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Transition metal anchored on C_(9)N_(4) as a single-atom catalyst for CO_(2) hydrogenation: A first-principles study

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Chinese Physics B 2022年第10期31卷 520-528页

作者： jia-liang chen Hui-jia Hu Shi-Hao Wei Department of Microelectronic Science and Engineering School of Physical Science and TechnologyNingbo UniversityNingbo 315211China Department of Electronic and Information Engineering School of Electrical Engineering and Computer ScienceNingbo UniversityNingbo 315211China

To alleviate the greenhouse effect and maintain the sustainable development, it is of great significance to find an efficient and low-cost catalyst to reduce carbon dioxide(CO_(2)) and generate formic acid(FA). In this work, based on the first-principles calculation, the catalytic performance of a single transition metal(TM)(TM = Cr, Mn, Fe, Co, Ni, Cu, Zn,Ru, Rh, Pd, Ag, Cd, Ir, Pt, Au, or Hg) atom anchored on C_(9)N_(4) monolayer(TM@C_(9)N_(4)) for the hydrogenation of CO_(2) to FA is calculated. The results show that single TM atom doping in C_(9)N_(4) can form a stable TM@C_(9)N_(4) structure, and Cu@C_(9)N_(4) and Co@C_(9)N_(4) show better catalytic performance in the process of CO_(2) hydrogenation to FA(the corresponding maximum energy barriers are 0.41 eV and 0.43 e V, respectively). The partial density of states(PDOS), projected crystal orbital Hamilton population(p COHP), difference charge density analysis and Bader charge analysis demonstrate that the TM atom plays an important role in the reaction. The strong interaction between the 3d orbitals of the TM atom and the non-bonding orbitals(1πg) of CO_(2) allows the reaction to proceed under mild conditions. In general, our results show that Cu@C_(9)N_(4) and Co@C_(9)N_(4) are a promising single-atom catalyst and can be used as the non-precious metals electrocatalyst for CO_(2) hydrogenation to formic acid.

关键词： first-principles calculation CO_(2)hydrogenation catalysts electronic structure reaction mechanisms reaction paths

Single boron atom anchored on graphitic carbon nitride nanosheet(B/g-C_(2)N)as a photocatalyst for nitrogen fixation:A first-principles study

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Chinese Physics B 2021年第8期30卷 287-294页

作者： Hao-Ran Zhu jia-liang chen Shi-Hao Wei Department of Microelectronic Science and Engineering School of Physical Science and TechnologyNingbo UniversityNingbo 315211China College of Electronic Information and Optical Engineering Nankai UniversityTianjin 300350China

It is essential to explore high efficient catalysts for nitrogen reduction in ammonia *** on the first-principles calculation,we find that B/g-C_(2)N can serve as high performance photocatalyst in N_(2)fixation,where single boron atom is anchored on the g-C_(2)N to form B/g-C_(2)*** the introduction of B atom to g-C_(2)N,the energy gap reduces from 2.45 eV to 1.21 eV and shows strong absorption in the visible light *** addition,N_(2)can be efficiently reduced on B/g-C_(2)N through the enzymatic mechanism with low onset potential of 0.07 V and rate-determining barrier of 0.50 ***"acceptance-donation"interaction between B/g-C_(2)N and N_(2)plays a key role to active N_(2),and the BN_(2)moiety of B/g-C_(2)N acts as active and transportation *** activity originates from the strong interaction between 1π1π*orbitals of N_(2)and molecular orbitals of B/g-C_(2)N,the ionization of 1πorbital and the filling of 1π*orbital can increase the N≡N bond length greatly,making the activation of N_(2).Overall,this work demonstrates that B/g-C_(2)N is a promising photocatalyst for N_(2)fixation.

关键词： first-principles calculation N_(2)reduction catalysts electronic structure reaction mechanisms reaction paths

Big Theta Equals Small Theta Generically

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Acta Mathematica Sinica,English Series 2024年第3期40卷 717-730页

作者： Rui chen jia liang ZOU Institute for Advanced Study in Mathmatics Zhejiang UniversityHangzhou 310058P.R.China Department of Mathematics University of Michigan530 Church StAnn ArborMI 48109USA

In this paper we consider the theta correspondence over a non-Archimedean local *** the homological method and the theory of derivatives,we show that under a mild condition the bigtheta lift is irreducible.

