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High efficiency and selectivity catalyst for photocatalytic oxidative coupling of methane

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Chinese Journal of Structural Chemistry 2023年第12期42卷 1-2页

作者： qijun tang Wenguang Tu Yong Zhou Zhigang Zou School of Science and Engineering The Chinese University of Hong KongShenzhenGuangdong518172PR China Jiangsu Key Laboratory for Nano Technology National Laboratory of Solid State MicrostructuresCollaborative Innovation Center of Advanced MicrostructuresSchool of PhysicsNanjing UniversityNanjing210093PR China

Methane(CH_(4))holds great promise in replacing oil as a building block for chemical commodities[1].However,due to the low-polar nature and high C-H bond energy(439 kJ/mol)of CH_(4),the conversion of CH_(4)by traditional thermocatalysis requires harsh reaction conditions(*** temperature and high pressure)and thus,is energy-consuming[2].To be worse,the production of undesired products like CO_(2)is unavoidable as a result of hydrocarbon combustion reactions[2].

关键词： holds consuming methane

Flexible planar micro supercapacitor diode

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Journal of Energy Chemistry 2024年第6期93卷 429-435,I0011页

作者： Yihui Ma Pei tang Zhenyuan Miao Wuyang Tan qijun Wang Yuecong Chen Guosheng Li Qingyun Dou Xingbin Yan Lingling Shui Guangdong Basic Research Center of Excellence for Structure and Fundamental Interactions of Matter Guangdong Provincial Key Laboratory of Nanophotonic Functional Materials and DevicesSchool of Information and Optoelectronic Science and Engineering&South China Academy of Advanced OptoelectronicsGuangzhou 510006GuangdongChina Department of Materials Science and Engineering Sun Yat-Sen UniversityGuangzhou 510275GuangdongChina College of Materials Science and Engineering Guilin University of TechnologyGuilin 541004GuangxiChina

Supercapacitor diode is a novel ion device that performs both supercapacitor energy storage and ion diode rectification ***,previously reported devices are limited by their large size and complex *** this work,we demonstrate a screen-printed micro supercapacitor diode(MCAPode)that based on the insertion of a finger mode with spinel ZnCo_(2)O_(4) as cathode and activated carbon as anode for the first time,and featuring an excellent area specific capacitance(1.21 mF cm^(-2)at 10 mV s^(-1))and high rectification characteristics(rectification ratioⅠof 11.99 at 40 mV s^(-1)).Taking advantage of the ionic gel electrolyte,which provides excellent stability during repeated flexing and at high *** addition,MCAPode exhibits excellent electrochemical performance and rectification capability in"AND"and"OR"logic *** findings provide practical solutions for future expansion of micro supercapacitor diode applications.

关键词： Micro devices Supercapacitor diodes Screen-printing Rectification Logic gates

Enhanced CH4 selectivity in CO2 photocatalytic reduction over carbon quantum dots decorated and oxygen doping g-C3N4

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Nano Research 2019年第11期12卷 2749-2759页

作者： Qian Li Songcan Wang Zhuxing Sun qijun tang Yiqiu Liu Lianzhou Wang Haiqiang Wang Zhongbiao Wu Key Laboratory of Environment Remediation and Ecological Health Ministry of EducationCollege of Environmental and Resources ScienceZhejiang UniversityHangzhou 310058China Zhejiang Provincial Engineering Research Center of Industrial Boiler and Furnace Flue Gas Pollutin Control Hangzhou 311202China Nanomaterials Centre School of Chemical Engineering and Australian Institute for Bioengineering and NanotechnologyThe University of QueenslandBrisbaneQLD 4072Australia Schoo of Envionmental Science and Engineering Shanghai Jiao Tong UniversityShanghai 200240China

Graphitic carbon nitride(g-C3N4,CN)exhibits inefficient charge separation,deficient CO2 adsorption and activation sites,and sluggish surface reaction kinetics,which have been recognized as the main barriers to its application in CO2 photocatalytic *** this work,carbon quantum dot(CQD)decoration and oxygen atom doping were applied to CN by a facile one-step hydrothermal *** incorporated CQDs not only facilitate charge transfer and separation,but also provide alternative CO2 adsorption and activation ***,the oxygen-atom-doped CN(OCN),in which oxygen doping is accompanied by the formation of nitrogen defects,proves to be a sustainable H^+ provider by facilitating the water dissociation and oxidation *** of the synergistic effect of the hybridized binary CQDs/OCN addressing the three challenging issues of the CN based materials,the performance of CO2 photocatalytic conversion to CH4 over CQDs/OCN-x(x represents the volume ratio of laboratory-used H2O2(30 wt.%)in the mixed solution)is dramatically improved by 11 times at *** hybrid photocatalyst design and mechanism proposed in this work could inspire more rational design and fabrication of effective photocatalysts for CO2 photocatalytic conversion with a high CH4 selectivity.

