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Preparation of High Activity Admixture from Steel Slag,Phosphate Slag and Limestone Powder
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作者 Ying Ji Xi Liu 《Journal of Renewable Materials》 EI 2023年第11期3977-3989,共13页
The problem of low disposal and utilization rate of bulk industrial solid waste needs to be solved.In this paper,a high-activity admixture composed of steel slag-phosphate slag-limestone powder was proposed for most o... The problem of low disposal and utilization rate of bulk industrial solid waste needs to be solved.In this paper,a high-activity admixture composed of steel slag-phosphate slag-limestone powder was proposed for most of the solid waste with low activity and a negative impact on concrete workability,combining the characteristics of each solid waste.The paper demonstrates the feasibility and explains the principle of the composite system in terms of water requirement of standard consistency,setting time,workability,and mechanical properties,combined with the composition of the phases,hydration temperature,and microscopic morphology.The results showed that the steel slag:phosphate slag:limestone=5:2:3 gave the highest activity of the composite system,over 92%.Besides,the composite system had no significant effect on water demand and setting time compared to cement,and it could significantly increase the 7 and 28 d activity of the system.The composite system delayed the exothermic hydration of the cement and reduced the exothermic heat but had no effect on the hydration products.Therefore,the research in this paper dramatically improved the solid waste dissipation in concrete,reduced the amount of cement in concrete and positively responded to the national slogan of carbon neutral and peaking. 展开更多
关键词 Steel slag phosphorus slag limestone powder high activity admixture solid waste
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To explore patients’ perceptions about motivators and barriers of adherence to highly active antiretroviral therapy among people living with HIV: A qualitative study
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作者 Sonia GULATI Hariprasath PANDURANGAN Pulin Kumar GUPTA 《Journal of Integrative Nursing》 2023年第4期256-265,共10页
Objective:For people living with HIV(PLHIV),strict adherence to highly active antiretroviral therapy(HAART)is the key to effective treatment and retention in human immunodeficiency virus(HIV)care.There are many factor... Objective:For people living with HIV(PLHIV),strict adherence to highly active antiretroviral therapy(HAART)is the key to effective treatment and retention in human immunodeficiency virus(HIV)care.There are many factors which promote or halt the antiretroviral therapy(ART)adherence practices.Therefore,the present study aimed to examine the HAART adherence levels and to explore patients’views about barriers and facilitators to HIV treatment adherence.Methods:Semi-structured interviews were conducted among 15 PLHIV at the ART clinic of Dr.Ram Manohar Lohia Hospital,New Delhi.Interviews were audio-recorded in the local Hindi language,and bilingual experts(English and Hindi)transcribed verbatim.Qualitative data were coded for themes and subthemes and analyzed using a phenomenological approach as per thematic content analysis.Results:Feeling of hopelessness,delayed ART initiation,difficult initial phase of ART,forget to take ART on time,fear of disclosure of HIV diagnosis,lack of privacy and negative social support,and impact of lockdown due to COVID-19 were revealed as significant barriers to ART adherence.At the same time,commitment to raise and educate children,ART to increase life span,maintain oneself to be physically fit and healthy,only a single pill per day,very supportive counselors and health-care professionals,and hope to give birth to a healthy child were identified as facilitators of HIV retention.Conclusion:Understanding patient’s perception about ART adherence,its motivational and barrier factors which are directly affecting ART adherence and retention of PLHIV in HIV treatment and follow-ups are of utmost importance to improve ART adherence during HIV patient care services. 展开更多
关键词 ADHERENCE barriers highly active antiretroviral therapy human immunodeficiency virus MOTIVATORS PERCEPTIONS
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Hepatitis C virus eradication in people living with human immunodeficiency virus:Where are we now?
