复合氧化物催化氧化挥发性有机气体的研究进展(英文) 被引量:8
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作者 李双德 王东东 +1 位作者 武晓峰 陈运法 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 北大核心 2020年第4期550-560,共11页
挥发性有机化合物(VOCs)是大气颗粒污染物(PM2.5)和臭氧污染的主要前体物,来源于工业活动(如溶剂使用过程)、汽车尾气以及植物排放等,具有毒性,对人类和自然生命产生危害.催化氧化技术是在催化剂表面,在较低的操作温度(200-450℃)下,将V... 挥发性有机化合物(VOCs)是大气颗粒污染物(PM2.5)和臭氧污染的主要前体物,来源于工业活动(如溶剂使用过程)、汽车尾气以及植物排放等,具有毒性,对人类和自然生命产生危害.催化氧化技术是在催化剂表面,在较低的操作温度(200-450℃)下,将VOCs非均相催化氧化成CO2和H2O,是一种最为有效的分解VOCs的方法,具有副产物少,能耗低的优点.VOCs分解用催化剂主要分为贵金属和金属氧化物两大类.贵金属催化剂活性高,但价格昂贵.因此科研工作者一直在诸多方面调控过渡金属氧化物,例如制备方法、组分协同、结构缺陷等,期望获得高活性、低成本的催化剂.水滑石(LDHs)是一种层状双金属氢氧化物,由带正电荷的金属氢氧化物层板和层间阴离子组成,可以表示为[M1-x^2+Mx^3+(OH)2](An-)x/n·mH2O.鉴于LDHs特有的结构特点,层板元素可调、比例可调等,其在一定温度下煅烧可以得到过渡金属复合氧化物(MMO)材料.由于LDHs的拓扑焙烧转变得到的MMO材料显示出许多利于多相催化反应的优点,如大表面积和多孔性、高热稳定性、良好的金属氧化物分散性等.水滑石基催化材料用于VOCs催化分解也引起了科研工作者的持续关注和研究,文献大多选择苯、甲苯、乙酸乙酯等工业活动中常用的挥发性有机溶剂作为探针分子来评估催化剂的活性、稳定性等参数.本综述将LDHs衍生的VOCs降解催化剂分为4类,整理了其近10年的研究进展:(1)含过渡金属的LDHs焙烧转变成MMO催化剂:系统论述了层板元素组成、层板元素比例、焙烧温度、制备方法等条件对催化活性的影响规律,阐明了不同处理条件下催化剂的物理化学特性(比表面积、孔结构、表面元素价态、氧缺陷、还原性)与催化活性的关联;(2)贵金属/MMO催化剂:比较了贵金属种类、LDHs载体种类、负载方式等因素对催化活性的影响规律,总结了贵金属负载在LDHs载体的优势;(3)核壳型MMO催化剂:分析了在氧化铝球、MOF等载体上原位负载LDHs的方法构筑多级结构的MMO催化剂,利于促进VOCs分解活性;(4)整体型MMO催化剂:满足VOCs分解实际应用,提出铝片基底上原位生长-煅烧制备高活性位点暴露的整体式催化剂的优点.在催化活性基础上着重介绍了水蒸气对活性的影响以及VOCs分解催化机理.同时提出了3点仍需努力的方向:LDHs向MMO拓扑转变机制认识不足;LDHs衍生的催化剂的VOCs分解机制研究不深入;催化剂活性降低-再生研究不透彻. 展开更多
关键词 VOCs氧化 水滑石 复合金属氧化物 水汽 氧化机理
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Building a Neural Network Model to Analyze Teachers’ Satisfaction with Online Teaching during the COVID-19 Ravages
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作者 Gangxin Wen Quanlong Guan +1 位作者 xiaofeng wu Weiqi Luo 《Journal of Computer and Communications》 2022年第1期91-114,共24页
The ravages of COVID-19 have forced schools in countries around the world to make a temporary shift from traditional, face-to-face teaching to online teaching. Are teachers in schools prepared to deal with this change... The ravages of COVID-19 have forced schools in countries around the world to make a temporary shift from traditional, face-to-face teaching to online teaching. Are teachers in schools prepared to deal with this change? We conducted a survey in which we distributed questionnaires to primary and secondary school teachers in Guangdong Province, China, asking them about their views on various aspects of online education. We received 498,481 questionnaires back, and over 80% of teachers were satisfied with the online resources, and over 68% of teachers were satisfied with the online platform and software. Immediately afterward, we analyzed the differences between urban and rural teachers on specific issues using cross-sectional analysis and chi-square tests and built a neural network model to achieve predictions of teacher satisfaction with an accuracy of nearly 90%. Finally, we analyzed the features that influence the decisions of the neural network. This epidemic has prompted the widespread use of online learning, and the insights we gain today will be helpful in the future. 展开更多
关键词 COVID-19 Online Education Neural Networks SATISFACTION
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利用Bi的SPR效应增强Bi_2WO_6的可见光催化NO氧化去除性能(英文) 被引量:7
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作者 张荔 杨超 +7 位作者 吕康乐 陆亚超 李覃 伍晓锋 李宇涵 黎小芳 范佳杰 李玫 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 北大核心 2019年第5期755-764,共10页
