检索结果-南通市图书馆

Transactions of Tianjin University 2024年第4期30卷 297-304页

作者： Li Li Fanpeng Chen bo-Hang Zhao Yifu yu Institute of Molecular Plus Department of ChemistrySchool of ScienceTianjin UniversityTianjin 300072China

Electrocatalytic semi-hydrogenation of acetylene(C_(2)H_(2))over copper nanoparticles(Cu NPs)offers a promising non-petroleum alternative for the green production of ethylene(C2H4).However,server hydrogen evolution reaction(HER)competition in this process prominently decreases C2H4 selectivity,thereby hindering its practical ***,a Cu-based composite catalyst,wherein porous carbon with nanoscale pores was used as a support,is constructed to gather the C_(2)H_(2) feedstocks for suppressing the undesirable *** a result,the as-prepared catalyst exhibited C_(2)H_(2) conversion of 27.1%and C_(2)H_(4) selectivity of 88.4%at a C2H4 partial current density of 0.25 A/cm^(2) under optimal−1.0 V versus reversible hydrogen electrode(RHE)under the simulated coal-derived C_(2)H_(2) atmosphere,significantly outperforming the single Cu NPs *** addition,a series of in situ and ex situ experimental results show that not only the porous nature of the carbon support but also the stabilized Cu^(0)–Cu^(+) dual active sites through the strong metal–support interactions enhance the adsorption capacity of C_(2)H_(2),leading to high C_(2)H_(2) partial pressure,restraining the HER and thus improving the C2H4 selectivity.

关键词： Electrocatalysis Cu-based catalyst Hydrogenation Ethylene Selectivity

Nonalternant isomer of pentacene fusing two azulene units

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Chinese Chemical Letters 2024年第5期35卷 244-248页

作者： bo yu Pengchen Du Jianwen Guo Hanshen Xin Jianhua Zhang Department of Chemistry College of SciencesShanghai UniversityShanghai 200444China School of Microelectronics Shanghai UniversityShanghai 201800China

Azulene is a promising building block for creating innovative polycyclic aromatic hydrocarbons. This study involved the construction of three nonalternant isomers of pentacene by fusing two azulene units, named Az-PH1/2/3. Az-PH1 was initially developed through the rhodium(Ⅱ)-catalyzed cyclization of bis(N-tosylhydrazone)s. Intriguingly, Az-PH1 was also unexpectedly obtained during a nickel(0)-catalyzed one-step tandem reaction. We investigated the optical and electrochemical properties, aromaticity, and photo-oxidative stability of Az-PH1, comparing it with the well-known pentacene using density functional theory, electrochemical, and photophysical tests. Our results showed that the azulene-fusing strategy resulted in a molecule with narrow optical bandgaps(2.046 eV) and a long half-life time under ambient air conditions.

关键词： Azulene Isomer Polycyclic aromatic hydrocarbon Nickel(0)-catalyzed Photo-oxidative stability

Effect of micro-Al_(2)O_(3) powders on oxidation and corrosion behaviors of low-carbon MgO-C refractories

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Journal of Iron and Steel Research International 2024年第6期31卷 1522-1534页

作者： Yang Chen Zeng-yi Li Hao-bo Tan yu-ran Fu Jun Ding Cheng-ji Deng Chao yu School of Materials Science and Engineering Hunan Institute of TechnologyHengyang 421002HunanChina The State Key Laboratory of Refractories and Metallurgy Wuhan University of Science and TechnologyWuhan 430081HubeiChina

To solve the problem of poor high-temperature service performance caused by low carbonization of MgO-C refractories,low-carbon MgO–C refractories with excellent thermal shock,oxidation and corrosion resistances were successfully designed by using SiC whiskers as reinforcing phases and introducing micro-Al_(2)O_(3) powders as *** results indicated that the addition of micro-Al_(2)O_(3) powders optimized the internal structure of the material,like the columnar β-Si_(3)N_(4) with a stepped distribution and the mosaic structure formed between granular and flaky Mg_(2)SiO_(4),which synergistically strengthened and toughened the material and gave the material excellent mechanical properties and thermal shock ***,the cold modulus of rupture and cold crushing strength after thermal shock were increased by 4.1 and 20.3 MPa,***,the addition of micro-Al_(2)O_(3) powders promoted the formation of fine particles of Mg_(2)SiO_(4),MgAl_(2)O_(4) and MgO,as well as a dense protective layer of Mg_(2)SiO_(4) in the material under high-temperature ***,spinel and high-temperature solid solution were formed in the corrosion *** oxidation and corrosion resistances were greatly improved by 41%and 15%,respectively.