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作者 Anna Maria Spera Pasquale Pagliano Valeria Conti 《World Journal of Hepatology》 2024年第5期661-666,共6页
Hepatitis C virus(HCV)/human immunodeficiency virus(HIV)co-infection still involves 2.3 million patients worldwide of the estimated 37.7 million living with HIV,according to World Health Organization.People living wit... Hepatitis C virus(HCV)/human immunodeficiency virus(HIV)co-infection still involves 2.3 million patients worldwide of the estimated 37.7 million living with HIV,according to World Health Organization.People living with HIV(PLWH)are six times greater affected by HCV,compared to HIV negative ones;the greater prevalence is encountered among people who inject drugs and men who have sex with men:the risk of HCV transmission through sexual contact in this setting can be increased by HIV infection.These patients experience a high rate of chronic hepatitis,which if left untreated progresses to end-stage liver disease and hepato-cellular carcinoma(HCC)HIV infection increases the risk of mother to child vertical transmission of HCV.No vaccination against both infections is still available.There is an interplay between HIV and HCV infections.Treatment of HCV is nowadays based on direct acting antivirals(DAAs),HCV treatment plays a key role in limiting the progression of liver disease and reducing the risk of HCC development in mono-and coinfected individuals,especially when used at an early stage of fibrosis,reducing liver disease mortality and morbidity.Since the sustained virological response at week 12 rates were observed in PLWH after HCV eradication,the AASLD has revised its simplified HCV treatment algorithm to also include individuals living with HIV.HCV eradication can determine dyslipidemia,since HCV promotes changes in serum lipid profiles and may influence lipid metabolism.In addition to these apparent detrimental effects on the lipid profile,the efficacy of DAA in HCV/HIV patients needs to be considered in light of its effects on glucose metabolism mediated by improvements in liver function.The aim of the present editorial is to describe the advancement in HCV treatment among PLWH. 展开更多
关键词 HEPATITIS People living with human immunodeficiency virus Direct acting antivirals highly active antiretroviral therapy CO-INFECTION
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Template-assisted synthesis of hierarchically porous Co3O4 with enhanced oxygen evolution activity
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作者 Lan Yao Hexiang Zhong +2 位作者 Chengwei Deng Xianfeng Li Huamin Zhang 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2016年第1期153-157,共5页
Oxygen evolution reaction(OER) is one of the most important reactions in the energy storage devices such as metal–air batteries and unitized regenerative fuel cells(URFCs). However, the kinetically sluggishness o... Oxygen evolution reaction(OER) is one of the most important reactions in the energy storage devices such as metal–air batteries and unitized regenerative fuel cells(URFCs). However, the kinetically sluggishness of OER and the high prices as well as the scarcity of the most active precious metal electrocatalysts are the major bottleneck in these devices. Developing low-cost non-precious metal catalysts with high activity and stability for OER is highly desirable. A facile, in situ template method combining the dodecyl benzene sulfuric acid sodium(SDBS) assisted hydrothermal process with subsequent high-temperature treatment was developed to prepare porous Co3O4 with improved surface area and hierarchical porous structure as precious catalysts alternative for oxygen evolution reaction(OER). Due to the unique structure, the as-prepared catalyst shows higher electrocatalytic activity than Co3O4 prepared by traditional thermal-decomposition method(noted as Co3O4-T) and commercial IrO2 catalyst for OER in 0.1M KOH aqueous solution. Moreover, it displays improved stability than Co3O4-T. The results demonstrate a highly efficient, scalable, and low cost method for developing highly active and stable OER electrocatalysts in alkaline solutions. 展开更多
关键词 Oxygen evolution reaction Co3O4 Non-precious metal catalysts high activity high stability
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The Effect Evaluation of Highly Active Antiretroviral Therapy to Patients with AIDS in Hubei Province of China 被引量:5
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作者 李雪华 许奕华 +2 位作者 聂绍发 向浩 王重建 《Journal of Huazhong University of Science and Technology(Medical Sciences)》 SCIE CAS 2009年第5期580-584,共5页