作为大气中的典型污染物之一,化石燃料燃烧产生的NO不仅会引起酸雨,还会影响人体呼吸系统.半导体光催化技术可以利用太阳能和空气中的氧气来分解环境污染物,因而得到了国内外学者的广泛关注.作为最具代表性的半导体光催化材料,TiO_2虽... 作为大气中的典型污染物之一,化石燃料燃烧产生的NO不仅会引起酸雨,还会影响人体呼吸系统.半导体光催化技术可以利用太阳能和空气中的氧气来分解环境污染物,因而得到了国内外学者的广泛关注.作为最具代表性的半导体光催化材料,TiO_2虽然具有较强的氧化能力和优异的生物相容性,但是其禁带宽度较大(3.2 eV)而只能被紫外光激发,无法充分利用太阳能.因此,开发新型可见光响应的半导体催化材料具有重要意义.Bi_2WO_6是一种独特的具有层状结构半导体光催化材料,因其具有可见光响应性能而受到了广泛关注;但是可见光响应范围窄(禁带宽度2.6?2.8 eV)以及其较快的光生载流子复合,导致Bi_2WO_6其光催化效率不高,迫切需要采取有效措施对Bi_2WO_6进行改性.贵金属(诸如金和银)纳米粒子可见光区的表面等离子体效应(SPR),可以用来增强半导体材料的可见光催化性能.但是,贵金属的价格昂贵,难以满足实际需求.近来的研究发现,非贵金属Bi同样具有类似的表面等离子体效应.因此,本文选用以乙二醇为还原剂,通过低温还原Bi(NO_3)_3的方式,在花球Bi_2WO_6表面,成功制备了沉积了Bi纳米球复合光催化次材料.本文用NO的可见光催化氧化来评价Bi/Bi_2WO_6复合材料的光催化性能的可见光催化性能,所使用的光源为可见光LED灯(λ>400 nm).结果发现:(1)单一组分的Bi金属和Bi_2WO_6前驱体花球均表现出非常差的光催化活性,NO去除率分别仅为7.7%和8.6%;(2)随着Bi纳米球的负载量从0增加至10 wt%,复合材料Bi/Bi_2WO_6的NO去除效率从12.3%稳定增加至53.1%至20 wt%时开始降低.这可能是由于Bi纳米球阻碍了Bi_2WO_6对光的吸收;(3)改性后的Bi/Bi_2WO_6具有良好的可见光催化稳定性,循环使用在五次后其活性变化不大.光催化机理研究结果显示,Bi/Bi_2WO_6增强的可见光NO去除性能归因于Bi纳米球的SPR效应.在可见光照射下,Bi纳米球的SPR效应产生的电场可以显著促进Bi_2WO_6的光生载流子分离效率.同时,Bi纳米球可以快速转移Bi_2WO_6导带上的光生电子,生成超氧游离基(·O_2~?),从而抑制了光生电子和空穴的复合.Bi_2WO_6表面的空穴可以被表面吸附水捕获,产生羟基自由基(·OH).在活性氧物种·OH和·O_2~?的不断进攻作用下,NO最终被氧化.本文为宽禁带半导体的非贵金属敏化,提升其可见光催化性能解决环境问题提供了新思路. 展开更多
关键词 Bi2WO6 表面等离子体 光催化 氧化氮
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光催化的氟效应 被引量:3
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作者 黎小芳 伍晓锋 +3 位作者 刘升卫 李宇涵 范佳杰 吕康乐 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 北大核心 2020年第10期1451-1467,共17页
半导体光催化因有望可持续地解决日益严峻的环境与能源问题而得到国内外学者的广泛关注.但是,以TiO2为代表的半导体光催化材料,存在光响应范围窄和光生载流子容易复合的问题,导致其光催化效率不高.为了提高半导体光催化效率,科学家们采... 半导体光催化因有望可持续地解决日益严峻的环境与能源问题而得到国内外学者的广泛关注.但是,以TiO2为代表的半导体光催化材料,存在光响应范围窄和光生载流子容易复合的问题,导致其光催化效率不高.为了提高半导体光催化效率,科学家们采取了许多策略对本征半导体光催化剂进行修饰改性,如表面敏化、贵金属沉积、元素掺杂和半导体复合等,以拓展光吸收范围和促进光生载流子分离.近来,高能面TiO2纳米晶的报道为高性能半导体光催化材料的设计提供了新的思路.在所有对TiO2进行修饰改性的元素里面,氟因其独特的性能而对TiO2光催化产生了深远影响:(1)(在酸性溶液里面)氟离子与TiO2强烈的配位作用(化学吸附)会改变TiO2光催化材料表面的化学结构,生成氟化钛(≡Ti-F),进而影响污染物在催化剂表面的吸附(反应式(1));≡Ti-OH+H++F-→≡Ti-F+H2O(1)(2)吸附在TiO2表面的氟离子,很难被空穴氧化成氟自由基(EθF·/F-=3.6 V vsNHE),只能将溶剂水氧化成羟基自由基(·OH).与本征TiO2空穴氧化产生的表面吸附态羟基自由基(·OHbounded)不同(反应式(2)),表面氟修饰后空穴氧化溶剂水产生的羟基自由基(反应式(3)),是可以脱离催化剂表面(在溶液中自由扩散的),也就是游离态羟基自由基(·OHfree).≡Ti-OH+h+→≡Ti····OH (·OHbounded)(2)≡Ti-F+H2O+h+→≡Ti-F+·OHfree+H+(3)本文主要从以下几个方面综述了氟效应对半导体光催化的影响:(1)TiO2光催化的表面氟效应,包括游离自由基效应、表面电子结构效应和电子清除剂效应;(2)TiO2光催化的氟掺杂效应,包括氟离子掺杂、氟离子与非金属离子共掺杂、以及氟离子与金属离子共掺杂;(3)TiO2的氟离子形貌控制效应,包括空心结构TiO2、高能面TiO2和介晶TiO2.此外,我们也将氟效应拓展到其它非TiO2半导体上,包括Bi2WO4, BiPO4, Fe2O3, SrTiO3和g-C3N4.本文还总结了氟效应在半导体光催化领域的应用,包括(1)化学品的光催化选择性氧化;(2)污染物的光催化选择性降解;(3)光催化分解水产氢;(4)光催化还原二氧化碳;(5)制备高热稳定性TiO2.最后总结了氟效应的优缺点,并对氟效应的前景进行了展望.现在仪器表征技术(特别是原位表征技术)的快速发展,为半导体光催化氟效应的深入研究提供了新的武器.将氟效应与其它方式的耦合,如表面等离子体效应、晶体缺陷和单原子催化,来进一步提高半导体光催化性能,是未来氟效应研究的发展方向. 展开更多
关键词 二氧化钛 光催化 掺杂 表面修饰
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离子交换法制备高光催化活性Bi_2WO_6@Bi_2S_3异质结纳米片(英文) 被引量:3
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作者 黄婷婷 李雨涵 +5 位作者 伍晓峰 吕康乐 李覃 李玫 杜冬云 叶恒朋 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 北大核心 2018年第4期718-727,共10页
社会经济快速发展的同时,也带来了日益严峻的环境污染问题.半导体光催化氧化技术因节能环保而在环境领域有广阔的应用前景.作为最具有代表性的半导体光催化材料,TiO_2因为其禁带宽度(3.2 eV)比较大,只能被紫外光激发,因而对太阳能的利... 社会经济快速发展的同时,也带来了日益严峻的环境污染问题.半导体光催化氧化技术因节能环保而在环境领域有广阔的应用前景.作为最具有代表性的半导体光催化材料,TiO_2因为其禁带宽度(3.2 eV)比较大,只能被紫外光激发,因而对太阳能的利用率较低.作为一种最简单的含铋层状氧化物,Bi_2WO_6的禁带宽度(2.7 eV)相对较小,可以部分利用太阳光中的可见光,因而受到广大研究者的青睐.但是,Bi_2WO_6光催化材料的可见光响应范围较窄,仅能被波长小于450 nm的光激发,且激发后的光生载流子容易复合,导致光催化效率不高.因此,迫切需要对Bi_2WO_6光催化材料进行结构修饰与改性,采用拓展其光响应范围和抑制载流子复合,来提高其光催化活性.本文采用离子交换法原位合成了具有核-壳结构的Bi_2S_3@Bi_2WO_6纳米片,充分利用Bi_2S_3优良的可见光响应性能和半导体异质结光催化剂的构建,来提高Bi_2WO_6的光催化活性.结果表明,随着Na2S·9H2O用量从0增加到1.5 g,所得催化剂的光活性不断提高,X3B的降解速率常数由0.40×10^(-3) min^(-1)增加到6.6×10^(-3) min^(-1),催化剂活性提高了16.5倍.当进一步增加Na2S·9H2O的用量时(1.5.3.0 g),复合催化剂的光活性下降.这是由于过多Na2S·9H2O的引入导致在催化剂表面生成了没有光活性的NaBiS2层(Bi_2S_3+Na_2S=2NaBiS_2),占据了催化剂的活性位点,阻碍了染料分子与催化剂的直接接触.Bi_2WO_6@Bi_2S_3异质结纳米片光活性的提高,可归因于Bi_2S_3的敏化作用极大拓展了复合催化剂的光响应范围;另一方面,Bi_2WO_6和Bi_2S_3两者之间的半导体异质结效应有效促进了光生载流子在空间的有效分离,抑制了光生电子-空穴的复合,从而提高了复合催化剂的催化效率. 展开更多
关键词 BI2S3 Bi2WO6 离子交换 光催化降解 纳米片
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Factors Research on the Influence of Leaching Rate of Nickel and Cobalt from Waste Superalloys with Sulfuric Acid 被引量:2
