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Frontiers of Chemical Science and Engineering 2024年第3期18卷 101-112页

作者： Lei Chen Yuan sun Jinshan Chi wei Xiong Pingle Liu Fang Hao College of Chemical Engineering National&Local United Engineering Research Centre for Chemical Process Simulation and IntensificationXiangtan UniversityXiangtan411105China

The selective oxidation of cyclohexane to cyclohexanone and cyclohexanol(KA oil)is a challenging issue in the chemical *** present the industrial conversion of cyclohexane to cyclohexanone and cyclohexanol is normally controlled at less than 5%***,the development of highly active and stable catalysts for the aerobic oxidation of cyclohexane is necessary to overcome this low-efficiency ***,we have developed a cobalt-nitrogen co-doped porous sphere catalyst,Co-NC-x(x is the Zn/Co molar ratio,where x=0,0.5,1,2,and 4)by pyrolyzing resorcinol-formaldehyde resin *** achieved 88.28%cyclohexanone and cyclohexanol selectivity and a cyclohexane conversion of 8.88%under *** results showed that the introduction of zinc effectively alleviated the aggregation of Co nanoparticles and optimized the structural properties of the *** addition,Co0 and pyridinic-N are proposed to be the possible active species,and their proportion efficiently increased in the presence of Zn^(2+)*** this study,we developed a novel strategy to design highly active catalysts for cyclohexane oxidation.

关键词： KA oil production cyclohexane selective oxidation cobalt-nitrogen co-doped porous carbon spheres metal-organic framework

Two-Dimensional Metallophthalocyanine Nanomaterials for Electrocatalytic Energy Conversion

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Energy & Environmental Materials 2024年第4期7卷 364-385页

作者： Xinqi Wang Shaohui sun Jiahao Yao Hao Wan Renzhi Ma wei Ma School of Chemical Engineering and Zhongyuan Critical Metals Laboratory Zhengzhou University Research Center for Materials Nanoarchitectonics (MANA) National Institute for Materials Science (NIMS)

Crowing energy demand drives the rapid development of clean and reliable energy *** the past years,the exploration of novel materials with considerable efficiency and durability has drawn attention in the area of elec... 详细信息

关键词： conjugated nanostructure electrocatalysis 2D metallophthalocyanines

How Does Government Procurement Promote Enterprise Innovation?-On the Synergy between Demand-Pull and Supply-Push of Innovation Policies

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Frontiers of Economics in China-Selected Publications from Chinese Universities 2024年第1期19卷 1-29页

作者： sun wei YE Chusheng Economics and Management School Wuhan UniversityWuhan 430072China Center for Economic Development Research(CEDR) Wuhan UniversityWuhan 430072China

The promotion of technological innovation in firms requires both the supply-push and the *** accurately identify,assess,and further enhance the incentive effects of the policies of government procurement for innovation in China,this paper uses the text analysis method to identify government procurement for innovation from more than 640,000 pieces of government procurement contracts and conducts an empirical analysis based on the data of China's A-share listed firms from 2015 to *** study finds that government procurement for innovation significantly promotes corporate innovation by increasing the expected market returns,reducing R&D uncertainty,and easing financing ***,local government procurement for innovation,central government procurement for innovation,and procurement for innovation by universities and research institutes bring more significant innovation incentives for firms;and government procurement for innovation generates stronger innovation incentives for firms in strategic and emerging industries,private firms,and small-and medium-sized *** analysis reveals that demandside innovation procurement and supply-side innovation subsidies generally have mutually reinforcing synergies on corporate *** policy synergies vary depending on the levels of corporate innovation and the orders of policy *** terms of the levels of corporate innovation,the two-sided policies has mutually complementary effects on innovation-leading firms and mutually exclusive effects on innovation-lagging *** the perspective of the orders of policy implementation,the strategy of supply-side subsidies first,and demand-side procurement second is more effective in promoting corporate innovation than the strategies of demand-side procurement first and supply-side subsidies second,and supply-side subsidies and demand-side procurement *** study helps deepen the understanding of demand-side innovation sup

关键词： government procurement government procurement for innovation corporate innovation innovationpolicy

Prognosis and outcome of intrauterine treatment of fetuses with critical congenital heart disease

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Chinese Medical Journal 2024年第12期137卷 1431-1436页

作者： Liqing Zhao Lei Wang hongping Xia Yurong Wu Xianting Jiao hong Zhu sun Chen Kun sun Department of Pediatric Cardiology Xinhua Hospital Affiliated to Shanghai Jiao Tong University School of MedicineShanghai 200092China Department of Diagnosis and Treatment Center for in utero Pediatric Disease Xinhua Hospital Affiliated to Shanghai Jiao Tong University School of MedicineShanghai 200092China Department of Neonatology Xinhua Hospital Affiliated to Shanghai Jiao Tong University School of MedicineShanghai 200092China