The effects of highly active antiretroviral therapy (HAART) to patients with AIDS in Hubei province of China were investigated in order to provide scientific evidence to reinforce the management of HAART. Self-made ... The effects of highly active antiretroviral therapy (HAART) to patients with AIDS in Hubei province of China were investigated in order to provide scientific evidence to reinforce the management of HAART. Self-made questionnaires and descriptive method of epidemiology were used to collect and describe the changes of clinical symptoms, HIV RIgA concentration, and immune function of patients with AIDS. After HAART, the effective rate of fever, cough, diarrhea, lymphadenectasis, weight loss, tetter, debility and fimgous infection was 92.4%, 90.85%, 92.91%, 90.73%, 93.69%, 89.04%, 92.34%, and 83.1%, respectively. Of 117 patients with detected HIV RNA concentration, 41.03% had declined over 0.5 log, and 52.99% less than 0.5 log. CD4^+T cell count was obviously increased: the average number after HAART for 3 or 6 months was 237μL (26-755μL) and 239μL (17-833μL), respectively HAART can improve AIDS patients' clinical symptoms, reduce HIV RNA concentration, and maintain immune function. It is very important for the effectiveness of HAART to raise clinical adherence of pa- tients with AIDS and have a persistent surveillance. 展开更多
关键词 AIDS highly active antiretroviral therapy clinical adherence
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New Activated Carbon with High Thermal Conductivity and Its Microwave Regeneration Performance 被引量:4
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作者 谷雪贤 SU Zhanjun 奚红霞 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2016年第2期328-333,共6页
Using a walnut shellas a carbon source and ZnCl_2 as an activating agent,we resolved the temperature gradient problems of activated carbon in the microwave desorption process.An appropriate amount of silicon carbide w... Using a walnut shellas a carbon source and ZnCl_2 as an activating agent,we resolved the temperature gradient problems of activated carbon in the microwave desorption process.An appropriate amount of silicon carbide was added to prepare the composite activated carbon with high thermalconductivity while developing VOC adsorption-microwave regeneration technology.The experimentalresults show that the coefficient of thermalconductivity of SiC-AC is three times as much as those of AC and SY-6.When microwave power was 480 W in its microwave desorption,the temperature of the bed thermaldesorption was 10 ℃ to 30 ℃ below that of normalactivated carbon prepared in our laboratory.The toluene desorption activation energy was 16.05 k J·mol^(-1),which was 15% less than the desorption activation energy of commercialactivated carbon.This study testified that the process could maintain its high adsorption and regeneration desorption performances. 展开更多
关键词 activated carbon with high thermal conductivity activation energy for desorption VOCs microwave radiation
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Numerical Simulation of the Relationship between the Anomaly of Subtropical High over East Asia and the Convective Activities in the Western Tropical Pacific 被引量:37
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作者 黄荣辉 卢里 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 1989年第2期202-214,共13页
In this paper, a close relationship between the intraseasonal variation of subtropical high over East Asia and the convective activities around the South China Sea and the Philippines is analysed from OLR data.This re... In this paper, a close relationship between the intraseasonal variation of subtropical high over East Asia and the convective activities around the South China Sea and the Philippines is analysed from OLR data.This relationship is studied by using the theory of wave propagating in a slowly varying medium and by using a quasi-geoslrophic, linear, spherical model and the IAP-GCM, respectively. The results show that when the SST is warming around the western tropical Pacific or the Philippines, the convective activities are intensified around the Philippines. As a consequence, the subtropical high will be intensified over East Asia. The computed results also show that when the anomaly of convective activities are caused around the Philippines, a teleconnection pattern of circulation anomalies will be caused over South Asia, East Asia and North America. 展开更多
关键词 OVER Numerical Simulation of the Relationship between the Anomaly of Subtropical high over East Asia and the Convective Activities in the Western Tropical Pacific Asia
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Cytomegalovirus retinitis in the highly active anti-retroviral therapy era 被引量:1
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作者 Ifeoma N.Ude Steven Yeh Jessica G.Shantha 《Annals of Eye Science》 2022年第1期42-50,共9页
