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Thermogravimetric characteristics of corn straw and bituminous coal copyrolysis based the ilmenite oxygen carriers
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作者 Pengxing Yuan Xiude Hu +2 位作者 Jingjing Ma Tuo Guo Qingjie Guo 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2024年第4期8-15,共8页
Herein,the co-pyrolysis reaction characteristics of corn straw(CS)and bituminous coal in the presence of ilmenite oxygen carriers(OCs)are investigated via thermogravimetry coupled with mass spectrometry.The results re... Herein,the co-pyrolysis reaction characteristics of corn straw(CS)and bituminous coal in the presence of ilmenite oxygen carriers(OCs)are investigated via thermogravimetry coupled with mass spectrometry.The results reveal that the participation of OCs weakens the devolatilization intensity of co-pyrolysis.When the CS blending ratio is<50%,the mixed fuel exhibits positive synergistic effects.The fitting results according to the Coats-Redfern integral method show that the solid-solid interaction between OCs and coke changes the reaction kinetics,enhancing the co-pyrolysis reactivity at the high-temperature zone(750-950C).The synergistic effect is most prominent at a 30%CS blending ratio,with copyrolysis activation energy in the range of 26.35-40.57 kJ·mol^(-1). 展开更多
关键词 Oxygen carrier CO-PYROLYSIS BIOMASS COAL
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Clinical Analysis and Mental Health Survey of Hemophilia Carriers:a Cross-sectional Study
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作者 Wen WANG Li-juan JIANG +4 位作者 Dong-yan CUI Ai ZHANG Xiong WANG Ai-guo LIU Qun HU 《Current Medical Science》 SCIE CAS 2024年第2期435-440,共6页
Objective:Hemophilia carriers(HCs),who are heterozygous for mutations in the clotting factor VIII/clotting factor IX gene(F8 or F9),may have a wide range of clotting factor levels,from very low,similar to afflicted ma... Objective:Hemophilia carriers(HCs),who are heterozygous for mutations in the clotting factor VIII/clotting factor IX gene(F8 or F9),may have a wide range of clotting factor levels,from very low,similar to afflicted males,to the upper limit of normal,and may experience mental health issues.The purpose of this study was to provide genetic information on mothers of hemophilia patients and to understand the clotting factor activity and phenotype of HCs.Additionally,we aimed to investigate the mental health status of HCs in China.Methods:A total of 127 hemophilia mothers,including 93 hemophilia A(HA)mothers and 34 hemophilia B(HB)mothers,were enrolled in this study.Long distance PCR,multiplex PCR,and Sanger sequencing were used to analyze mutations in F8 or F9.Coagulation factor activity was detected by a one-stage clotting assay.The Symptom Checklist 90(SCL-90,China/Mandarin version)was given to HCs at the same time to assess their mental health.Results:A total of 90.6%of hemophilia mothers were diagnosed genetically as carriers,with inversion in intron 22 and missense mutations being the most common mutation types in HA and HB carriers,respectively.The median clotting factor level in carriers was 0.74 IU/mL(ranging from 0.09 to 1.74 IU/mL)compared with 1.49 IU/mL(ranging from 0.93 to 1.89 IU/mL)in noncarriers,of which 14.3%of HCs had clotting factor levels of 0.40 IU/mL or below.A total of 53.8%(7/13)of HA carriers with low clotting factor levels(less than 0.50 IU/mL)had a history of bleeding,while none of the HB carriers displayed a bleeding phenotype.The total mean score and the global severity index of the SCL-90 for surveyed HCs were 171.00(±60.37)and 1.78(±0.59),respectively.A total of 67.7%of the respondents had psychological symptoms,with obsessive-compulsive disorder being the most prevalent and severe.The pooled estimates of all nine factors were significantly higher than those in the general population(P<0.05).Conclusions:The detection rate of gene mutations in hemophilia mothers was 90.6%,with a median clotting factor level of 0.74 IU/mL,and 14.3%of HCs had a clotting factor level of 0.40 IU/mL or below.A history of bleeding was present in 41.2%of HCs with low clotting factor levels(less than 0.50 IU/mL).Additionally,given the fragile mental health status of HCs in China,it is critical to develop efficient strategies to improve psychological well-being. 展开更多
关键词 hemophilia A hemophilia B MUTATION carrier mental health
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Advances in the development of amorphous solid dispersions:The role of polymeric carriers 被引量:1
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作者 Jie Zhang Minshan Guo +1 位作者 Minqian Luo Ting Cai 《Asian Journal of Pharmaceutical Sciences》 SCIE CAS 2023年第4期45-79,共35页
Amorphous solid dispersion(ASD)is one of the most effective approaches for delivering poorly soluble drugs.In ASDs,polymeric materials serve as the carriers in which the drugs are dispersed at the molecular level.To p... Amorphous solid dispersion(ASD)is one of the most effective approaches for delivering poorly soluble drugs.In ASDs,polymeric materials serve as the carriers in which the drugs are dispersed at the molecular level.To prepare the solid dispersions,there are many polymers with various physicochemical and thermochemical characteristics available for use in ASD formulations.Polymer selection is of great importance because it influences the stability,solubility and dissolution rates,manufacturing process,and bioavailability of the ASD.This review article provides a comprehensive overview of ASDs from the perspectives of physicochemical characteristics of polymers,formulation designs and preparation methods.Furthermore,considerations of safety and regulatory requirements along with the studies recommended for characterizing and evaluating polymeric carriers are briefly discussed. 展开更多