Background:Intrauterine valvuloplasty is an innovative therapy,which promotes ventricular growth and function in some congenital heart diseases(CHDs).The technique remains challenging and can only be performed in a few *** study aimed to assess the feasibility and mid-term outcomes of fetal cardiac intervention(FCI)in fetuses with critical CHD in an experienced tertiary ***:Five fetal aortic valvuloplasty(FAV)or fetal pulmonary valvuloplasty(FPV)procedures were performed in our fetal heart center between August 2018 and May *** success was defined as crossing the aortic or pulmonary valve and balloon inflation,followed by evidence of increased blood flow across the valve and/or new ***-up clinical records and echocardiography were obtained during the prenatal and postnatal ***:Five fetuses received FAV or FPV,including critical aortic stenosis(n=2)and pulmonary atresia with intact ventricular septum(n=3).The mean maternal age was 33.0±2.6 *** median gestational age(GA)at diagnosis was 24 weeks(range,22-26 weeks).The median GA at intervention was 29 weeks(range,28-32 weeks).All five cases underwent successful or partially successful *** patient had pulmonary valve perforation without balloon *** procedure-related deaths or significant complications ***,one neonatal death occurred due to heart and renal *** median follow-up period was 29.5 months(range,8.0-48.0 months).The four surviving patients had achieved biventricular circulation,exhibited improved valve,and ventricular development at the last follow-up ***:Intrauterine FCI could be performed safely with good prognosis in critical CHD.

关键词： Fetal cardiac intervention Valvuloplasty Pulmonary atresia Critical aortic stenosis Congenital heart disease

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Hydrogen production from hydrolysis of NaBH_(4) solution over Co-Fe-B@g-C_(3)N_(4)/NF thin film catalyst

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Rare Metals 2024年第6期43卷 2648-2659页

作者： Yan Wang Jia-Xin Ma Jian Ren Di Zhang Feng-Yan Xu Ke Zhang Zhong-Qiu Cao Qiu-Ju sun Guo-De Li Shi-wei Wu hong-Hui Chen College of Chemistry and Chemical Engineering Shenyang Normal UniversityShenyang 110034China Experimental Center Shenyang Normal UniversityShenyang 110034China Hunan Shande Energy Storage New Materials Research Institute Limited Company Changde 415000China

In this study,the double loaded Co-Fe-B@g-C_(3)N_(4)/NF(NF:Ni foam)thin film catalysts were prepared for the first time via chemical deposition method at room *** optimizing the reducing agent concentration to 0.9 mol·L^(-1),the as-obtained Co-Fe-B@g-C_(3)N_(4)/NF exhibited the twisted ribbon structure with more distinct three-dimensional hierarchy and the smaller particle size,showing the good catalytic property for the hydrolysis of NaBH_(4)*** H_(2)generation rate of Co-Fe-B@g-C_(3)N_(4)/NF and binary Co-B@g-C_(3)N_(4)/NF under visible light irradiation surpassed the value under natural *** apparent activation energy of Co-Fe-B@g-C_(3)N_(4)/NF(45.0 kJ·mol^(-1))under visible light irradiation was obviously reduced when compared with the natural condition(48.4 kJ·mol^(-1))and binary Co-B@g-C_(3)N_(4)/NF(60.6 kJ·mol^(-1))under visible light ***,the catalytic performance of the optimized Co-Fe-B@g-C_(3)N_(4)/NF thin film catalyst was superior to most of the reported non-noble metal and even noble metal ***,it illustrated that the catalytic H_(2)production performance of Co-Fe-B@g-C_(3)N_(4)/NF thin film was distinctly improved after the introduction of light and multicomponent recombination.

关键词： Sodium borohydride Co-Fe-B@g-C_(3)N_(4)/NF catalyst Chemical deposition Hydrogen production

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White Matter Lesions in Young-Middle Aged Migraineurs with Patent Foreman Ovale: A Case-Control Study

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Congenital Heart Disease 2024年第3期19卷 279-291页

作者： Yang Hua Jinyu sun Yuxuan Lou Hao Zhang Jing Shi wei sun Department of Cardiology The First Affiliated Hospital of Nanjing Medical UniversityNanjing210000China