关键词： Theta correspondence derivatives

Effect of particle size on the microstructure and thermal conductivity of Al/diamond composites prepared by spark plasma sintering

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Rare Metals 2009年第6期28卷 646-650页

作者： CHU Ke jia chengchang liang Xuebing chen Hui GAO Wenji School of Material Science and Engineering University of Science and Technology Beijing Beijing 100083 China

Spark plasma sintering （SPS） was used to fabricate Al/diamond composites. The influence of diamond particle size on the microstructure and thermal conductivity （TC） of composites was investigated by combining experimental results with model prediction. The results show that both composites with 40 pan particles and 70 μm particles exhibit high density and good TC, and the composite with 70 μm particles indicates an excellent TC of 325 W.m^-1.K^-1. Their TCs lay between the theoretical estimated bounds. In contrast, the composite with 100 lain particles demonstrates low density as well as poor TC due to its high porosity and weak interfacial bonding. Its TC is even considerably less than the lower bound of the predicted value. Using larger diamond particles can further enhance thermal conductive performance only based on the premise that highly dense composites of strong interfacial bonding can be obtained.

关键词： metal matrix composites thermal properties sintering particle size

Spin-orbit interaction induced Casimir-Lifshitz torque between two-dimensional electron gases

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Science China(Physics,Mechanics & Astronomy) 2024年第8期67卷 134-142页

作者： jia-Nan Rong liang chen Kai Chang State Key Laboratory of Superlattices and Microstructures Institute of SemiconductorsChinese Academy of SciencesBeijing 100083China School of Mathematics and Physics North China Electric Power UniversityBeijing 102206China School of Physics Zhejiang UniversityHangzhou 310027China College of Materials Science and Opto-electronic Technology University of Chinese Academy of SciencesBeijing 100049China

We investigate theoretically the Casimir interaction between two parallel two-dimensional electron gases(2DEGs)with Rashba and Dresselhaus spin-orbit interactions(SOIs),based on the quantum field *** derive an analytical expression for the polarization tensor and obtain the solution to the motion equation of the electromagnetic(EM)*** calculate the CasimirLifshitz torque(CLT)between two parallel 2DEGs with Rashba and Dresselhaus SOIs,which can be tuned by changing the relative strength between two *** anisotropic Casimir energy between 2DEGs caused by the interplay between the SOIs of 2DEGs offers a new origin of CLT and a new type of optoelectronic device.

关键词： Casimir torque two-dimensional electron gas spin-orbit interaction

Effects of recombinant human growth hormone on growth of human gastric carcinoma xenograft model in nude mice

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World Journal of Gastroenterology 2006年第24期12卷 3810-3813页

作者： Dao-Ming liang jia-Yong chen Yi Zhang Ping Gan Jie Lin An-Bao chen Department of Emergency Surgery of the SecondAffiliated Hospital Kunming Medical College Kunming 650101Yunnan Province China

AIM： To study effects of recombinant human growth hormone （rhGH） on growth of a human gastric carcinoma cell in vivo. METHODS： Experimental mice were divided into control group, rhGH group, oxaliplatin （L-OHP） group and rhGH＋L-OHP group. Cultured human gastric carcinoma cells BGC823 were inoculated into right axilla of nude mice and carcinoma xenograft model was established successfully. Inhibitory rate of xenograft tumor growth was estimated by measuring tumor volume; expression of proliferating cell nuclear antigen （PCNA）, Bax and Bcl-2 proteins of xenograft tumor was detected using immunohistochemical S-P method. RESULTS： Tumor growth inhibitory rate, the positive expression rate of PCNA, Bax and Bcl-2 were 49.3%, 58.2%, 65.2% and 59.2% in rhGH＋L-OHP group respectively; 46.6%, 62.5%, 59.7% and 64.7% in L-OHP group; 5.0%, 82.7%, 23.2% and 82.2% in rhGH group and 0, 77.8%, 23.5% and 80.3% in control group. There was significant difference between rhGH＋L-OHP group （or L-OHP group ） and control group or rhGH group （P 〈 0.05）, whereas there were no significant differences （P 〉 0.05） between L-OHP group and rhGH＋L-OHP group and between rhGH group and control group. CONCLUSION： rhGH does not accelerate the proliferation of human gastric cancer cell in vivo.