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作者 Xingxiang Fan Weidong Xing +5 位作者 Haigang Dong Jiachun Zhao Yuedong wu Bojie Li Weifeng Tong xiaofeng wu 《International Journal of Nonferrous Metallurgy》 2013年第2期63-67,共5页
Unlike the reported leaching technologies of waste superalloys, the process of the “atomized spray-sulfuric acid leaching nickel and cobalt” technology was put forward in the present work according to the compositio... Unlike the reported leaching technologies of waste superalloys, the process of the “atomized spray-sulfuric acid leaching nickel and cobalt” technology was put forward in the present work according to the compositions of waste superalloys. The effects of sulfuric acid temperature, concentration, leaching time, stirring speed and size of superalloys on leaching of Ni and Co from waste superalloys have been mainly investigated, and the optimum leaching conditions were determined and reported. The leaching rates for nickel and cobalt were 96.68% and 96.63%, respectively, and the contents of nickel and cobalt in leaching slag were 6.77% and 0.96%, respectively. The obtained leaching solution containing Ni and Co could be used for production of Ni and Co products after removal. 展开更多
关键词 WASTE SUPERALLOYS ACID LEACHING NICKEL COBALT LEACHING Rate
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Optimizing the electronic spin state and delocalized electron of NiCo_(2)(OH)_(x)/MXene composite by interface engineering and plasma boosting oxygen evolution reaction
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作者 Jingyao Xu Xia Zhong +2 位作者 xiaofeng wu Ying Wang Shouhua Feng 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2022年第8期129-140,I0004,共13页
The electrocatalytic activity of transition-metal-based compounds is closely related to the electronic configuration.However,optimizing the surface electron spin state of catalysts remains a challenge.Here,we develope... The electrocatalytic activity of transition-metal-based compounds is closely related to the electronic configuration.However,optimizing the surface electron spin state of catalysts remains a challenge.Here,we developed a spin-state and delocalized electron regulation method to optimize oxygen evolution reaction(OER)performance by in-situ growth of NiCo_(2)(OH)_(x) using Oswald ripening and coordinating etching process on MXene and plasma treatment.X-ray absorption spectroscopy,magnetic tests and electron paramagnetic resonance reveal that the coupling of NiCo_(2)(OH)_(x) and MXene can induce remarkable spin-state transition of Co^(3+)and transition metal ions electron delocalization,plasma treatment further optimizes the 3 d orbital structure and delocalized electron density.The unique Jahn-Teller phenomenon can be brought by the intermediate spin state(t2 _(g)^(5) e_(g)^(1))of Co^(3+),which benefits from the partial electron occupied egorbitals.This distinct electron configuration(t2_(g)^(5) e_(g)^(1))with unpaired electrons leads to orbital degeneracy,that the adsorption free energy of intermediate species and conductivity were further optimized.The optimized electrocatalyst exhibits excellent OER activity with an overpotential of 268 m V at 10 m A cm^(-2).DFT calculations show that plasma treatment can effectively regulate the d-band center of TMs to optimize the adsorption and improve the OER activity.This approach could guide the rational design and discovery of electrocatalysts with ideal electron configurations in the future. 展开更多
关键词 Transition metal compounds Electronic state control of surface/interface Electron spin state Delocalized electron Electrocatalytic material
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三维适形放疗联合高强度聚焦超声治疗前列腺癌临床疗效观察(英文)