关键词： photocalytic CO2 reduction graphitic carbon nitride(g-C3N4) carbon quantum dot oxygen doping

构建半人工光合系统实现可见光驱动专性有机卤化物呼吸菌去除三氯乙烯

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科学通报 2022年第34期67卷 4108-4115页

作者：唐晴唐麒君羊家威陈柯蓁王海强沈超峰浙江大学环境与资源学院杭州310058 浙江省水体污染控制与环境安全技术重点实验室杭州310058

发展新型绿色、高效、低能耗和可持续的微生物修复技术用于处理氯代烯烃污染十分必要.专性有机卤化物呼吸菌能专一高效地去除氯代有机污染物,但在实际修复过程中电子供体如氢气的不足限制了其应用,因此寻找合适的供氢方式十分重要.利用... 详细信息

发展新型绿色、高效、低能耗和可持续的微生物修复技术用于处理氯代烯烃污染十分必要.专性有机卤化物呼吸菌能专一高效地去除氯代有机污染物,但在实际修复过程中电子供体如氢气的不足限制了其应用,因此寻找合适的供氢方式十分重要.利用光催化水解产氢为微生物提供电子供体可能是一种理想方式,然而国内外尚未有半人工光合系统驱动微生物脱卤呼吸的相关研究.本文利用脱卤拟球菌Dehalococcoides mccartyi菌株195(Dhc195)与硼掺杂石墨相氮化碳纳米片构建了B-C3N4-NS-Dhc195生物杂化体系,探究可见光驱动其对三氯乙烯(TCE)进行厌氧还原脱氯的可行性.研究结果表明,在(25±5) W m^(-2)的低强度可见光下该生物杂化体系可持续稳定地将TCE逐步还原脱氯至乙烯(ETH),脱氯速率为(1.13±0.13)μmol L^(-1)d^(-1);该杂化体系内检测到氢气生成,对Dhc195脱氯的用氢量进行衡算,其氢气利用率达84%.这表明可见光下光催化剂分解水产氢,脱氯菌利用氢气作为电子供体还原TCE,从而实现可见光驱动微生物脱卤呼吸.本研究提出了一种间接利用光能实现微生物处理氯代有机污染物的方法,对氯代有机污染物的绿色、低碳、可持续治理和修复具有启发意义.

关键词：光催化三氯乙烯脱卤拟球菌还原脱氯生物杂化体系

Real-world effectiveness of early insulin therapy on the incidence of cardiovascular events in newly diagnosed type 2 diabetes

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Signal Transduction and Targeted Therapy 2024年第7期9卷 2953-2959页

作者： Sihui Luo Xueying Zheng Wei Bao Sheng Nie Yu Ding Tong Yue Yilun Zhou Ying Hu Hua Li Qiongqiong Yang qijun Wan Bicheng Liu Hong Xu Guisen Li Gang Xu Chunbo Chen Huafeng Liu Yongjun Shi Yan Zha Yaozhong Kong Guobin Su Ying tang Mengchun Gong Linong Ji Fan Fan Hou Jianping Weng Department of Endocrinology First Affiliated Hospital of USTCDivision of Life Sciences and MedicineUniversity of Science and Technology of ChinaHeifeiChina Institute of Public Health Sciences Division of Life Sciences and MedicineUniversity of Science and Technology of ChinaHefeiChina Division of Nephrology National Clinical Research Center for Kidney DiseaseState Key Laboratory of Organ Failure ResearchNanfang HospitalSouthern Medical UniversityGuangzhouChina Department of Nephrology Beijing Tiantan HospitalCapital Medical UniversityBeijingChina The Second Affiliated Hospital of Zhejiang University School of Medicine HangzhouChina Sir Run Run Shaw Hospital Zhejiang University School of MedicineHangzhouChina Department of Nephrology Sun Yat-Sen Memorial HospitalSun Yat-Sen UniversityGuangzhouChina The Second People’s Hospital of Shenzhen Shenzhen UniversityShenzhenChina Institute of Nephrology Zhongda HospitalSoutheast University School of MedicineNanjingChina Children’s Hospital of Fudan University ShanghaiChina Renal Department and Institute of Nephrology Sichuan Provincial People’s HospitalSchool of MedicineUniversity of Electronic Science and Technology of ChinaSichuan Clinical Research Center for Kidney DiseasesChengduChina Division of Nephrology Tongji HospitalTongji Medical CollegeHuazhong University of Science and TechnologyWuhanChina Department of Critical Care Medicine Maoming People’s HospitalMaomingChina Key Laboratory of Prevention and Management of Chronic Kidney Disease of Zhanjiang City Institute of NephrologyAffiliated Hospital of Guangdong Medical UniversityZhanjiangChina Huizhou Central People’s Hospital Sun Yat-Sen UniversityHuizhouChina Guizhou Provincial People’s Hospital Guizhou UniversityGuiyangChina Department of Nephrology the First People’s Hospital of FoshanFoshanChina Department of Nephrology Guangdong Provincial Hospital of Chinese Medicinethe Second Affiliated Hospitalthe Second Clinical CollegeGuangzhou University of Chinese Medicin

