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Optoelectronics Letters 2024年第3期20卷 135-141页

作者： PAN honggang ZHANG Bo SONG Dianyou chen Zhipan chen Chunqi LI Rupeng School of Integrated Circuit Science and Engineering Tianjin University of TechnologyTianjin 300384China

In this paper, an actively Q-switched wavelength injection locking random fiber laser(RFL) based on random phase-shifted fiber Bragg grating(RPS-FBG) is proposed, and the performance of the laser is verified by experiments. Within the reflection bandwidth range of RPS-FBG, spanning from 1 549.2 nm to 1 549.9 nm, different laser modes with stable central wavelength and peak power can be selectively chosen by varying the injected light wavelength. The power fluctuation within 1 h is less than 0.1 d Bm, and the central wavelength drift is less than 0.02 nm. When the pump power increases from 90 mW to 300 mW, the pulse width decreases from 3.2 μs to 1.5 μs, and the pulse repetition frequency is 20 kHz. The RFL can reach a stable locking state at the lowest pump power of 100 mW and the lowest injection power of 3 d Bm. When the wavelength is locked, the output pulse is a single pulse. On the contrary, the unlocked output pulse is multi-pulse. The laser has the characteristics of high wavelength tunability in the reflection range of RPS-FBG and it can be an ideal light source in the fields of laser imaging and pulse coding.

关键词： fiber switched modulator

d-d Orbital coupling induced by crystal-phase engineering assists acetonitrile electroreduction to ethylamine

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Journal of Energy Chemistry 2024年第2期89卷 216-225,I0006页

作者： honggang Huang Yao chen Hui Fu Cun chen Hanjun Li Zhe Zhang Feili Lai Shuxing Bai Nan Zhang Tianxi Liu Key Laboratory of Synthetic and Biological Colloids Ministry of EducationSchool of Chemical and Material EngineeringJiangnan UniversityWuxi 214122JiangsuChina Department of Chemistry KU LeuvenCelestijnenlaan 200FLeuven 3001Belgium College of Chemistry and Chemical Engineering Qingdao UniversityQingdao 266071ShandongChina

The d-d orbital coupling induced by crystal-phase engineering can effectively adjust the electronic structure of electrocatalysts,thus showing significant catalytic performance,while it has been rarely explored in electrochemical acetonitrile reduction reaction(ARR)to date.Herein,we successfully realize the structural transformation of Pd Cu metallic aerogels(MAs)from face-centered cubic(FCC)to body-centered cubic(BCC)through annealing treatment.Specifically,the BCC Pd Cu MAs exhibit excellent ARR performance with high ethylamine selectivity of 90.91%,Faradaic efficiency of 88.60%,yield rate of 316.0 mmol h^(-1)g^(-1)_(Pd+Cu)and long-term stability for consecutive electrolysis within 20 h at-0.55 V vs.reversible hydrogen electrode,outperforming than those of FCC Pd Cu MAs.Under the membrane electrode assembly system,BCC Pd Cu MAs also demonstrate excellent ethylamine yield rate of 389.5 mmol h^(-1)g^(-1)_(Pd+Cu).Density functional theory calculation reveals that the d-d orbital coupling in BCC Pd Cu MAs results in an evident correlation effect for the interaction of Pd and Cu sites,which boosts up the Cu sites electronic activities to enhance ARR performance.Our work opens a new route to develop efficient ARR electrocatalysts from the perspective of crystalline structure transformation.

关键词： d-d Orbital coupling Crystal-phase engineering Metallic aerogels Acetonitrile electroreduction reaction Ethylamine

Recent advances in chemical protein synthesis:method developments and biological applications

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Science China Chemistry 2024年第4期67卷 1060-1096页

作者： Suwei Dong Ji-Shen Zheng Yiming Li Huan Wang Gong chen Yongxiang chen Gemin Fang Jun Guo Chunmao He honggang Hu Xuechen Li Yanmei Li Zigang Li Man Pan Shan Tang Changlin Tian Ping Wang Bian Wu Chuanliu Wu Junfeng Zhao Lei Liu State Key Laboratory of Natural and Biomimetic Drugs and School of Pharmaceutical SciencesPeking UniversityBeijing 100191China Division of Life Sciences and Medicine University of Science and Technology of ChinaHefei 230027China School of Food and Biological Engineering Engineering Research Center of Bio-processMinistry of EducationHefei University of TechnologyHefei 230009China School of Chemistry and Chemical Engineering Nanjing UniversityNanjing 210023China State Key Laboratory of Elemento-Organic Chemistry Nankai UniversityTianjin 300071China Department of Chemistry Tsinghua UniversityBeijing 100084China Institute of Health Sciences Anhui UniversityHefei 230601China College of Chemistry Central China Normal UniversityWuhan 430079China School of Chemistry and Chemical Engineering South China University of TechnologyGuangzhou 510640China School of Medicine or Institute of Translational Medicine Shanghai UniversityShanghai 200444China Department of Chemistry The University of Hong KongHong Kong 999077China Shenzhen Graduate School Peking UniversityShenzhen 518055China School of Chemistry and Chemical Engineering Shanghai Jiao Tong UniversityShanghai 200240China School of Life Sciences University of Science and Technology of ChinaHefei 230026China Department of Chemical Biology Shanghai Jiao Tong UniversityShanghai 200240China Institute of Microbiology Chinese Academy of SciencesBeijing 100101China Department of Chemistry Xiamen UniversityXiamen 361005China School of Pharmaceutical Science Guangzhou Medical UniversityGuangzhou 511436China