关键词： Low-carbon MgO-C refractory Oxidation resistance Corrosion resistance Thermal shock resistance Micro-Al_(2)O_(3)powder

Dental-derived stem cells in tissue engineering:the role of biomaterials and host response

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Regenerative Biomaterials 2024年第1期3卷 17-26页

作者： Weihao yuan Luiza de Almeida Queiroz Ferreira bo yu Sahar Ansari Alireza Moshaverinia Weintraub Center for Reconstructive Biotechnology Section of ProsthodonticsSchool of DentistryUniversity of CaliforniaLos AngelesLos AngelesCA 90095USA Department of Restorative Dentistry School of DentistryUniversidade Federal de Minas GeraisBelo HorizonteMinas GeraisBrazil Section of Restorative Dentistry School of DentistryUniversity of CaliforniaLos AngelesLos AngelesCA 90095USA Department of Bioengineering Henry Samueli School of Engineering and Applied SciencesUniversity of CaliforniaLos AngelesLos AngelesCA 90095USA

Dental-derived stem cells(DSCs)are attractive cell sources due to their easy access,superior growth capacity and low *** can respond to multiple extracellular matrix signals,which provide biophysical and biochemical cues to regulate the fate of residing ***,the direct transplantation of DSCs suffers from poor proliferation and differentiation toward functional cells and low survival rates due to local ***,elegant advances in the design of novel biomaterials have been made to give promise to the use of biomimetic biomaterials to regulate various cell behaviors,including proliferation,differentiation and *** could be tailored with multiple functionalities,e.g.,*** is an emerging need to summarize recent advances in engineered biomaterials-mediated delivery and therapy of DSCs and their potential ***,we outlined the design of biomaterials for supporting DSCs and the host response to the transplantation.

关键词： dental-derived stem cells biomaterials host response tissue engineering

Unveiling the Contribution of Lactic Acid to the Passivation Behavior of Ti-6Al-4V Fabricated by Laser Powder Bed Fusion in Hank’s Solution

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Acta Metallurgica Sinica(English Letters) 2024年第1期37卷 102-118页

作者： yu-Hang Chu Liang-yu Chen bo-yuan Qin Wenbin Gao Fanmin Shang Hong-yu Yang Lina Zhang Peng Qin Lai-Chang Zhang School of Materials Science and Engineering Jiangsu University of Science and TechnologyZhenjiang212100China Foshan(Southern China)Institute for New Materials Foshan528200China Key Laboratory of Automobile Materials Ministry of Education and Department of Materials Science and EngineeringJilin UniversityChangchun130025China Centre for Advanced Materials and Manufacturing School of EngineeringEdith Cowan University270 Joondalup DriveJoondalupPerthWA6027Australia

In actual physiological environments,bacteria can activate the immune system and release lactic ***,the detailed contribution of lactic acid to the passivation behavior of titanium(Ti)alloys is still *** current work investigated the in vitro passivation behavior of Ti-6Al-4V(TC4)alloys fabricated by laser powder bed fusion in Hank's solution with and without adding lactic *** methods,inductively coupled plasma atomic emission spectrometer,and X-ray photoelectron spectroscopy were jointly *** lactic acid decreases the corrosion resistance of samples by degrading the formed passive *** film formed in the(lactic acid)-containing solution exhibits a higher level of oxygen vacancies and a lower thickness,attributed to the suppressed formation of Ti^(4+)transformed from Ti^(3+)and Ti^(2+).Moreover,the presence of lactic acid would increase the open circuit potential,relieve the ions release,and hinder the deposition of calcium phosphates within 24 h immersion.