Early insulin therapy is capable to achieve glycemic control and restoreβ-cell function in newly diagnosed type 2 diabetes(T2D),but its effect on cardiovascular outcomes in these patients remains *** this nationwide real-world study,we analyzed electronic health record data from 19 medical centers across China between 1 January 2000,and 26 May *** included 5424 eligible patients(mean age 56 years,2176 women/3248 men)who were diagnosed T2D within six months and did not have prior cardiovascular *** Cox regression models were used to estimate the associations of early insulin therapy(defined as the first-line therapy for at least two weeks in newly diagnosed T2D patients)with the incidence of major cardiovascular events including coronary heart disease(CHD),stroke,and hospitalization for heart failure(HF).During 17,158 persons years of observation,we documented 834 incident CHD cases,719 stroke cases,and 230 hospitalized cases for *** diagnosed T2D patients who received early insulin therapy,compared with those who did not receive such treatment,had 31%lower risk of incident stroke,and 28%lower risk of hospitalization for *** significant difference in the risk of CHD was *** found similar results when repeating the aforesaid analysis in a propensity-score matched population of 4578 patients and with inverse probability of treatment weighting *** findings suggest that early insulin therapy in newly diagnosed T2D may have cardiovascular benefits by reducing the risk of incident stroke and hospitalization for HF.

关键词： cardiovascular treatment nationwide

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旋挖钻机施工过程分析及其控制策略研究

机电工程 2023年第12期40卷 1907-1914页

作者：许祥唐琦军任凯张大庆周恩怀湖南农业大学机电工程学院湖南长沙410128 山河智能装备股份有限公司国家级企业技术中心湖南长沙410100 湖南大学重庆研究院重庆401135

旋挖钻机具备施工速度快、成孔质量高、环境污染较小等特点。但由于施工工艺的多样性、地质条件的多变性和复杂的质量控制要求,旋挖钻机面临施工效率和燃油消耗等诸多挑战。为了提高旋挖钻机的施工效率,降低整机的燃油消耗,开展了旋挖... 详细信息

旋挖钻机具备施工速度快、成孔质量高、环境污染较小等特点。但由于施工工艺的多样性、地质条件的多变性和复杂的质量控制要求,旋挖钻机面临施工效率和燃油消耗等诸多挑战。为了提高旋挖钻机的施工效率,降低整机的燃油消耗,开展了旋挖钻机施工过程的试验研究。首先,根据旋挖钻机的工作特点,将其工作过程分为下钻钻进、钻杆上提、上车回转、卸渣过程、回转对孔等5个阶段;然后,分析了各工作阶段旋挖钻机和发动机性能参数的变化规律;最后,为了使旋挖钻机各阶段的发动机工作状态保持最优,提出了基于钻杆最大进尺速度的发动机转速控制策略,开发了控制程序,实现了在旋挖钻机工作过程中对发动机转速的精准控制目的,该研究已在生产厂家试验现场的实际钻机上进行了验证,并与安装在钻机上的车载监测系统的数据进行了对比。研究结果表明:采用新的控制策略可以使发动机工作在最佳的状态,整机工作效率提高了15%,整机油耗降低了5.74%;将该方法应用在旋挖钻机实际工作过程中时,具有操作难度低、稳定性强的特点,能够有效提高旋挖钻机作业过程的效率,降低整机的燃油消耗。