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作者 Hui Yao Jinlan Gong +2 位作者 Li Li xiaofeng wu Jianjun Yu 《The Chinese-German Journal of Clinical Oncology》 CAS 2012年第3期164-167,共4页
Objective:Prostate cancer is a form of cancer that develops in the prostate,a gland in the male reproductive system.Prostate cancer tends to develop in men over the age of fifty;it is one of the most prevalent types o... Objective:Prostate cancer is a form of cancer that develops in the prostate,a gland in the male reproductive system.Prostate cancer tends to develop in men over the age of fifty;it is one of the most prevalent types of cancer in men.This article introduced a new method of prostate cancer treatment with the combination of three dimensional conformal radiation therapy (3D-CRT) and high-intensity focused ultrasound (HIFU),its efficacy was evaluated.Methods:From January 2004 to December 2009,95 patients were diagnosed with prostate cancer,among them,48 patients were received combined therapy with total irradiation of TD 60 Gy/30 Fx and 5 fractions of HIFU treatment,while 47 patients were received with pure 3D-CRT with total irradiation of TD (66-72) Gy/(33-36) Fx.Various indicators were evaluated,such as the local control rate and distant metastasis rate,the changes in blood PSA and fPSA,changes in T-lymphocyte subsets and NK cells,as well as acute adverse reaction of normal tissue.Results:The local response rate difference between the two groups had statistical significance (P < 0.05);the changes in blood PSA and fPSA were significant (P < 0.05);CD3+,CD4+,CD8+,CD4+/CD8+ and NK cells of the combined group increased obviously (P < 0.01),while the latter group had no increase (P > 0.05);the combined group had lower blood cells reduction and II-level acute adverse reaction of rectum,bladder and caput humeri than the pure group,but the II-level acute adverse reaction of urogenital canal in the combined group was higher (P < 0.05).Conclusion:The combined therapy with 3D-CRT and HIFU is a good way for the treatment of aged-related prostate cancer.It can ease the symptoms,control the disease and lengthen the survival time. 展开更多
关键词 高强度聚焦超声 前列腺癌 放射治疗 三维 T淋巴细胞亚群 应用 不良反应 生殖系统
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Mechanized Grafting Technology for Apple Seedlings
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作者 Zhiru LI xiaofeng wu +2 位作者 Lizhi HAN Quangang LI Beihang ZHANG 《Asian Agricultural Research》 2019年第2期100-101,105,共3页
The current cultivation of apple trees mainly relies on grafted seedlings to achieve seedling regeneration of apple trees. The commonly used splice grafting,V-shaped grafting and tongue grafting mostly use plastic fil... The current cultivation of apple trees mainly relies on grafted seedlings to achieve seedling regeneration of apple trees. The commonly used splice grafting,V-shaped grafting and tongue grafting mostly use plastic film for fixation and sealing. After one year,the wrapped plastic film needs to be removed to avoid affecting the growth of the seedlings. This paper introduces a brand new grafting technology which uses tongue grafting iron nails for fixation and growth fixation wax for sealing( SDRG). The process of mechanized grafting for apple nursery stock is determined,and the fixation and sealing problems with the grafting parts of seedlings are solved. The technology is characterized by quick speed,high efficiency,improved seedling survival rate lower labor cost and great significance to the promotion of industrialized nursery and mechanized grafting. 展开更多
关键词 GRAFTING FIXATION with IRON NAILS Process program Industrialized NURSERY
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亚临界或超临界反应的凝聚态化学
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作者 张媛 郑贝宁 +2 位作者 吴小峰 黄科科 冯守华 《化学进展》 SCIE CAS CSCD 北大核心 2023年第6期968-982,共15页