关键词： Human growth hormone Stomach neoplasm Nude mice

Prevalence and risk factors of osteoporosis detected by dual-energy X-ray absorptiometry among Chinese patients with primary biliary cholangitis

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World Journal of Gastroenterology 2023年第29期29卷 4580-4592页

作者： jia-liang chen Yao Liu Yu-Fei Bi Xian-Bo Wang Center of Integrative Medicine Beijing Ditan HospitalCapital Medical UniversityBeijing 100015China

BACKGROUND Osteoporosis is an extrahepatic complication of primary biliary cholangitis(PBC)that increases the risk of fractures and ***,Epidemiological studies of osteoporosis in patients with PBC in China and the Asia-Pacific region is *** To assess the prevalence and clinical characteristics of osteoporosis in Chinese patients with *** This retrospective analysis included consecutive patients with PBC from a tertiary care center in China who underwent bone mineral density(BMD)assessment using dual-energy X-ray absorptiometry between January 2013 and December *** defined subjects with T-scores≤-2.5 in any sites(L1 to L4,femoral neck,or total hip)as having ***,serological,clinical,and histological data were *** risk factors for osteoporosis were identified by multivariate logistic regression *** A total of 268 patients with PBC[236 women(88.1%);mean age,56.7±10.6 years;163 liver biopsies(60.8%)]were *** overall prevalence of osteoporosis in patients with PBC was 45.5%(122/268),with the prevalence of osteoporosis in women and men being 47.0%and 34.4%,*** prevalence of osteoporosis in postmenopausal women was significantly higher than that in premenopausal women(56.3%vs 21.0%,P<0.001).Osteoporosis in patients with PBC is associated with age,fatigue,menopausal status,previous steroid therapy,body mass index(BMI),splenomegaly,gastroesophageal varices,ascites,Mayo risk score,histological stage,alanine aminotransferase,albumin,bilirubin,platelet and prothrombin *** regression analysis identified that older age,lower BMI,previous steroid therapy,higher Mayo risk score,and advanced histological stage as the main independent risk factors for osteoporosis in *** Osteoporosis is very common in Chinese patients with PBC,allowing for prior screening of BMD in those PBC patients with older age,lower BMI,previous steroid therapy and advanced liver d

关键词： Primary biliary cholangitis Osteoporosis Bone mineral density Dual-energy X-ray absorptiometry Prevalence Chinese

Dication-accelerated anion transport inside micropores for the rapid decontamination of pertechnetate

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Nuclear Science and Techniques 2022年第4期33卷 19-32页

作者： Peng Zhang Yi-Zhi chen Han-Qin Weng Zi-Fang Guo jia-liang chen Xing Zhao Guo-An Ye Ming-Zhang Lin School of Nuclear Science and Technology University of Science and Technology of ChinaHefei 230026China Department of Beam Material Science SANKENThe Institute of Scientific and Industrial ResearchOsaka University8-1 MihogaokaIbarakiOsaka 567-0047Japan Radiochemistry Department of China Institute of Atomic Energy China Institute of Atomic EnergyBeijing 102413China

