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Investigation of L/D-threonine substituted L-serine octamer ions by mass spectrometry and infrared photodissociation spectroscopy

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Chinese Chemical Letters 2017年第3期28卷 537-540页

作者： Juan Ren Yi-Yun Wang Ru-Xia Fenga xiang-lei kong The State Key Laboratory of Elemento-Organic Chemistry Nankai University Tianjin 300071 China Collaborative Innovation Center of Chemical Science and Engineering Nankai University Tianjin 300071 China

Threonine-substituted serine octamer ions were generated by electrospray ionization（ESI） and investigated by mass spectrometry and infrared photodissociation（IRPD） spectroscopy. IRPD spectra of[L-Ser_7＋ L/D-Thr_1]H~＋and [L-Ser_6＋ L/D-Thr_2]H~＋were obtained in the range of 2700–3600 cm^（-1）. Chiral differentiation was achieved by comparing their IRPD spectra. The main difference located in the range of 3300–3500 cm^（-1）. And the results indicate the substitution of L-Ser by D-Thr could weaken the intermolecular H-bonds and loosen the original structures of serine octamers.

关键词： IRPD spectroscopy Threonine Serine octamer Chiral differentiation Mass spectrometry

Structure of Protonated Heterodimer of Proline and Phenylalanine:Revealed by Infrared Multiphoton Dissociation Spectroscopy and Theoretical Calculations

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Chinese Journal of Chemical Physics 2020年第5期33卷 590-594,I0029-I0038,I0079页

作者： Juan Ren Xian-yi Zhang xiang-lei kong State Key Laboratory of Elemento-organic Chemistry College of ChemistryNankai UniversityTianjin 300071China School of Physics and Electronic Information Anhui Normal UniversityAnhui Normal UniversityWuhu 241000China Collaborative Innovation Center of Chemical Science and Engineering Nankai UniversityTianjin 300071China

The infrared multiphoton dissociation(IRMPD)spectrum of the protonated heterodimer of Pro Phe H+,in the range of 2700-3700 cm^-1,has been obtained with a Fourier-transform ion cyclotron mass spectrometer combined with an IR OPO *** experimental spectrum shows one peak at 3565 cm^-1 corresponding to the free carboxyl O-H stretching vibration,and two broad peaks centered at 2935 and 3195 cm^-*** calculations were performed on the level of M062 X/6-311++G(d,p).Results show that the most stable isomer is characterized by a charge-solvated structure in which the proton is bound to the unit of *** predicted spectrum is in good agreement with the experimental one,although the coexistence of salt-bridged structures cannot be entirely excluded.

关键词： Infrared multiphoton dissociation spectroscopy Mass spectrometry Heterodimer Amino acids

Clustering of major cardiovascular risk factors is associated with arterial stiffness in adults

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慢性疾病与转化医学(英文) 2018年第4期4卷 254-259页

作者： xiang-lei kong Xiao-Jing Ma Cheng-Yin Zhang Dong-Mei Xu Department of Nephrology Qianfoshan Hospital Shandong University Department of Health Examination Center Qianfoshan Hospital Shandong University Department of Nephrology Yidu Central Hospital Weifang Medical College

Objective: Cardiovascular disease(CVD) is the leading cause of mortality and morbidity *** studies have indicated that clustering of major CVD risk factors is *** aimed to explore the association of clustering of CVD risk factors with arterial stiffness in ***: A total of 9984 adults were *** investigated clustering of four major CVD risk factors(defined as two or more of the following: hypertension, diabetes, dyslipidemia, and high body mass index) and their association with arterial *** stiffness was evaluated using the carotid-femoral pulse wave velocity(cfPWV).Results: In the study group(52.2% men, the mean age was 55.4 ± 10.5 years; only 11.9% of participants were free of any pre-defined CVD risk factors and 61.8% of participants had clustering of CVD risk *** cfPWV was significantly higher in the clustered risk factors group than in the no risk factor or the single risk factor groups(16.1 ± 3.1, 13.4 ± 2.2, and 14.3 ± 2.6 m/s, respectively;P<0.001).Multiple linear regression analysis revealed that age, gender, clustering of CVD risk factors, serum uric acid, and decreased renal function positively correlated with *** a categorical outcome, the highest cfPWV quartile(cfPWV≥16.9 m/s) was compared with the lower three *** adjusting for potential confounders, clustering of CVD risk factors significantly correlated with increased cfPWV compared with that in the no risk factor group, with an odds ratio of 5.76(95% confidence interval:4.46-7.44).Conclusions: Clustering of CVD risk factors significantly correlated with arterial stiffness; this confirms the importance of lifestyle modification to reduce the burden of CVD.