通过化学反应形成确定的和复杂的原子分子凝聚态,其原子分子间相互作用的多维度复合与协同,拓展了物质结构模式,体系性能发生突变,表现出凝聚态化学的某些特性。在特定条件下或在超临界条件下的歧化反应,产生锰金属离子以三种氧化态的... 通过化学反应形成确定的和复杂的原子分子凝聚态,其原子分子间相互作用的多维度复合与协同,拓展了物质结构模式,体系性能发生突变,表现出凝聚态化学的某些特性。在特定条件下或在超临界条件下的歧化反应,产生锰金属离子以三种氧化态的形式聚集成的复杂调制结构。本文从凝聚态化学角度出发,详细介绍了在亚/超临界水热条件下,原子尺度pn结固体的生成,量子IV特性与电场诱导超流现象,讨论了化学反应驱动的凝聚态转变问题。本文同时介绍了凝聚态流体的基本性质和各级凝聚尺度中气体分子参与的化学反应,包括化学键修复反应、水热反应、人工降雨和肿瘤的消退,以及超临界条件下凝聚态化学反应的机理和潜在应用。 展开更多
关键词 超临界 水热歧化反应 原子尺度pn结 玻色爱因斯坦凝聚 肿瘤消退
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Reinforcement learning based dynamic distributed routing scheme for mega LEO satellite networks 被引量:1
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作者 Yixin HUANG Shufan wu +5 位作者 Zeyu KANG Zhongcheng MU Hai HUANG xiaofeng wu Andrew Jack TANG Xuebin CHENG 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2023年第2期284-291,共8页
Recently,mega Low Earth Orbit(LEO)Satellite Network(LSN)systems have gained more and more attention due to low latency,broadband communications and global coverage for ground users.One of the primary challenges for LS... Recently,mega Low Earth Orbit(LEO)Satellite Network(LSN)systems have gained more and more attention due to low latency,broadband communications and global coverage for ground users.One of the primary challenges for LSN systems with inter-satellite links is the routing strategy calculation and maintenance,due to LSN constellation scale and dynamic network topology feature.In order to seek an efficient routing strategy,a Q-learning-based dynamic distributed Routing scheme for LSNs(QRLSN)is proposed in this paper.To achieve low end-toend delay and low network traffic overhead load in LSNs,QRLSN adopts a multi-objective optimization method to find the optimal next hop for forwarding data packets.Experimental results demonstrate that the proposed scheme can effectively discover the initial routing strategy and provide long-term Quality of Service(QoS)optimization during the routing maintenance process.In addition,comparison results demonstrate that QRLSN is superior to the virtual-topology-based shortest path routing algorithm. 展开更多
关键词 LEO satellite networks Mega constellation Multi-objective optimization Routing algorithm Reinforcement learning
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Inductive effect of Ti-doping in Fe_(2)O_(3)enhances the photoelectrochemical water oxidation
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作者 Yumei Lin Yan Wang +7 位作者 Hongxia Wang Jingjing Wang xiaofeng wu Jan P.Hofmann Giulio Gorni Victor A.de la Pena O'Shea Freddy E.Oropeza Kelvin H.L.Zhang 《Science China Chemistry》 SCIE EI CAS CSCD 2023年第7期2091-2097,共7页
Hematite(α-Fe_(2)O_(3))is an ideal oxide semiconductor candidate for photoelectrochemical(PEC)water splitting.Doping of Fe_(2)O_(3)is known to benefit the PEC water oxidation efficiency,but despite extensive research... Hematite(α-Fe_(2)O_(3))is an ideal oxide semiconductor candidate for photoelectrochemical(PEC)water splitting.Doping of Fe_(2)O_(3)is known to benefit the PEC water oxidation efficiency,but despite extensive research efforts,the underlying mechanism still remains elusive.In this work,we report a comprehensive study on the relationship between the electronic structure,interfacial reaction kinetics and PEC activity of Ti-doped Fe_(2)O_(3)photoanodes.The results show that the interfacial charge transfer efficiency at the Fe_(2)O_(3)/electrolyte interface is the main factor in the significant increase of the PEC activity of doped Fe_(2)O_(3).Electrochemical impedance spectroscopy reveals that the interfacial charge transfer efficiency is determined by energy overlap between the water oxidation potential and energy distribution of an intermediate surface state that has been identified