The central dogma of modern biology underscores the pivotal roles proteins play in diverse biological processes,the study of which necessitates advanced methods to produce proteins with precision and versatility.Chemical protein synthesis,a powerful approach utilizing chemical reactions for the de novo construction of structurally accurate proteins,has emerged as a transformative tool for studying proteins and generating protein derivatives/mimics inaccessible by natural biological machinery,including post-translationally modified proteins,proteins comprised of unnatural amino acids,as well as mirror-image proteins.This review summarizes recent strides in synthetic method developments for chemical protein synthesis,including innovative techniques in solid-phase peptide synthesis,the challenges presented by difficult sequences in either synthesis or folding and the exploration of novel ligation reactions using both chemical and enzymatic methods.Furthermore,the review also delves into newly developed protocols for site-selective protein modifications and the generation of stapled or macrocyclized peptides/miniproteins,highlighting the power of chemical methods to make structurally diverse proteins.Recent applications of synthetic proteins in investigating post-translational modifications(phosphorylation,lipidation,glycosylation,ubiquitination,etc.),mirror-image biological processes and drug development are further discussed.Together,these topics provide a comprehensive overview of the current landscape of chemical protein synthesis.

关键词： chemical protein synthesis solid-phase peptide synthesis ligation reactions post-translational modifications mirror-image proteins peptide drugs

基于B型深孔测斜曲线的滑坡滑动面位置确定方法

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自然灾害学报 2024年第1期33卷 162-174页

作者：陈浩吴红刚兰州理工大学土木工程学院甘肃兰州730070 中铁西北科学研究院有限公司甘肃兰州730070

在实际的深孔位移监测中,测斜曲线的突变特征是滑动面辨识的关键依据,对于“B”型测斜曲线通常是将曲线的鼓包凸起点作为滑动面的位置,但这种方法容易受到测点布置间隔和横纵坐标观测尺度的影响,存在滑面位置定义不清晰、数值不确定的... 详细信息

在实际的深孔位移监测中,测斜曲线的突变特征是滑动面辨识的关键依据,对于“B”型测斜曲线通常是将曲线的鼓包凸起点作为滑动面的位置,但这种方法容易受到测点布置间隔和横纵坐标观测尺度的影响,存在滑面位置定义不清晰、数值不确定的问题。为了能够有效地克服这些缺点,提升测斜曲线滑动面辨识的准确度,基于“B”型测斜曲线变化特征,研究将滑坡抽象为由“滑动体”、“滑动区间”以及“不动体”三者组成的概化模型,并对滑坡运动过程中不同深度处土体的位移速率和加速度变化特点进行了深入分析。结果表明:土体位移速率沿深度方向会形成多道曲线簇,且不同曲线簇分别对应各滑面所在的滑动区间及非滑动区间。此外,将位移速率转化为加速度,则土体加速度曲线具有更加显著的分簇特征,能够为准确区分滑动体和不动体的区间范围提供重要依据。进一步地,提取监测期内加速度曲线分簇特征显著的当日土体加速度并绘制散点图,能够快速准确地确定坡体不同区间的深度范围。基于当日各滑面所在滑动区间内的加速度数据,运用三次样条插值法计算该区间内的位移加速度最大值,由于滑面处的土体加速度最大,则该值对应的土体深度可作为滑面位置的计算深度。研究方法能够更加精准地确定滑动面位置,并使滑面位置的确定可计算化,有效提升了深孔位移监测数据的利用程度和可靠度,具有较大的实用价值。

关键词：测斜曲线滑动面位置相对位移拐点计算三次样条插值法

Optimizing side chains on different nitrogen aromatic rings achieving 17% efficiency for organic photovoltaics

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Journal of Energy Chemistry 2022年第2期31卷 173-178页