Cytomegalovirus(CMV)retinitis is an opportunistic infection that has traditionally affected those who have HIV/AIDS or immunosuppressed individuals.CMV retinitis previously infected one-third of AIDS patients in the p... Cytomegalovirus(CMV)retinitis is an opportunistic infection that has traditionally affected those who have HIV/AIDS or immunosuppressed individuals.CMV retinitis previously infected one-third of AIDS patients in the pre-highly active antiretroviral therapy(HAART)era,but since HAART,Western countries have seen an 80%decrease in the incidence of the disease.More recently,CMV retinitis has been reported in patients who are immunosuppressed,often due to chemotherapy or immunomodulatory medications.The diagnosis of CMV retinitis is often suspected based on clinical findings,with polymerase chain reaction for confirmation of CMV,especially in atypical cases.Highly active antiretroviral therapy and anti-CMV medications(systemic or local)remain the mainstay of treatment.However,for those who are not responsive to HAART,CMV retinitis remains a challenge,and can still lead to significant vision loss.Moreover,a regimen of anti-CMV medications can sometimes lead to viral resistance or organ toxicity.Complications such as immune recovery retinitis and rhegmatogenous retinal detachments continue to threaten the vision of patients who develop CMV retinitis.These complications can arise following initiation of treatment or if patients show disease progression.Proper vision screening for CMV retinitis in immunosuppressed patients at-risk is necessary for early detection and treatment. 展开更多
关键词 Cytomegalovirus(CMV) RETINITIS highly active antiretroviral therapy(HAART)
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Ni/Mo_2 N as a Highly Active Hydrodenitrogenation Catalyst
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作者 Wen Yu ZHANG Xin Ping WANG +1 位作者 Heng Fang JIN Qin XIN (State key Laboratory of Catalysis,Dalian Institute of Chemical Physiscs,Chinese Academy Of Sciences,Dalian 116023)(Inner Mongolia Polytechnic Universal,Huhhot 010062) 《Chinese Chemical Letters》 SCIE CAS CSCD 1996年第9期849-852,共4页
The catalysts were prepared by the temperature programmed reaction (TPR) of MoO3 with NH3 at various temperatures in the range of 573K~973K, and their hydrodenitrogenation (HDN) activities were tested in situ.It is s... The catalysts were prepared by the temperature programmed reaction (TPR) of MoO3 with NH3 at various temperatures in the range of 573K~973K, and their hydrodenitrogenation (HDN) activities were tested in situ.It is shown that molybdenum nitrid(Mo2N) was formed above 923K and its intermediate MoO2 formed at about 573~623K under the rapid (5K/min.) TPR conditions.Mo2N is the most active species for pyridine HDN among MoO3,MoO2,MoS2,and Mo2N. Moreover,it can be promoted by adding Ni component.It is shown that the Ni/Mo2N catalyst prepared by adding some NiO into the precursor MoO3 has a steady HDN activity Which is far higher than that of the commercial sulfided NiMo/Al2O3(HR346) catalyst. 展开更多
关键词 MO Ni/Mo2 N as a highly Active Hydrodenitrogenation Catalyst
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Preparation and Properties of Ultra-fine Chromium Carbonization of High Performance Mechanical Activation
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作者 田磊 CHEN Lijie +3 位作者 张廷安 Lü Guozhi LIU Yan ZHANG Ying 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2018年第1期56-63,共8页
The preparation of hydroxyl chromium oxide by hydrogen reduction of disodium chromate and particulate hydroxyl mechanical activation features were studied. Then with self-made hydroxyl chromium as the raw material, a ... The preparation of hydroxyl chromium oxide by hydrogen reduction of disodium chromate and particulate hydroxyl mechanical activation features were studied. Then with self-made hydroxyl chromium as the raw material, a direct reduction and carburization process was used to prepare ultra-fine chromium carbonization. Through SEM and XRD, the high performance mechanical activation, key coefficients, microstructure, hardness and wear-resisting property were investigated. The results reveal that suitable mechanical activation and carbon reducing carbonization temperature, carbonization time, carbon content are beneficial to obtaining ultra-fine chromium carbonization. Typically, when the time of high performance grinding is 5 min, the carbon reducing temperature is 1100 ℃, the carbon reducing time is 1h, the carbon content is 28%, and finally the particle size of chromium carbide powder is 1 μm. Under this condition of preparation of ultra-fine chromium carbide, both the hardness and wear resistance are better than those in the industrialization of chromium carbide coating. 展开更多
关键词 direct reduction and carburization method hydroxyl chromium oxide high performance mechanical activation ultra-fine chromium carbide MORPHOLOGY
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Autoimmune hepatitis in a patient infected by HIV-1 and under highly active antiretroviral treatment:Case report and literature review