as Fe^(IV)=O groups on Fe_(2)O_(3)surface generated during PEC process.Interestingly,the potential energy distribution of this intermediate surface state can be modulated by Ti doping,and a shift towards a more positive potential of the intermediate surface state increases the overlap with the water oxidation potential and thus enhances the kinetics of charge transfer for PEC water splitting.The origin of such potential energy modulation is traced to the inductive effect from Ti-doping on the Fe^(3+)/Fe^(4+)redox transition and the Fe-O bond covalency.Our results provide new insight into the mechanism for the doping effect on the PEC water splitting,introducing new strategies to optimize the PEC activity by tuning the redox properties of active metal oxides. 展开更多
关键词 HEMATITE surface states DOPING photoelectrochemical water splitting electronic structure
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Manipulation and observation of atomic-scale superlattices in perovskite manganate
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作者 Xiyang Wang Keke Huang +4 位作者 xiaofeng wu Long Yuan Liping Li Guangshe Li Shouhua Feng 《Chinese Chemical Letters》 SCIE CAS CSCD 2023年第12期481-485,共5页
Superlattices in crystals,particularly in perovskite oxides with strong correlation effects,can create new states of matter and produce peculiar physicochemical phenomena.However,the newfangled perovskite superlattice... Superlattices in crystals,particularly in perovskite oxides with strong correlation effects,can create new states of matter and produce peculiar physicochemical phenomena.However,the newfangled perovskite superlattices depend on physical deposition with unit-cell precision.It has been challenging to explore a new suitable chemical method to tailor perovskite superlattices.Herein,we present a new bottomup strategy to precisely prepare atomic-scale oxide superlattices of(LaMnO_(3))_(1)-(La_(1-x-y)Ca_(x)K_(y)MnO_(3))_(2)in a monodispersed perovskite La_(0.66)Ca_(0.29)K_(0.05)MnO_(3)(LCKMO).The special atomic-scale perovskite superlattices are demonstrated using SAED,HAADF-STEM,XRD,and atomic-resolution elemental mapping.Our experiments reveal that the perovskite superlattices can be fabricated under extreme hydrothermal conditions utilizing ultra-high concentrations of KOH.An approximate molten salt system in the hydrothermal process can induce the disproportionation reaction of MnO_(2)solids,which is vital to the growth of ordered perovskite superlattices.This work not only clarifies the hydrothermal growth process of perovskite oxides in extreme conditions,but also proposes a novel engineering route toward perovskite superlattices. 展开更多
关键词 Perovskite oxides Hydrothermal Ordered superstructure Perovskite superlattice Disproportionation reaction
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Learning curve and analysis of curative effects after balloon pulmonary angioplasty for chronic thromboembolic pulmonary hypertension
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作者 Cheng Hong Linna Hu +8 位作者 Haimin Liu xiaofeng wu Jianmin Lu Jiangpeng Lin Wenliang Guo Xishi Sun Jielong Lin Riken Chen Zhenzhen Zheng 《Chinese Medical Journal》 SCIE CAS CSCD 2023年第1期99-101,共3页
To the Editor:Chronic thromboembolic pulmonary hypertension(CTEPH)is a chronic progressive disease in which pulmonary artery pressure(PAP)increases and eventually leads to right heart failure and death.Balloon pulmona... To the Editor:Chronic thromboembolic pulmonary hypertension(CTEPH)is a chronic progressive disease in which pulmonary artery pressure(PAP)increases and eventually leads to right heart failure and death.Balloon pulmonary angioplasty(BPA)is a new and effective treatment for CTEPH patients who are unsuitable for surgery or who develop recurrent or persistent pulmonary hypertension after pulmonary endarterectomy(PEA).In recent years,major medical centers at home and abroad have been gradually developing and improving BPA,but overall,a unified treatment process and complication control strategy is lacking. 展开更多