作者： Zhe Li Can Zhu Jun Yuan Liuyang Zhou Wei Liu Xinxin Xia c Juan Hong honggang chen Qingya Wei Xinhui Lu Yongfang Li Yingping Zou College of Chemistry and Chemical Engineering Central South UniversityChangsha 410000HunanChina CAS Key Laboratory of Organic Solids Institute of Chemistry Chinese Academy of SciencesBeijing 100000China Department of Physics The Chinese University of Hong KongHong Kong 999077China

Balancing charge generation and low energy loss(E_(loss)), especially in the wide spectral absorption region is critical to obtain high-performance organic photovoltaics(OPVs). Therefore, Y11-M and Y11-EB are designed and synthesized through modifying alkyl chains on different nitrogen aromatic rings of the reported non-fullerene acceptor Y11. Although all the molecules have almost similar low band-gap(around 1.30 e V), Y11-M and Y11-EB exhibit wider absorption in 410–870 nm region. Eventually, the conventional devices based on Y11-M and Y11-EB possess more efficient charge generation with low Eloss(around 0.44 e V). In addition, outstanding efficiencies of 16.64% and 17.15% with the fill factor of 76.15% and 74.73% are obtained in PM6:Y11-M and PM6:Y11-EB-based devices, both higher than Y11:PM6. The results highlight the importance of rational alkyl chains optimization, and a good structureproperty relationship is established as well.

关键词： Fused-ring benzotriazole Side chains modification Low band-gap acceptors High-efficiency organic photovoltaics

CO_2 adsorption performance of different amine-based siliceous MCM-41 materials

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Journal of Energy Chemistry 2015年第3期24卷 322-330页

作者： Zhilin Liu Yang Teng Kai Zhang honggang chen Yongping Yang Beijing Key Laboratory of Emission Surveillance and Control for Thermal Power Generation North China Electric Power University

A series of amine-based adsorbents were synthesized using siliceous MCM-41 individually impregnated with four different amines（ethylenediamine（EDA）,diethylenetriamine（DETA）,tetraethylenepentamine（TEPA） and pentaethylenehexamine（PEHA）） to study the effect of amine chain length and loading weight on their CO2 adsorption performances in detail.The adsorbents were characterized by FT-IR,elemental analysis,and thermo-gravimetric analysis to confirm their structure properties.Thermo-gravimetric analysis was also used to evaluate the CO2 adsorption performance of adsorbents.Longer chain amine-based materials can achieve higher amine loadings and show better thermal stability.The CO2 adsorption capacities at different temperatures indicate that the CO2 adsorption is thermodynamically controlled over EDAMCM41 and DETA-MCM41,while the adsorption over TEPA-MCM41 and PEHA-MCM41 is under kinetic control at low temperature.The chain length of amines affects the CO2 adsorption performance and the adsorption mechanism significantly.The results also indicate that CO2 adsorption capacity can be enhanced despite of high operation temperatures,if appropriate amines（TEPA and PEHA） are applied.However,adsorbents with short chain amine exhibit higher adsorption and desorption rates due to the collaborative effect of rapid reaction mechanisms of primary amines and less diffusion resistance of shorter chain length amines.

关键词： amine-based MCM-41 CO2adsorption chain length adsorption mechanism diffusion mechanism

A-DA′D-A non-fullerene acceptors for high-performance organic solar cells

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Science China Chemistry 2020年第10期63卷 1352-1366页

作者： Qingya Wei Wei Liu Mario Leclerc Jun Yuan honggang chen Yingping Zou College of Chemistry and Chemical Engineering Central South UniversityChangsha 410083China Department of Chemistry Universite LavalQuebec CityQuebec G1V 0A6Canada

Since the world-record power conversion efficiency of 15.7%was achieved for organic solar cells(OSCs)in 2019,the newly developed non-fullerene acceptor(NFA)Y6 with an A-DA′D-A structure(A denotes an electron-accepting moiety,D denotes an electron-donating moiety)has attracted increasing attention.Subsequently,many new A-DA′D-A NFAs have been designed and synthesized,and the A-DA′D-A NFAs have played a significant role in the development of high-performance non-fullerene organic solar cells(NF-OSCs).Compared with the classical A-D-A-type acceptors,A-DA′D-A NFAs contain an electrondeficient core(such as benzothiadiazole(BT),benzotriazole(BTA),quinoxaline(Qx),or their derivatives)in the ladder-type fused rings to fine-tune the energy levels,broaden light absorption and achieve higher electron mobility of the NFAs.This review emphasizes the recent progress on these emerging A-DA′D-A(including Y-series)NFAs.The synthetic methods of DA′D-fused rings are introduced.The relationships between the chemical structure of the A-DA′D-A NFAs and the photovoltaic performance of the corresponding OSCs are summarized and discussed.Finally,issues and prospects for further improving photovoltaic performance of the OSCs are also proposed.