Background:White matter lesion(WML)is common in aging brain and is associated with cognitive impairment and ***,recent studies reported an association between patent foramen ovale(PFO)and WML in migraineurs,especially in young,middle-aged *** retrospective,case-control study aims to describe the clinical characteristics of WML in this population and to explore potential risk ***:226 patients with migraine and PFO were consecutively initially *** factors were selected by the least absolute shrinkage and selection operator(LASSO)regression and multivariable logistic regression model.A Nomogram was employed to visualize the prediction model *** discrimination and calibration abilities were evaluated using the Receiver Operating Characteristic(ROC)curve,the Hosmer-Lemeshow test,and calibration ***:One hundred and nineteen participants were ultimately enrolled in our study,with a median age of 36.9±12.7 years and 80.7%of *** magnetic resonance imaging MRI showed 67(56.3%)patients had WML,whereas 52(43.7%)patients were categorized into the non-WML *** regression screened out potential variables and subsequent multivariate analysisfinally identified age,mean platelet volume,andfibri-nogen(FIB)as independent predictive factors of *** area under the ROC curve(AUC)was ***-mer-Lemeshow test and calibration curve verified a consistency between the predicted and actual ***:The predictive nomogram established and validated in our study may assist clinicians in screening WML among young middle-aged migraineurs with PFO and developing individualized preventive and treatment strategies.

关键词： White matter lesion migraine patent foreman ovale nomogram predictive model

Design and construction of size-controlled CoO/CS catalysts for Fischer–Tropsch synthesis

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Nano Research 2024年第4期17卷 2520-2527页

作者： wei sun Ting Kuang Guiyou wei Yue Li Yaqin Liu Shuai Lyu Yuhua Zhang Jinlin Li Li Wang Key Laboratory of Catalysis and Energy Materials Chemistry of Ministry of Education&Hubei Key Laboratory of Catalysis and Materials Science South-Central Minzu UniversityWuhan 430074China Hubei Key Laboratory of Biomass Fibers and Eco-dyeing&Finishing College of Chemistry and Chemical EngineeringWuhan Textile UniversityWuhan 430200China

The use of supported Co-based catalysts is widespread in various catalytic reactions due to their unique *** structural sensitivity of these catalysts is closely linked to their particle size and crystal ***,comprehending the structure–activity relationship requires the development of well-defined Co-based ***,we employed a colloidal wet chemical process and a heterogeneous nucleation method to prepare well-defined Co-based catalysts supported by inert carbon *** nanospheres’surface possesses abundant functional groups that efficiently capture metal complexes and facilitate the nucleation and growth of CoO *** adjusting the Co source concentration,solvent molar ratio,and nucleation growth kinetics,we successfully prepared CoO/carbon sphere(CS)catalysts with different particle sizes and crystal *** influence of metallic face-centered cubic(fcc)-Co^(0) particle size in the range of 6.6–17.6 nm on the performance of Fischer–Tropsch synthesis(FTS)using well-defined CoO/CS catalysts has been *** result demonstrated that the turnover frequency(TOF)remained constant for CoO/CS catalysts with metallic fcc-Co^(0) particle size larger than 7.7 ***,both the selectivity and the activity changed for CoO/CS catalysts with smaller particles(<7.7 nm).Significantly,when metallic fcc-Co^(0) particle size was reduced from 17.6 to 7.7 nm,the cobalt time yield increased to 6.7μmolCO·gCo^(-1)·s^(-1),indicating improved catalytic *** the same time,the CH_(4) selectivity decreased to 4.9%,suggesting a higher preference for hydrocarbon *** findings demonstrate the importance of particle size in Co catalyzed Fischer–Tropsch *** use of well-defined CoO/CS catalysts offers valuable insights into the structure–activity relationship,leading to a better understanding of Co catalyzed Fischer–Tropsch synthesis.

关键词： Fischer–Tropsch synthesis(FTS) cobalt size effects phase effects carbon nanospheres

Fluorescent carbon dots synthesized in solid phase and air for application in LEDs

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Nano Research 2024年第9期17卷 8495-8503页

作者： wei-Jie Zheng Zhao-Nan sun Yi-Ming Wang Huan-Ming Xiong Department of Chemistry and Shanghai Key Laboratory of Molecular Catalysis and Innovative Materials Fudan UniversityShanghai 200438China

Carbon dots(CDs)have been widely adopted as optical materials because of their excellent luminescent ***,most of the reported synthetic methods are conducted in solvents,especially hydrothermal/solvothermal reactions,leading to intractable problems such as toxic and flammable solvents,complex and inseparable by-products,and dangerously high pressures and ***-phase synthesis of CDs in air is an effective solution to overcome the above issues,but solid reactions always result in uncontrolled growth and agglomeration of *** this study,some inorganic salts are selected as catalysts for synthesizing CDs in solid states and air,which also play as dispersants to hinder CDs *** the meantime,some aromatic derivatives containing hydroxyl and amino groups are chosen as carbon sources,ground with the optimized catalyst,and then heated together in *** production yields are affected by the reaction time and reactant ratio,while the graphitization degrees of the CDs are determined by the reaction *** IG/ID value of their Raman spectra increases from 0.59 to 0.85,and the particle size decreases from 2.5 to 1.4 nm when the synthesis temperature is increased from 200 to 280℃.The as-prepared CDs show emission peaks ranging from 366 to 606 nm,with the photoluminescence(PL)quantum yield up to 53%.Their emission color variation mainly results from different carbon sources,which can be ascribed to the differences in the element composition,functional groups,and graphitic nitrogen content of these *** dispersing CDs of different concentrations into polyvinyl alcohol(PVA)and combining them with blue LEDs,cold,standard,and warm white light emitting devices(WLEDs)are prepared,with a color rendering index(CRI)up to *** the as-prepared CDs have antioxidant ability at high temperature,the as-prepared WLEDs have long lifespans,remaining the effective white luminescence after 72 h continuous work.