关键词：工程机械旋挖钻机施工效率发动机过程控制转速控制策略

钯化学态对g-C3N4光催化还原CO2的影响:单原子态在促进CH4生成中的独特作用(英文)

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Chinese Journal of Catalysis 2023年第3期46卷 177-190页

作者：李钱唐麒君熊珮瑶陈东之陈建孟吴忠标王海强浙江大学环境与资源学院污染环境修复与生态健康教育部重点实验室浙江海洋大学石油化工与环境学院临港石油天然气储运技术国家地方联合工程研究中心浙江省石油化工环境污染控制重点实验室浙江省工业锅炉炉窑烟气污染控制工程技术研究中心

化石燃料过度消耗引起的CO2过量排放和能源短缺问题日益突出.利用太阳能和光催化剂将CO2转化成高附加值化学原料,可以同时缓解温室效应与能源短缺,是实现“碳中和”与社会可持续发展的有效途径.目前在光催化剂合成方面已取得巨大进步,... 详细信息

化石燃料过度消耗引起的CO2过量排放和能源短缺问题日益突出.利用太阳能和光催化剂将CO2转化成高附加值化学原料,可以同时缓解温室效应与能源短缺,是实现“碳中和”与社会可持续发展的有效途径.目前在光催化剂合成方面已取得巨大进步,但由于电荷重组严重,表面反应动力学迟缓, CO2还原效率仍普遍偏低.助催化剂修饰是改善催化剂催化CO2还原效率的有效策略.贵金属是提升催化剂性能最显著的一类助催化剂,然而其资源有限,优格昂贵,将贵金属助催化剂的尺寸减小至单原子,可以最大限度地提高原子利用率,大幅降低成本,显著提升催化剂的催化性能.现有研究在揭示贵金属助催化剂性能提升机制时,主要集中在其对基底材料性质的影响,忽略了单原子态与其它化学价态的区别.因此本文以g-C3N4(CN)纳米片为基底,研究Pd单原子(Pd-SA), PdOx, Pd纳米颗粒(Pd-NP)修饰对CN光催化还原CO2性能的影响及性能提升差异显著的内在机制.利用透射电子显微镜、高角度环形暗场扫描透射电子显微镜、X射线光电子能谱、基于同步辐射的X射线吸收谱等手段确定Pd物种在CN表面的存在形态和化学价态.性能测试结果表明,三种形态Pd修饰均可促进CN光催化还原CO2的性能,但提升效果存在显著差异.Pd/CN-SA上的CH4产量约2.25 μmol/g,明显高于PdOx/CN (1.08 μmol/g), Pd/CN-NP (0.44 μmol/g)和CN (0.104 μmol/g);Pd修饰后, CN的CH4选择性明显提高,其中Pd/CN-SA的CH4选择性高达73.5%,优于PdOx/CN(67.2%)和Pd/CN-NP(60%).光电性质分析结果表明, Pd修饰有效提升了CN的光吸收性能,显著促进了载流子的迁移与分离,且Pd/CN-NP和PdOx/CN的有效光生电子密度较Pd/CN-SA更高,结果说明样品的光电性质不是影响其光催化还原CO2活性的关键因素.CO2-PPD结果表明, Pd/CN-SA表面具有丰富的中等强度的碱性位(HCO3-),更有利于CO2吸附与活化.H+的产生通常伴随着·OH和·O2-的形成,因此根据电子自旋共振获得的·OH和·O2-产量可推测出, Pd/CN-NP可形成最丰富的H+, PdOx/CN次之, Pd/CN-SA最低.H2吸附实验结果表明,在氢溢流效应的影响下, Pd修饰显著促进了CN对H2的吸附,且Pd/CN-SA对H2的吸收量最大,说明H2在Pd-SA表面更易发生解离形成·H,这可能是其CH4产量较高的重要原因.对比了以H2和H2O为还原剂时的CO2光催化还原性能,结果表明, PdOx/CN和Pd/CN-SA的CH4产量分别下降了66.3%和28.6%,Pd/CN-NP的甲烷产量反而提高,说明Pd/CN-NP可能具有较好的·H利用效率,其以H2O为还原剂时的低CH4产量可能受限于·H的形成.为进一步验证该推测,利用DFT模拟研究了H2O分子在Pd/CN-NP, PdOx/CN和Pd/CN-SA表面的吸附解离能,结果表明, H2O分子在Pd/CN-SA表面的活化能最低,最有利于·H的形成.此外,完整的H2O解离反应过程中Pd/CN-NP会释放出0.40 eV能量, Pd/CN-SA与PdOx/CN则需补充额外的能量(0.51和1.47 eV),再次强有力地证明Pd/CN-NP具有较好的·H利用效率.最后,利用原位红外分析了各样品光催化还原CO2反应过程的差异,发现Pd/CN-SA表面的CO2吸附态物种在可见光照射下更容易参与至后续的光催化还原反应中;PdOx/CN和Pd/CN-NP表面的CO2吸附态物种含量足够丰富,但由于它们的光生电子还原能力有限,无法将吸附物种进一步还原;Pd/CN-SA和Pd/CN-NP表面吸附的CO可进一步被还原成甲氧基,但吸附在PdOx/CN表面的CO难以被进一步还原.综上,本文揭示了贵金属Pd的化学价态对CO2还原性能的关键作用,对未来合理设计开发更有效的CO2还原光催化剂具有借鉴意义.