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作者 Marta Casal Moura Edite Pereira +4 位作者 Vítor Braz Catarina Eloy Joanne Lopes Fátima Carneiro José Paulo Araújo 《World Journal of Immunology》 2014年第3期194-198,共5页
Liver disease has recently been described as an important cause of morbidity and mortality in patients infected with human immunodeficiency virus(HIV). Liver test changes are useful surrogates of the burden of liver d... Liver disease has recently been described as an important cause of morbidity and mortality in patients infected with human immunodeficiency virus(HIV). Liver test changes are useful surrogates of the burden of liver disease. Previous studies have shown that transaminase elevations are frequent among these patients. The cause of those changes is harder to establish in HIV-patients. We present a 61-year-old caucasian male,diagnosed with HIV type 1 infection since 1998,under highly active antiretroviral treatment(HAART),with virological suppression and immunological recovery. He presented in a follow-up laboratory workup high values of transaminases,arthralgia at the hip joints and hepatomegaly. Liver function tests were normal. The antibodies to hepatitis viruses were negative. However,autoimmune study and liver biopsy were compatible with autoimmune hepatitis(AIH). The AIH is a rare di-agnosis in HIV-infected patients perhaps because the elevation of transaminases and changes in liver function tests are often associated to HAART or to other possible liver diseases,namely viral hepatitis and non-alcoholic steatohepatitis. The diagnosis may be underestimated. There are no specific recommendations available for the treatment of HIV-associated AIH although the immunosupression with slower tapering seems the most reasonable approach. 展开更多
关键词 Autoimmune hepatitis Human immunode-fciency virus type 1 highly active antiretroviral treat-ment Liver tests Liver biopsy
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Highly Active Anhydrous Potassium Fluoride
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《China's Foreign Trade》 1995年第2期22-22,共1页
Highly active anhydrous potassium fluoride has many uses. Its good performance is demonstrated in high activity, high recovery, low consumption and the low emission of accessory substances during the process of organi... Highly active anhydrous potassium fluoride has many uses. Its good performance is demonstrated in high activity, high recovery, low consumption and the low emission of accessory substances during the process of organic fluorination. Moreover. there is no need to use an expensive intertransferable catalyst in the process of fluorination. Under the same conditions and within the same time limit, the fluorination rate of the product is 97% while that of ordinary anhydrous potassium fluoride is 58%. The product, developed recently by the Shenyang Chemical Research Institute, can remain in a state of superfine powder for a long time in air 展开更多
关键词 high highly Active Anhydrous Potassium Fluoride
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Thermal Activation Analyses of Dynamic FractureToughness of High Strength Low Alloy Steels
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作者 Cunjian LI and Shaohua LI Welding Research Department, Central Iron & Steel Research Institute, Beijing 100081, China Yuqing DENG State Administration of Metallurgical Industry, Beijing 100711, China 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 2001年第2期215-218,共4页
A formula is derived for determining the influence of temperature and loading rate on dynamic fracture toughness of a high strength low alloy steel (HQ785C) from thermal activation analysis of the experimental results... A formula is derived for determining the influence of temperature and loading rate on dynamic fracture toughness of a high strength low alloy steel (HQ785C) from thermal activation analysis of the experimental results of three-point bend specimens as well as introducing an Arrhenius formula. It is shown that the results obtained by the given formula are in good agreement with the experimental ones in the thermal activation region. The present method is also valuable to describe the relationship between dynamic fracture toughness and temperature and loading rate of other high strength low alloy steels. 展开更多
关键词 TEST GB Thermal Activation Analyses of Dynamic FractureToughness of high Strength Low Alloy Steels
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OPTICALLY ACTIVE AMINO ACIDS WITH HIGHLY BRANCHED SIDE CHAIN (I) SYNTHESIS OF D- AND L- 2-AMINO-5,5-DIMETHYLHEXANOIC ACID AND 2-AMINO-6,6-DIMETHYLHEPTANOIC ACID
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《Chinese Chemical Letters》 SCIE CAS CSCD 1992年第4期237-238,共2页
The title compounds were prepared by the enzymatic resolution of the corresponding N-acetylated DL-amino acids methyl esters, which were obtained from t-butyl chloride via an 8-step synthesis.