关键词： Titanium alloy Corrosion behavior Passive film Lactic acid Laser powder bed fusion

Postoperative pneumocranium after endoscopic transnasal optic canal decompression

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

International Journal of Ophthalmology(English edition) 2024年第5期17卷 973-975页

作者： Sheng-Jian Lu bo yu Wen-Can Wu The Eye Hospital School of Ophthalmology&OptometryWenzhou Medical UniversityWenzhou 325027Zhejiang ProvinceChina

Dear Editor,We present the first time,a case of a patient developed cerebrospinal fluid(CSF)leak and pneumocranium following optic canal decompression(OCD).INTRODUCTION Indirect traumatic optic neuropathy(ITON)impairs visual functions and quality of *** transnasal optic canal decompression(ETOCD)is one of the standard treatment strategies for the *** the ETOCD,the optic nerve sheath are usually incised for sufficient decompression of optic nerve after removal of optic canal,which is associated with complications like CSF leakage,ophthalmic artery injury,and optic nerve injury[1].Generally,the mild CSF leak is common and can heal spontaneously using conventional treatment,the severe CSF leak requires surgical repair[2].

关键词： decompression nasal traumatic

Source apportionment and specific-source-site risk of quinolone antibiotics for effluent-receiving urban rivers and groundwater in a city, China

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Environmental Sciences 2024年第10期144卷 185-198页

作者： yu Zhao yuanmeng Song Lulu Zhang bo Zhao Mengqi Lu Jiansheng Cui Wenzhong Tang State Key Laboratory of Environmental Aquatic Chemistry Research Center for Eco-Environmental SciencesChinese Academy of ScienceBeijing 100085China College of Environment Science and Engineering Hebei University of Science and TechnologyShijiazhuang 050000China University of Chinese Academy of Sciences Beijing 100049China

There is a large surface-groundwater exchange downstream ofwastewater treatment plants(WWTPs),and antibiotics upstream may influence sites downstream of ***,samples from 9 effluent-receiving urban rivers(ERURs)and 12 groundwater sites were collected in Shijiazhuang City in December 2020 and April *** ERURs,8 out of 13 target quinolone antibiotics(QNs)were detected,and the total concentration of QNs in December and April were 100.6-4,398 ng/L and 8.02–2,476 ng/L,*** groundwater,all target QNs were detected,and the total QNs concentration was 1.09–23.03 ng/L for December and 4.54–170.3 ng/L for *** distribution of QNs was dissimilar between ERURs and *** QN concentrations were weakly correlated with land use types in the *** results of a positive matrix factorization model(PMF)indicated four potential sources of QNs in both ERURs and groundwater,and WWTP effluents were the main source of *** December to April,the contribution of WWTP effluents and agricultural emissions increased,while livestock activities *** value decomposition(SVD)results showed that the spatial variation of most QNs was mainly contributed by sites downstream(7.09%-88.86%)of ***,a new method that combined the results of SVD and PMF was developed for a specific-source-site risk quotient(SRQ),and the SRQ for QNs was at high level,especially for the sites downstream of *** temporal variation,the SRQ for WWTP effluents,aquaculture,and agricultural emissions ***,in order to control the antibiotic pollution,more attention should be paid to WWTP effluents,aquaculture,and agricultural emission sources for the benefit of sites downstream of WWTPs.

关键词： Source apportionment Singular value decomposition Positive matrix factorization model Quinolone antibiotics(QNs) Specific-source-site risk quotient(SRQ) WWTP effluents

Analysis of destructive effect of Zn on carbon brick and way of Zn into carbon brick

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Iron and Steel Research International 2024年第6期31卷 1344-1354页

作者： Peng-bo Liu Shu-sen Cheng yu-qing Xue Xiao-man Cheng Zhao Liu University of Science and Technology Beijing Beijing 100083China Ministry of Ironmaking Shangdong Taishan Steel Group Co.Ltd.Taian 271000ShandongChina