关键词 HYPERTENSION BALLOON ANGIOPLASTY
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Fluorinated Covalent Organic Frameworks Coupled with Molecular Cobalt Cocatalysts for Efficient Photocatalytic CO_(2)Reduction
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作者 Zhiwei Fu Chang Shu +8 位作者 Xiaoyan Wang Linjiang Chen Xue Wang Lunjie Liu Kewei Wang Rob Clowes Samantha Y.Chong xiaofeng wu Andrew I.Cooper 《CCS Chemistry》 CSCD 2023年第10期2290-2300,共11页
The combination of covalent organic framework(COF)photosensitizers with molecular cocatalysts is a promising avenue for photocatalytic carbon dioxide(CO_(2))reduction.Here,a series of isostructural COFs was synthesize... The combination of covalent organic framework(COF)photosensitizers with molecular cocatalysts is a promising avenue for photocatalytic carbon dioxide(CO_(2))reduction.Here,a series of isostructural COFs was synthesized using linkers of different lengths,with or without partial fluorination.These COFs were investigated for photocatalytic CO_(2)reduction under visible-light irradiation when combined with cobalt(II)bipyridine complexes as a cocatalyst.Fluorination was found to enhance both CO_(2)affinity and catalytic activity,and a partially fluorinated COF,FBP-COF,achieved the highest CO_(2)-to-CO conversion efficiency,showing a carbon monoxide(CO)generation rate of 2.08 mmol h−1 g−1 and a 90%CO selectivity.FBP-COF also showed good stability under sacrificial conditions,generating CO for 50 h with a turnover number of 91.5.This activity is much higher than a homogeneous system using ruthenium bipyridine complexes as the photosensitizer combined with the same cobalt bipyridine complexes. 展开更多
关键词 carbon dioxide conversion PHOTOCATALYSIS covalent organic frameworks FLUORINATED solar energy conversion
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碳纳米管-膨胀石墨/环氧树脂复合材料的导热性能 被引量:1
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作者 刘艳杰 陆江银 +2 位作者 李玲 武晓峰 崔彦斌 《过程工程学报》 CAS CSCD 北大核心 2018年第3期563-569,共7页
在环氧树脂中添加多壁碳纳米管和膨胀石墨作为填料,以提高环氧树脂的导热性能.结果表明,添加0.5wt%多壁碳纳米管时,环氧树脂的最佳导热系数为0.3448 W/(m×K),比不添加时提高30%;添加0.75wt%羧基改性多壁碳纳米管时,环氧树脂的最... 在环氧树脂中添加多壁碳纳米管和膨胀石墨作为填料,以提高环氧树脂的导热性能.结果表明,添加0.5wt%多壁碳纳米管时,环氧树脂的最佳导热系数为0.3448 W/(m×K),比不添加时提高30%;添加0.75wt%羧基改性多壁碳纳米管时,环氧树脂的最佳导热系数为0.3813 W/(m·K),比添不加时提高40%;同时添加多壁碳纳米管和膨胀石墨后,环氧树脂导热系数可进一步提高到0.4039 W/(m·K),表明在环氧树脂中添加混合填料,二者可在环氧树脂中形成有效的导热网络,能进一步提高聚合物的导热性能. 展开更多
关键词 聚合物 多壁碳纳米管 膨胀石墨 复合材料 导热系数
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Preparation of ChlL-2 and IBDV VP2 Fusion Protein by Baculovirus Expression System 被引量:12
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作者 Yan Liu Yongwei Wei +1 位作者 xiaofeng wu Lian Yu 《Cellular & Molecular Immunology》 SCIE CAS CSCD 2005年第3期231-235,共5页
This study aims to produce an effective subunit vaccine against infectious bursal disease virus (IBDV). The genes of chicken interleukin-2 (ChIL-2) and IBDV viral protein 2 (VP2) were amplified and fused by spli... This study aims to produce an effective subunit vaccine against infectious bursal disease virus (IBDV). The genes of chicken interleukin-2 (ChIL-2) and IBDV viral protein 2 (VP2) were amplified and fused by splice overlap extension-polymerase chain reaction (SOE-PCR). The fusion gene was digested by EcoR I/Kpn I and inserted into pBacPAK8 vector, resulting in recombinant transfer plasmid pBacPakVP2-IL2. The recombinant plasmid was transfected into Sf-9 cells accompanied with hybrid nuclear polyhedrosis virus (HyNPV) genome DNA and lipofectin. Plaque-purification indicated that we had got the recombinant Hy-VP2-IL2. Fusion protein VP2-IL2 was expressed effectively both in insect cells and bombyx mori. The expression of fusion protein was confirmed by ELISA, SDS-PAGE and Western blotting assay, respectively. This efficient system allows us to meet the need for inexpensive vaccines required by the poultry industry. Cellular & Molecular Immunology. 2005;2(3):231-235. 展开更多