关键词 AMINO-5 5-DIMETHYLHEXANOIC ACID AND 2-AMINO-6 6-DIMETHYLHEPTANOIC ACID AND L OPTICALLY ACTIVE AMINO ACIDS WITH highLY BRANCHED SIDE CHAIN SYNTHESIS OF D
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High Efficiency and Stable Organic Light-Emitting Diodes Based on Thermally Activated Delayed Fluorescence Emitter
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作者 吕孝鹏 王会 +7 位作者 孟令强 魏晓芳 陈永振 孔祥彬 刘建君 唐建新 汪鹏飞 王鹰 《Chinese Physics Letters》 SCIE CAS CSCD 2016年第8期139-142,共4页
High efficiency, stable organic light-emitting diodes (OLEDs) based on 2-pheyl-4'-carbazole-9-H-Thioxanthen-9- one-10, 10-dioxide (TXO-PhCz) with different doping concentration are constructed. The stability of t... High efficiency, stable organic light-emitting diodes (OLEDs) based on 2-pheyl-4'-carbazole-9-H-Thioxanthen-9- one-10, 10-dioxide (TXO-PhCz) with different doping concentration are constructed. The stability of the encap- sulated devices are investigated in detail. The devices with the 10 wt% doped TXO-PhCz emitter layer (EML) show the best performance with a current efficiency of 52.1 cd/A, a power efficiency of 32.71re^W, and an external quantum efficiency (EQE) of 17.7%. The devices based on the lOwt%-doped TXO-PhCz EML show the best operational stability with a half-life time (LTSO) of 8Oh, which is 8 h longer than that of the reference devices based on fac-tris(2-phenylpyridinato)iridium( Ⅲ) (Ir(ppy)a). These indicate excellent stability of TXO-PhCz for redox and oxidation processes under electrical excitation and TXO-PhCz can be potentially used as the emitters for OLEDs with high efficiency and excellent stability. The high-performance device based on TXO-PhCz with high stability can be further improved by the optimization of the encapsulation technology and the development of a new host for TXO-PhCz. 展开更多
关键词 OLEDs in of high Efficiency and Stable Organic Light-Emitting Diodes Based on Thermally Activated Delayed Fluorescence Emitter EML on for
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Ultrathin organic polymer with p-πconjugated structure for simultaneous photocatalytic disulfide bond generation and CO_(2)reduction
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作者 Linquan Hou Zhunyun Tang +6 位作者 Guojiang Mao Shiheng Yin Bei Long Tao Ouyang Guo-Jun Deng Atif Ali Ting Song 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2023年第1期639-647,I0016,共10页
Combining photocatalytic organic reactions with CO_(2)reduction is an efficient solar energy utilization mode,but it is still limited by the organic species that can be matched and the low conversion.Herein,ultrathin ... Combining photocatalytic organic reactions with CO_(2)reduction is an efficient solar energy utilization mode,but it is still limited by the organic species that can be matched and the low conversion.Herein,ultrathin organic polymer with p-πconjugated structure(TPP)was rationally designed and prepared,and showed a high yield of CO(15.2 mmol g^(-1))and conversion of SAS coupled products(100%),far exceeding the organic polymer with P=O structure.The enhanced photoredox activity of TPP is ascribed to the orbital interaction between the p-orbital on phosphorus and theπ-orbitals of aromatic,which can accelerate the photoinduced charge carrier separation and improve the CO_(2)adsorption capacity.TPP can also be used for the dehydrocoupling of various benzyl mercaptans to the corresponding SAS bond products.This work provides a new concept for the efficient synthesis of disulfide bonds combined with CO_(2)reduction in a photoreaction system. 展开更多
关键词 Photocatalytic coupled reaction Disulfide bond CO_(2)reduction high activity Organic polymer
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Homoepitaxial growth of (100) Si-doped β-Ga_(2)O_(3) films via MOCVD
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作者 Wenbo Tang Xueli Han +11 位作者 Xiaodong Zhang Botong Li Yongjian Ma Li Zhang Tiwei Chen Xin Zhou Chunxu Bian Yu Hu Duanyang Chen Hongji Qi Zhongming Zeng Baoshun Zhang 《Journal of Semiconductors》 EI CAS CSCD 2023年第6期39-45,共7页