关键词： Arterial stiffness Cardiovascular disease Cluster Pulse wave velocity

Association of hemoglobin with arterial stiffness evaluated by carotid-femoral pulse wave velocity among Chinese adults

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Chronic Diseases and Translational Medicine 2019年第2期5卷 122-128页

作者： Zhen-Zhen Zhang Ping Wang xiang-lei kong Wen-Li Mao Mei-Yu Cui Taishan Medical University Tai'an Shandong 271000 China Department of Nephrology Qianfoshan Hospital Affiliated to Shandong University Jinan Shandong 250014 China

Objective: Increased hemoglobin (Hb) levels are known to be associated with increased cardiovascular events and mortalities. Therefore, we assumed that high Hb levels were associated with arterial stiffness. Pulse wave velocity (PWV) is a simple and noninvasive method for measuring arterial stiffness to assess cardiovascular disease in general populations. Accordingly, we conducted a cross-sectional study to explore the association of Hb with PWV. Methods: A total of 6642 adults aged 54.5 ± 11.2 years undergoing physical examinations were enrolled, 71.7% of whom were males. Arterial stiffness was evaluated by carotid-femoral PWV (cfPWV). Multivariable regression analyses were performed to determine the relationship between Hb and increased cfPWV. Results: In this study, the mean Hb (per 10 g/L increase) was 144.7 ± 13.9 g/L, and the mean cfPWV was 15.1 ± 3.1 m/s. cfPWV was significantly higher in high hemoglobin groups >15.4 g/L (Quartile 4) than in the lowest hemoglobin group (Quartile 1 < 13.6 g/L;P < 0.001). Multiple linear regression analysis revealed that Hb positively correlated with cfPWV (β= 0.16, P < 0.01). Univariate Logistic regression analysis revealed that Hb was associated with increased cfPWV, with an odd ratio (OR) of 1.46 (95% confidence interval [CI], 1.39-1.54). After adjusting for potential confounders, Hb and the highest Hb quartile group were also independently associated with increased cfPWV, with a fully adjusted OR of 1.11 (95% CI, 1.02-1.20) and 1.45 (95% CI, 1.01-2.08), respectively. Conclusion: This study demonstrated that Hb levels significantly correlate with increased cfPWV.

关键词： Hemoglobin Pulse wave velocity Arterial stiffness Cardiovascular diseases

元素周期表中元素单晶基于局域密度理论的正电子寿命计算

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物理学报 2009年第11期58卷 7627-7632页

作者：陈祥磊孔伟杜淮江叶邦角中国科学技术大学近代物理系合肥230026

在局域密度近似理论(LDA)的基础上用中性原子叠加模型和有限插分方法(SNA-FD)计算了元素周期表中各种元素单晶的正电子体寿命和单空位寿命.分析了不同结构的单晶中自由正电子的分布信息和湮没信息.元素单晶的正电子寿命计算值与文献中... 详细信息

在局域密度近似理论(LDA)的基础上用中性原子叠加模型和有限插分方法(SNA-FD)计算了元素周期表中各种元素单晶的正电子体寿命和单空位寿命.分析了不同结构的单晶中自由正电子的分布信息和湮没信息.元素单晶的正电子寿命计算值与文献中的实验测量值相符合,表明LDA基础上的SNA-FD方法可以作为单晶中正电子湮没理论计算的有效研究手段.

关键词：局域密度近似理论正电子寿命

Relationship between occult hepatitis B virus infection and chronic kidney disease in a Chinese population-based cohort

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Chronic Diseases and Translational Medicine 2016年第1期2卷 -页

作者： xiang-lei kong a c Xiao-Jing Ma b Hong Su a Dong-Mei Xu a a Department of Nephrology Qianfoshan Hospital Shandong University No.16766 Jingshi Road Jinan China b Department of Health Examination Center Qianfoshan Hospital Shandong University No.16766 Jingshi Road Jinan China

Objective: Previous studies have revealed inconsistent results regarding the association between occult hepatitis B virus (HBV) infection and chronic kidney disease (CKD). Therefore, we conducted a prospective cohort study to evaluate the association be-tween occult HBV infection and CKD. Methods: A total of 4329 adults, aged 46.2 ± 13.7 years, without CKD at baseline were enrolled while undergoing physical examinations. Occult HBV infection was defined as seropositivity for antibody to HBV core antigen. CKD was defined as decreased estimated glomerular filtration rate (eGFR0.05). After adjustment for potential confounders in the multivariate Logistic regression analysis, age, hypertension, diabetes, and the highest quartile of uric acid were associated with CKD, with ORs of 1.04 (95%CI:1.02e1.05), 2.1 (95%CI:1.46e3.01), 2.02 (95%CI:1.36e2.99), and 1.86 (95%CI:1.17e2.95), respectively. However, occult HBV infection was not associated with CKD, with an OR of 1.12 (95%CI:0.65e1.95). Conclusions: This study did not find an association between occult HBV infection and CKD. However, high-risk patients infected with HBV should still be targeted for monitoring for the development of CKD.