关键词： CO2光催化还原化学价态 Pd g-C3N4 H原子利用

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点火提前角对小缸径高转速汽油机性能的影响

小型内燃机与车辆技术 2022年第6期51卷 13-18页

作者：任凯唐琦军谭绍辉许祥湖南农业大学机电工程学院湖南长沙410128

为了研究点火提前角对小缸径高转速汽油机性能的影响规律,对本田CBR600汽油机开展了试验研究。分别选取了发动机转速为4 000 r/min和8 000 r/min下三种不同节气门开度的工况点,开展了点火提前角在一定范围内变化的台架试验。试验数据表... 详细信息

为了研究点火提前角对小缸径高转速汽油机性能的影响规律,对本田CBR600汽油机开展了试验研究。分别选取了发动机转速为4 000 r/min和8 000 r/min下三种不同节气门开度的工况点,开展了点火提前角在一定范围内变化的台架试验。试验数据表明:在一定范围内增大点火提前角,发动机的功率、转矩、有效热效率增加;排气总管温度、排气总管余热能百分比得到下降;从总的趋势来看,点火提前角的变化对充量系数影响不大。随着点火提前角增大,4 000 r/min转速下,CO排放变化不明显,HC排放小负荷时降低、中大负荷时增加,NO_(x)排放降低;8 000 r/min转速下,CO排放小负荷时降低、中大负荷时增加,HC、NO_(x)排放均增加。

关键词：点火提前角汽油机动力性能经济性能排放性能

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基于转矩模型的柴油机功率在线测试方法研究

农业机械学报 2020年第S2期51卷 571-578页

作者：唐琦军常宏博蒋蘋罗锋郑帅帅湖南农业大学机电工程学院长沙410128 广西玉柴机器股份有限公司玉林537000

针对拖拉机耕作过程柴油机输出功率不易精准测量的问题,基于柴油机燃油控制策略的转矩模型,对雷沃拖拉机在理论速度为5.7 km/h和8.9 km/h的耕地过程的柴油机功率进行了在线测量。将在线测量的指示功率与燃烧分析仪测量的指示功率进行了... 详细信息

针对拖拉机耕作过程柴油机输出功率不易精准测量的问题,基于柴油机燃油控制策略的转矩模型,对雷沃拖拉机在理论速度为5.7 km/h和8.9 km/h的耕地过程的柴油机功率进行了在线测量。将在线测量的指示功率与燃烧分析仪测量的指示功率进行了对比,结果表明:在拖拉机耕作速度较稳定的一段区间内,在线测量的指示功率平均值误差为2.99%,但瞬时值严重失真;分析发现喷油量和喷油时刻的变化是引起功率测量偏差较大的主要原因。为了提高柴油机输出功率在线测量的精准度,利用GTPower模型得到了该柴油机12个典型工况的空燃比和喷油时刻与转矩的定量关系,并提出利用喷油量修正系数和喷油时刻修正系数对在线测量方法进行修正。优化后方法的测试结果表明:拖拉机稳定运行阶段柴油机功率平均值误差为0.88%,瞬时值误差明显改善。

关键词：柴油机功率测量转矩模型试验