The service life of a blast furnace depends largely on the degree of damage to the carbon brick in the *** brick and ramming material in the hearth of a 1780 m3 blast furnace after shutdown were sampled and *** was found that the substances in the cracks of the carbon brick near and above the taphole were ZnO and Zn_(2)SiO_(4),whereas the substances in the cracks of the carbon brick below the taphole were *** reaction of Zn with CO,SiO_(2),and Fes generates ZnO,Zn_(2)SiO_(4),and ZnS,resulting in volume expansion,which is an important reason for the cracking of carbon ***,several obvious Zn vapor flow channels were found in the ramming material,through which Zn vapor could enter the carbon brick,causing damage to the carbon *** the compactness of the ramming material is beneficial to preventing Zn vapor from entering the carbon brick through the voids in the ramming material,reducing the destructive effect of Zn on the carbon brick and further extending the service life of the blast furnace.

关键词： Zn Blast furnace Carbon brick Ramming material Crack

Visceral adipose tissue predicts severity and prognosis of acute pancreatitis in obese patients

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Hepatobiliary & Pancreatic Diseases International 2024年第5期23卷 458-462页

作者： yuan Tian Qing Huang yu-Tang Ren Xuan Jiang bo Jiang Department of Gastroenterology Beijing Tsinghua Changgung HospitalSchool of Clinical MedicineTsinghua UniversityBeijing 102218China

Acute pancreatitis is a common systemic inflammatory disease, manifested by a spectrum of severity, ranging from mild in the majority of patients to severe acute pancreatitis. Patients with severe acute pancreatitis suffer from severe local and systemic complications and organ failure, leading to a poor prognosis. The early recognition of the severe condition is important to improve prognosis. Obesity has risen in tandem with an increase in the severity of acute pancreatitis in recent years. Studies have revealed that adipose tissue, particularly visceral adipose tissue is associated with the prognosis of acute pancreatitis. This review discussed the role of visceral adipose tissue in obese patients with acute pancreatitis and explored the possible mechanism involved.

关键词： Visceral adipose tissue Obesity Acute pancreatitis

A novel method for calculating broadband electrical performance of high-speed aircraft radome under thermo-mechanical-electrical coupling

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

CHINESE JOURNAL OF AERONAUTICS 2024年第9期37卷 463-474页

作者： Ji, Jianmin Ren, Jianhua Jiang, Xunya Wang, Wei yu, Huilong Yin, Kai Chen, bo Beijing Inst Remote Sensing Equipment Beijing 100854 Peoples R China Shanghai DongJun Informat & Technol Co Ltd Shanghai 200050 Peoples R China

The electrical performance of radomes on high-speed aircraft can be influenced by the thermal and mechanical loads produced during high-speed flight, which can affect the detection distance and accuracy of the guidance system. This paper presents a new method that uses the Finite Difference Time Domain (FDTD) method to calculate the electrical performance of radomes under Thermo-Mechanical-Electrical (TME) coupling. This method can accurately characterize the effects of material dielectric temperature drift and structural deformation on the electrical performance of the radome under flight conditions, enabling high-precision full-wave calculations of the broadband electrical performance of the radome. The method initiates by utilizing a Finite Element Grid Model (FE-GM) of the radome to sequentially acquire the radome's response temperature field and structural deformation field through thermal and mechanical simulations. Subsequently, spatial mapping techniques are developed to accurately incorporate the dielectric temperature drift and structural deformation of the radome into its Yee grid Electromagnetic (EM) simulation model. A verification case was designed to test the proposed method, and the results confirmed its high computational accuracy. Additionally, the effectiveness and necessity of the method were further demonstrated by analyzing the electrical performance of a fused silica ceramic radome used on a high-speed aircraft. (c) 2024 Production and hosting by Elsevier Ltd. on behalf of Chinese Society of Aeronautics and Astronautics. This is an open access article under the CC BY-NC-ND license (http://***/ licenses/by-nc-nd/4.0/).

关键词： High-speed aircraft Radomes Thermo-Mechanical- Electrical (TME) coupling Finite Difference Time Domain (FDTD) method Spatial mapping DESIGN