关键词： carbon dot solid-phase synthesis white LED photoluminescence inorganic salt catalysis

Sedimentary systems of the Oligocene Huagang Formation in the central anticline zone of the Xihu Depression,East China Sea Shelf Basin

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Energy Geoscience 2024年第1期5卷 275-282页

作者： Wenbo Zheng Guofeng Yin Li sun Shuijian wei Xiuping wei Bo Niu Petroleum Exploration and Production Research Institute of SINOPEC Beijing100083China Shanghai Offshore Oil&Gas Branch SINOPECShanghai200120China

The Xihu Depression is the largest hydrocarbon-bearing depression of the East China Sea Shelf Basin(also referred to as the ECSSB).However,the depositional systems and reservoir distribution of the Oligocene Huagang Formation in the Xihu Depression are still *** the guidance of sedimentology and stratigraphy,this study documented a marine-terrestrial transitional environment in the restricted bay setting of the Oligocene Huagang Formation through core description,well logging,and seismic data *** study also revealed that the Oligocene Huagang Formation is dominated by tidal delta,estuary,and gravity flow deposits in the central anticline zone of the Xihu *** new understanding of the sedimentary systems and the discovery of the transgressive gap in the eastern Diaoyu Islands uplift explain the origin of fine-grained sediments and the EW-trending sand bodies in the central depression and the sand bodies parallel to shoreline in the west slope belt,which cannot be explained by previous study results,such as southern transgression or fluvial deltas and even lacustrine ***,the tidal channels,tidal sand flats,and gravity flow sand bodies formed by the transgressive tides are high-quality *** study will provide a basis for well placement and serve as guidance for the selection of favorable hydrocarbon exploration areas in the Xihu Depression.

关键词： Estuary Sedimentary system Oligocene Huagang Formation Central anticline Xihu Depression East China Sea Shelf Basin

The Spatiotemporal Distribution Characteristics of Cloud Types and Phases in the Arctic Based on CloudSat and CALIPSO Cloud Classification Products

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Advances in Atmospheric Sciences 2024年第2期41卷 310-324页

作者： Yue sun Huiling YANG Hui XIAO Liang FENG wei CHENG Libo ZHOU weixi SHU Jingzhe sun Key Laboratory of Cloud-Precipitation Physics and Severe Storms(LACS) and Department of Lower Atmospheric Observation Research(LAOR)Institute of Atmospheric PhysicsChinese Academy of SciencesBeijing 100029China College of Earth Sciences University of Chinese Academy of Sciences(UCAS)Beijing 100049China Beijing Institute of Applied Meteorology Beijing 100029China

The cloud type product 2B-CLDCLASS-LIDAR based on CloudSat and CALIPSO from June 2006 to May 2017 is used to examine the temporal and spatial distribution characteristics and interannual variability of eight cloud types(high cloud, altostratus, altocumulus, stratus, stratocumulus, cumulus, nimbostratus, and deep convection) and three phases(ice,mixed, and water) in the Arctic. Possible reasons for the observed interannual variability are also discussed. The main conclusions are as follows:(1) More water clouds occur on the Atlantic side, and more ice clouds occur over continents.(2)The average spatial and seasonal distributions of cloud types show three patterns: high clouds and most cumuliform clouds are concentrated in low-latitude locations and peak in summer;altostratus and nimbostratus are concentrated over and around continents and are less abundant in summer;stratocumulus and stratus are concentrated near the inner Arctic and peak during spring and autumn.(3) Regional averaged interannual frequencies of ice clouds and altostratus clouds significantly decrease, while those of water clouds, altocumulus, and cumulus clouds increase significantly.(4) Significant features of the linear trends of cloud frequencies are mainly located over ocean areas.(5) The monthly water cloud frequency anomalies are positively correlated with air temperature in most of the troposphere, while those for ice clouds are negatively correlated.(6) The decrease in altostratus clouds is associated with the weakening of the Arctic front due to Arctic warming, while increased water vapor transport into the Arctic and higher atmospheric instability lead to more cumulus and altocumulus clouds.

关键词： CloudSat and CALIPSO cloud type cloud phase temporal and spatial distribution interannual variation

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