Over 70%of the treated contaminated water at the Fukushima Daiichi Nuclear Power Station contains radionuclides beyond the regulatory standard for discharge that need to be ***-99(^(99)Tc),mainly in the form of pertechnetate Tc(VII)O_(4)^(-),is one of the main sources of long-term radiotoxicity that jeopardizes the environment and human ***,we used a series of dicationic pyridinium(DCP)derivative groups(–Py^(+)C_(n)H_(2n)N^(+)Me_(3),n=2,3,and 5)to modify commercial Reillex 425 resins containing tertiary pyridyl groups to improve the adsorption performance of rhenium(Re,an analog of radioactive Tc)and *** the quaternary pyridinium and ammonium sites in one DCP group can adsorb ReO_(4)^(-) simultaneously,DCP-modified Reillex 425(Reillex-Cn)exhibited high maximum adsorption capacities for Re under neutral *** capacities reached 344.8,416.7,and 588.2 mg g^(-)1 for Reillex 425-C2,Reillex 425-C3,and Reillex 425-C5,*** diffusion of ReO_(4)^(-)/TcO_(4)^(-) in Reillex 425-Cn was verified to be the rate-limiting step of ***,adsorption can be adjusted by the length of the alkyl spacers between the two positively charged N sites in DCP.–Py^(+)C_(2)H_(4)N^(+)Me_(3) significantly enhanced intraparticle diffusion compared to–Py^(+)C_(5)H_(10)N^(+)Me_(3).The two positive sites in–Py^(+)C_(2)H_(4)N^(+)Me_(3) would be laterally distributed,leading to a smaller steric hindrance for ReO_(4)–/TcO_(4)^(-) transport inside the microporous ***,the longer alkyl spacers in–Py^(+)C_(5)H_(10)N^(+)Me_(3) formed hydrophobic microphases,repulsing the hydrated ReO_(4)–/TcO_(4)^(-) ***,the adsorptions of both ReO_(4)^(-) and TcO_(4)^(-) on Reillex 425-C2 were faster than those on Reillex ***,Reillex 425-Cn exhibited an exothermic nature,good selectivity,excellent reusability,and strong salinity *** study provides a simple strategy to enhance the Tc removal performance

关键词： Quaternary pyridinium Dicationic pyridyl derivatives Pertechnetate Intraparticle diffusion

Development and validation of machine learning models for nonalcoholic fatty liver disease

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Hepatobiliary & Pancreatic Diseases International 2023年第6期22卷 615-621页

作者： Hong-Ye Peng Shao-Jie Duan liang Pan Mi-Yuan Wang jia-liang chen Yi-Chong Wang Shu-Kun Yao Graduate School of Beijing University of Chinese Medicine Beijing 100029China Department of Gastroenterology China-Japan Friendship HospitalBeijing 100029China Phase 1 Clinical Trial Center Deyang People’s HospitalDeyang 618000China School of Public Health Tongji Medical CollegeHuazhong University of Science and TechnologyWuhan 430030China Center of Integrated Traditional Chinese and Western Medicine Beijing Ditan HospitalCapital Medical UniversityBeijing 100102China

Background: Nonalcoholic fatty liver disease(NAFLD) had become the most prevalent liver disease worldwide. Early diagnosis could effectively reduce NAFLD-related morbidity and mortality. This study aimed to combine the risk factors to develop and validate a novel model for predicting NAFLD. Methods: We enrolled 578 participants completing abdominal ultrasound into the training set. The least absolute shrinkage and selection operator(LASSO) regression combined with random forest(RF) was conducted to screen significant predictors for NAFLD risk. Five machine learning models including logistic regression(LR), RF, extreme gradient boosting(XGBoost), gradient boosting machine(GBM), and support vector machine(SVM) were developed. To further improve model performance, we conducted hyperparameter tuning with train function in Python package ‘sklearn’. We included 131 participants completing magnetic resonance imaging into the testing set for external validation. Results: There were 329 participants with NAFLD and 249 without in the training set, while 96 with NAFLD and 35 without were in the testing set. Visceral adiposity index, abdominal circumference, body mass index, alanine aminotransferase(ALT), ALT/AST(aspartate aminotransferase), age, high-density lipoprotein cholesterol(HDL-C) and elevated triglyceride(TG) were important predictors for NAFLD risk. The area under curve(AUC) of LR, RF, XGBoost, GBM, SVM were 0.915 [95% confidence interval(CI): 0.886–0.937], 0.907(95% CI: 0.856–0.938), 0.928(95% CI: 0.873–0.944), 0.924(95% CI: 0.875–0.939), and 0.900(95% CI: 0.883–0.913), respectively. XGBoost model presented the best predictive performance, and its AUC was enhanced to 0.938(95% CI: 0.870–0.950) with further parameter tuning. Conclusions: This study developed and validated five novel machine learning models for NAFLD prediction, among which XGBoost presented the best performance and was considered a reliable reference for early identification of high-risk patients wit

关键词： Nonalcoholic fatty liver disease Machine learning Predictive factors