Homoepitaxial growth of Si-doped β-Ga_(2)O_(3) films on semi-insulating(100) β-Ga_(2)O_(3) substrates by metalorganic chemical vapor deposition(MOCVD) is studied in this work. By appropriately optimizing the growth ... Homoepitaxial growth of Si-doped β-Ga_(2)O_(3) films on semi-insulating(100) β-Ga_(2)O_(3) substrates by metalorganic chemical vapor deposition(MOCVD) is studied in this work. By appropriately optimizing the growth conditions, an increasing diffusion length of Ga adatoms is realized, suppressing 3D island growth patterns prevalent in(100) β-Ga_(2)O_(3) films and optimizing the surface morphology with [010] oriented stripe features. The slightly Si-doped β-Ga_(2)O_(3) film shows smooth and flat surface morphology with a root-mean-square roughness of 1.3 nm. Rocking curves of the(400) diffraction peak also demonstrate the high crystal quality of the Si-doped films. According to the capacitance–voltage characteristics, the effective net doping concentrations of the films are 5.41 × 10~(15) – 1.74 × 10~(20) cm~(-3). Hall measurements demonstrate a high electron mobility value of 51cm~2/(V·s), corresponding to a carrier concentration of 7.19 × 10~(18) cm~(-3) and a high activation efficiency of up to 61.5%. Transmission line model(TLM) measurement shows excellent Ohmic contacts and a low specific contact resistance of 1.29 × 10~(-4) Ω·cm~2 for the Si-doped film, which is comparable to the Si-implanted film with a concentration of 5.0 × 10~(19) cm~(-3), confirming the effective Si doing in the MOCVD epitaxy. 展开更多
关键词 homoepitaxial growth MOCVD Si-doping films high activation efficiency Ohmic contacts
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Nano-flower spherical SnS2 combined with a special lithium storage mechanism as a multifunctional separator for lithium-sulfur batteries contributes to ultra-high initial discharge specific capacity
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作者 LIU HuaZhong XIONG YaPing +5 位作者 HUANG MouZhi CHEN ZongMin YANG Xiao ZHANG Ze YANG ZhenYu CAI JianXin 《Science China(Technological Sciences)》 SCIE EI CAS CSCD 2024年第2期509-519,共11页
The critical factors that limit the electrochemical performance of lithium-sulfur(Li-S)batteries are mainly the“shuttle effect”of polysulfides and the slow redox reaction between lithium polysulfides(LiPSs).Herein,a... The critical factors that limit the electrochemical performance of lithium-sulfur(Li-S)batteries are mainly the“shuttle effect”of polysulfides and the slow redox reaction between lithium polysulfides(LiPSs).Herein,a nano-sphere-type material selfassembled from tin disulfide nanosheets is designed and applied to the Li-S cell separator in this work.The SnS_(2)@PP modified separator not only acts as a dual restriction for LiPSs by chemisorption and physical barrier.At the same time,it improves the catalytic activity of the redox reaction between LiPSs.The SnS_(2)has extremely high electrochemical activity.There,a portion of the lithium ions can be inserted into SnS_(2)to form Li_(x)SnS_(2)and contribute to the capacity during the first discharge of the battery.In addition,Li_(x)SnS_(2)possesses a high degree of stability,and it does not undergo further de-alloying reactions even at the high potential of the Li-S cell.The benefit is that the steady-state Li_(x)SnS_(2)acts as a lithium-containing substance.It can form special Li^(+)channels on the surface of the separator,thus greatly improving the efficiency of Li+transport.The results showed that the SnS_(2)@PP-based cell exhibited extremely high initial discharge specific capacity(1477 m Ah g^(-1)at 0.1 C)and excellent rate performance(631 m Ah g^(-1)at 5 C).Even after 1000 cycles at 2 C,the cell exhibited a low decay rate of 0.06%per cycle on average.In addition,the superior electrochemical performance was obtained even with a high sulfur loading of 5.1 mg cm^(-2)and low electrolyte of E/S=8μL mg^(-1). 展开更多