关键词 IBDV ChIL-2 fusion gene fusion protein
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Design and synthesis of porous non-noble metal oxides for catalytic removal of VOCs 被引量:4
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作者 Wenxiang Tang Gang Liu +4 位作者 Dongyan Li Haidi Liu xiaofeng wu Ning Han Yunfa Chen 《Science China Chemistry》 SCIE EI CAS CSCD 2015年第9期1359-1366,共8页
The design and synthesis of highly active non-noble metal oxide catalysts, such as transition- and rare-earth-metal oxides, have attracted significant attention because of their high efficiency and low cost and the re... The design and synthesis of highly active non-noble metal oxide catalysts, such as transition- and rare-earth-metal oxides, have attracted significant attention because of their high efficiency and low cost and the resultant potential applications for the degradation of volatile organic compounds(VOCs). The structure-activity relationships have been well-studied and used to facilitate design of the structure and composition of highly active catalysts. Recently, non-noble metal oxides with porous structures have been used as catalysts for deep oxidation of VOCs, such as aromatic hydrocarbons, aliphatic compounds, aldehydes, and alcohols, with comparable activities to their noble metal counterparts. This review summarizes the growing literature regarding the use of porous metal oxides for the catalytic removal of VOCs, with emphasis on design of the composition and structure and typical synthetic technologies. 展开更多
关键词 金属氧化物催化剂 贵金属氧化物 挥发性有机物 多孔结构 成分设计 合成技术 挥发性有机化合物 高活性催化剂
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Tracing of dye molecules in living plants through NaGdF_4:Yb^(3+),Er^(3+)fluorescent nanoprobes 被引量:3
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作者 xiaofeng wu Ya'nan Zhang +9 位作者 Shiping Zhan Jin Li Guozheng Nie Shigang Hu Cong Yan Shaobing wu Shengbin Cheng Junshan Hu Lichun Shi Yunxin Liu 《Journal of Rare Earths》 SCIE EI CAS CSCD 2019年第3期237-241,共5页
In this paper, we demonstrated trace of dye molecules in living plants. The NaGdF4:Yb^(3+),Er^(3+) nanoparticles probe was used to detect the rhodamine B(RhB) in bean sprout. It is found that the fluorescencedye can b... In this paper, we demonstrated trace of dye molecules in living plants. The NaGdF4:Yb^(3+),Er^(3+) nanoparticles probe was used to detect the rhodamine B(RhB) in bean sprout. It is found that the fluorescencedye can be efficiently imbibed during the growing process and the absorbance presented a position dependence effect, which was supported by the upconversion spectra and the fluorescent image characterization. In addition, the concentration of the residual RhB in bean sprout can be efficiently traced by the synthesized probe based on the fluorescent resonant energy transfer. Finally, the relation between the excitation power, concentration and the ratio of yellow to green emission are discussed in detail. These results can be helpful in understanding the RhB dye molecules absorbance process in vegetable growth and provide an efficient way to trace the residual dyes in vivo plant. 展开更多
关键词 Rare-earth-doped materials Biological sensing and sensors Fluorescence Luminescence UPCONVERSION NANOPROBES
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