关键词： organic solar cells A-DA′D-A non-fullerene acceptors electron-deficient core photovoltaic properties

Molecular size characterization of heavy oil fractions in vacuum and solution by molecular dynamic simulation

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Frontiers of Chemical Science and Engineering 2010年第3期4卷 250-256页

作者： Wenpo REN honggang chen Chaohe YANG Honghong SHAN State Key Laboratory of Heavy Oil Processing China University of PetroleumQingdao 266555China

Two kinds of heavy oils were fractionated into eight fractions by Liquid-Solid Adsorption Chromatography,respectively,and samples were collected to measure properties.According to the elemental analysis,molecular weight and 1H-NMR data,average molecular structures of polycyclic aromatic and heavy resin were constructed with improved Brown-Ladner(B-L)method and several corrections.And then,the most stable conformations of polycyclic aromatic and heavy resin in vacuum and toluene solution were obtained by molecular dynamic simulation,and the molecular size was gotten via the radius of gyration analysis.The results showed that the radius of gyration of polycyclic aromatic and heavy resin was 0.55-0.70 nm in vacuum and 0.60-0.90 nm in toluene solution.With molecular weight increasing,the molecular size in vacuum and toluene solution also increased.Due to the swelling behavior of solvent,the alkyl side chains of heavy oil molecule in solution were more stretched.Thus,the molecular size in toluene solution was larger than that in vacuum.

关键词： heavy oil molecular size radius of gyration molecular dynamic simulation

Ternary solvent-processed efficient organic solar cells based on a new A-DA'D-A acceptor derivative employing the 3^(rd)-position branching side chains on pyrroles

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Chinese Chemical Letters 2021年第1期32卷 229-233页

作者： Yu chen honggang chen Huilan Guan Wei Liu Zhe Li Hui Liu Yongfang Li Yingping Zou College of Chemistry and Chemical Engineering Central South UniversityChangsha 410083China School of Materials Science and Engineering Zhengzhou UniversityZhengzhou 450001China Institute of Chemistry Chinese Academy of SciencesBeijing 100190China

Recent advances in non-fullerene acceptors(NFAs),typically Y6,have driven power conversion efficiency(PCE) of single-junction orga nic solar cells(OSCs) over 16%.Mea nwhile,it becomes essential to know how to adopt simple strategies to further improve device performance.In this work,a new A-DA'D-A acceptor derivative,Y19-N3 employing 3-ethylheptyl branched at the 3^(rd)-position instead of 2-ethylhexyl on the pyrroles of Y19 is reported.The selection of an appropriate solvent in casting device is implemented to maximize the photovoltaic performance.PBDB-T:Y19-N3-based OSCs treated with a ternary solvent of CF/CB(1:3,v/v) and 0.8% DIO exhibit the optimal PCE of 13.77% here,with the significantly improved V_(oc)(0.78 V) and FF(0.72) as well as the high J_(sc)(24.46 mA/cm^(2)).Further characterizations indicate that this ternary solvent-treated PBDB-T/Y19-N3 film exhibits the more appropriate morphological features with the highly efficient charge generation and collection as well as the more balanced electron and hole mobilities.This work combines molecular design and device engineering to improve the photovoltaic properties,which is important to the development of OSCs.

关键词： Organic solar cells Side chain engineering Ternary solvent Increased efficiency Balanced mobilities

基于DEMATEL-VIKOR的水电站绿色运行水平评价与提升路径

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小水电 2024年第3期 3-5,34页

作者：陈红刚中国水电基础局有限公司天津市301700

水电站在推动经济社会发展、保障能源安全、促进环境保护等方面具有重要作用。为促进水电站的绿色发展,应用DEMATEL-VIKOR方法构建了水电站绿色运行水平评价模型,并对J水电站的绿色运行水平进行评价。研究结果表明,J水电站绿色运行水平... 详细信息

水电站在推动经济社会发展、保障能源安全、促进环境保护等方面具有重要作用。为促进水电站的绿色发展,应用DEMATEL-VIKOR方法构建了水电站绿色运行水平评价模型,并对J水电站的绿色运行水平进行评价。研究结果表明,J水电站绿色运行水平评价结果为“良好”,环境和社会维度评价结果为“良好”,治理维度评价结果为“一般”,为提高绿色运行水平,应注重节能减排,关注社会效益,优化管理措施。表2个。

关键词：水电站绿色运行水平 DEMATEL VIKOR 提升路径