关键词 Li-S batteries modified separators POLYSULFIDES catalytic conversion high electrochemical activity
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Highly exposed Cu active sites as efficient peroxidase mimics for colorimetric analysis
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作者 Hengya Wei Shushu Chu +2 位作者 Fangning Liu Shengzhen Li Yizhong Lu 《ChemPhysMater》 2024年第2期204-211,共8页
Nanozymes are nanomaterials with intrinsic enzyme-mimic activity,but their large-scale application is generally limited by their low catalytic activity.Herein,we demonstrated that highly exposed Cu active sites on two... Nanozymes are nanomaterials with intrinsic enzyme-mimic activity,but their large-scale application is generally limited by their low catalytic activity.Herein,we demonstrated that highly exposed Cu active sites on two-dimensional(2D)nitrogen-doped carbon(Cu_(x)/NC)can serve as efficient peroxidase-like(POD)catalysts with high atomic utilization.Specially,the uniformly distributed Cu active sites could react with H_(2)O_(2)to produce singlet oxygen(^(1)O_(2))under acidic conditions,which can efficiently oxidizes colorless 3,3',5,5'-tetramethylbenzidine(TMB)to blue oxidized TMB(oxTMB).Among various Cu_(x)/NC nanozymes studied,the Cuo.14/NC exhibited smaller maximum catalytic velocities(V_(max))and Menten constant(K_(m))for TMB and H_(2)O_(2).Benefiting from the highly active peroxidase-like activity,the Cu_(0.14)/NC nanozyme could be successfully applied for the hydroquinone(HQ)and ascorbic acid(AA)detection applications through the inhibitory effect of HQ and AA.More interestingly,α-glucosidase(α-Glu)detection sensing platform could be constructed based on HQ as a signal transmitter,with the detection range ranging from O to 12 U/L and the minimum detection limit being 0.68 U/L.This work provides not only an idea for the rational design of highly exposed Cu active sites but also fabricate an effective detection sensing platform forHQ,AA,andα-Glu detection. 展开更多
关键词 Nanozyme highly exposed active sites Peroxidase-like Α-GLUCOSIDASE Sensing
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Transition metaldoping effect and high catalytic activity of CeO_(2)-TiO_(2) for chlorinated VOCs degradation 被引量:1
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作者 Yijun Shi Xiaolin Guo +1 位作者 Zhinan Shi Renxian Zhou 《Journal of Rare Earths》 SCIE EI CAS CSCD 2022年第5期745-752,I0003,共9页
A series of transition metals(Fe,Co,Ni,Cu,Cr and Mn)-doped CeO_(2)-TiO_(2) catalysts were prepared by the sol-gel method and applied for the catalytic removal of 1,2-dichloroethane(DCE) as a model for chlorinated VOCs... A series of transition metals(Fe,Co,Ni,Cu,Cr and Mn)-doped CeO_(2)-TiO_(2) catalysts were prepared by the sol-gel method and applied for the catalytic removal of 1,2-dichloroethane(DCE) as a model for chlorinated VOCs(CVOCs).The various characterization methods including X-ray diffraction(XRD),N_(2) adsorption-desorption,UV-Raman,NH_(3) temperature-programmed desorption(NH_(3)-TPD) and H_(2) temperature-programmed reduction(H_(2)-TPR) were utilized to investigate the physicochemical properties of the catalysts.The results show that doping Fe,Co,Ni or Mn can obviously promote the activity of CeO_(2)-TiO_(2) mixed oxides for DCE degradation,which is related to their improved texture properties,acid sites(especially for strong acidity) and low-temperature reducibility.Particularly,CeTi-Fe doped with moderate Fe exhibits excellent activity for 1,2-dichloroethane(DCE) degradation,giving a T_(90%) value as low as 250℃.More importantly,only trace chlorinated byproducts were produced during the low-temperature degradation of various CVOCs(dichloromethane(DCM),trichloroethylene(TCE) and chlorobenzene(CB)) over CeTi-Fe1/9 catalyst with high durability. 展开更多
关键词 Transition metals doping CeO_(2)-TiO_(2)mixed oxides CVOCs degradation high activity Excellent durability Rare earths
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