关键词： Chronic kidney disease Proteinuria Estimated glomerular filtration rate Hepatitis B virus

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Micro-strain regulation strategy to stabilize perovskite lattice based on the categories and impact of strain on perovskite solar cells

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Journal of Energy Chemistry 2025年第1期100卷 578-604页

作者： Caixia Li Wenwu Liu Shiji Da Lingbin kong Fen Ran State Key Laboratory of Advanced Processing and Recycling of Nonferrous Metals Lanzhou University of Technology School of Materials Science and Engineering Lanzhou University of Technology

Photovoltaic metal halide perovskite solar cells(PSCs) convert light to electricity more efficiently than crystalline silicon cells, and the cost of materials used to make them is lower than that of silicon *** efficiency is not a core issue affecting the application of perovskite solar cells in special *** present, stability is the major technical encounters that hinders its further commercial development. Microstrain in PSCs is currently a significant factor responsible for the device's instability. Strain-induced ion migration is widely believed to accelerate perovskite degradation even when external stimuli are ***, it is imperative to study strain to enhance the stability of PSCs. This paper reviews recent developments to understand strain's origin and effect mechanisms on performance of PSCs, including ion migration,failure behavior, defect formation, and its effect on photoelectric properties, stability, and ***, several well-known strain management strategies are systematically introduced based on the strain effect mechanism and strain engineering on the film, providing more clues for further preparation with increased stability. The manipulation of external physical strain applied from films to entire devices has been extensively studied. Furthermore, recommendations for future research directions and chemical approaches have been provided. It is emphasized that strain engineering plays a crucial role in improving the efficiency and longevity of PSCs. Tensile strain causes rapid degradation, while moderate compressive strain and external strain control could improve properties and stability. Efforts should focus on controlling compressive strain to mitigate residual tensile strain and introducing it in a controlled manner. Future research endeavors may focus on exploring these pathways to improve the efficiency and lifespan of PSCs.

关键词： Halide perovskite solar cells Strain origins Strain effects Strain management

Dynamic Interaction Analysis of Coupled Axial-Torsional-Lateral Mechanical Vibrations in Rotary Drilling Systems

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Structural Durability & Health Monitoring 2025年第1期19卷 77-103页

作者： Sabrina Meddah Sid Ahmed Tadjer Abdelhakim Idir kong Fah Tee Mohamed Zinelabidine Doghmane Madjid Kidouche Applied Automation Laboratory Faculty of Hydrocarbons and ChemistryUniversity of BoumerdesBoumerdes35000Algeria Institute of Electrical and Electronic Engineering(IGEE) University of BoumerdesBoumerdes35000Algeria Laboratory of the Electrification of Industrial Enterprises University of BoumerdesBoumerdes35000Algeria Electrical Engineering Department Mohamed Boudiaf University of M’silaM’sila28000Algeria Department of Civil and Environmental Engineering King Fahd University of Petroleum&MineralsDhahran31261Saudi Arabia Interdisciplinary Research Center for Construction and Building Materials King Fahd University of Petroleum&Minerals(KFUPM)Dhahran31261Saudi Arabia

Maintaining the integrity and longevity of structures is essential in many industries,such as aerospace,nuclear,and *** achieve the cost-effectiveness of large-scale systems in petroleum drilling,a strong emphasis on structural durability and monitoring is *** study focuses on the mechanical vibrations that occur in rotary drilling systems,which have a substantial impact on the structural integrity of drilling *** study speciﬁcally investigates axial,torsional,and lateral vibrations,which might lead to negative consequences such as bit-bounce,chaotic whirling,and high-frequency *** events not only hinder the efﬁciency of drilling but also lead to exhaustion and harm to the system’s components since they are difﬁcult to be detected and controlled in real *** study investigates the dynamic interactions of these vibrations,speciﬁcally in their high-frequency modes,usingﬁeld data obtained from measurement while ***ﬁndings have demonstrated the effect of strong coupling between the high-frequency modes of these vibrations on drilling sys-tem *** obtained results highlight the importance of considering the interconnected impacts of these vibrations when designing and implementing robust control ***,integrating these compo-nents can increase the durability of drill bits and drill strings,as well as improve the ability to monitor and detect ***,by exploiting theseﬁndings,the assessment of structural resilience in rotary drilling systems can be ***,the study demonstrates the capacity of structural health monitoring to improve the quality,dependability,and efﬁciency of rotary drilling systems in the petroleum industry.

关键词： Rotary drilling systems mechanical vibrations structural durability dynamic interaction analysis ﬁeld data analysis

The School that Changes Mindsets

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China Today 2025年第1期74卷 62-64页

作者： GUO QING kong SIQI 不详

China’s highest-altitude primary school is not only teaching children of farmers and herders but their parents as *** Sinopec Primary School in Nagqu,a city in Xizang Autonomous Region in southwest China,is known as the school“the closest to the sky”due to its high-altitude location-a breathtaking 4,700 meters above sea *** by oil and gas giant Sinopec as part of its corporate social responsibility,the school opened in 2012 and has since become a microcosm of China’s drive for education,especially in remote and rural areas,to ensure that no one is left behind.

关键词： altitude farmers southwest