关键词 Amorphous solid dispersions Polymeric carriers STABILITY DISSOLUTION Bioavailbility Molecular interactions
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Advances in Research on Cellulose-based Drug Carriers 被引量:1
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作者 Miaoxiu Yang Yanrou Zhang +3 位作者 Zhenhua Liu Lina Liu Xin Wang Liwei Qian 《Paper And Biomaterials》 CAS 2023年第4期55-68,共14页
Traditional drug delivery methods are prone to large fluctuations in drug concentration and require multiple frequent doses.As a green material with excellent properties,cellulose has been widely used as a drug carrie... Traditional drug delivery methods are prone to large fluctuations in drug concentration and require multiple frequent doses.As a green material with excellent properties,cellulose has been widely used as a drug carrier for the development and preparation of drug controlled-release system.Based on the mechanisms of slow drug release,such as dissolution-diffusion release,degradation release,and nanochannel-controlled release,the preparation methods of cellulose-based drug carriers are introduced in this paper.The applications of cellulose-based drug carriers in the fields of antitumor therapy,antibacterial therapy,chronic disease treatment,and viral disease treatment are summarized with the aim of providing a useful reference for research on cellulose-based drug carriers. 展开更多
关键词 CELLULOSE drug carrier drug controlled-release
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The Extended Hybrid Carrier-Based Multiple Access Technology for High Mobility Scenarios 被引量:1
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作者 Ge Song Xiaojie Fang Xuejun Sha 《China Communications》 SCIE CSCD 2024年第1期53-68,共16页
The hybrid carrier(HC)system rooted in the carrier fusion concept is gradually garnering attention.In this paper,we study the extended hybrid carrier(EHC)multiple access scheme to ensure reliable wireless communicatio... The hybrid carrier(HC)system rooted in the carrier fusion concept is gradually garnering attention.In this paper,we study the extended hybrid carrier(EHC)multiple access scheme to ensure reliable wireless communication.By employing the EHC modulation,a power layered multiplexing framework is realized,which exhibits enhanced interference suppression capability owing to the more uniform energy distribution design.The implementation method and advantage mechanism are explicated respectively for the uplink and downlink,and the performance analysis under varying channel conditions is provided.In addition,considering the connectivity demand,we explore the non-orthogonal multiple access(NOMA)method of the EHC system and develop the EHC sparse code multiple access scheme.The proposed scheme melds the energy spread superiority of EHC with the access capacity of NOMA,facilitating superior support for massive connectivity in high mobility environments.Simulation results have verified the feasibility and advantages of the proposed scheme.Compared with existing HC multiple access schemes,the proposed scheme exhibits robust bit error rate performance and can better guarantee multiple access performance in complex scenarios of nextgeneration communications. 展开更多
关键词 extended hybrid carrier system high mo-Received:Jun.09 2023 Revised:Nov.20 2023 Editor:Yuanwei Liu bility communications multiple access
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Regulation of the quantum barrier and carrier transport toward high-efficiency quasi-2D Dion-Jacobson tin perovskite solar cells
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作者 Huanhuan Yao Chang Shi +5 位作者 Tai Wu Shurong Wang Mingyu Yin Liming Ding Yong Hua Feng Hao 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第8期200-207,I0005,共9页
Quasi-2D Dion-Jacobson(DJ)tin halide perovskite has attracted much attention due to its elimination of Van der Waals gap and enhanced environmental stability.However,the bulky organic spacers usually form a natural qu... Quasi-2D Dion-Jacobson(DJ)tin halide perovskite has attracted much attention due to its elimination of Van der Waals gap and enhanced environmental stability.However,the bulky organic spacers usually form a natural quantum well structure,which brings a large quantum barrier and poor film quality,further limiting the carrier transport and device performance.Here,we designed three organic spacers with different chain lengths(ethylenediamine(EDA),1,3-propanediamine(PDA),and 1,4-butanediamine(BDA))to investigate the quantum barrier dependence.Theoretical and experimental characterizations indicate that EDA with short chain can reduce the lattice distortion and dielectric confinement effect,which is beneficial to the effective dissociation of excitons and the inhibition of trap-free non-radiative relaxation.In addition,EDA cation shows strong interaction with the inorganic octahedron,realizing large aggregates in precursor solution and high-quality films with improved structural stability.Furthermore,femtosecond transient absorption proves that EDA cations can also weaken the formation of small n-phases with large quantum barrier to achieve effective carrier transport between different nphases.Finally,the quasi-2D DJ(EDA)FA_(9)Sn_(10)I_(31)solar cells achieves a 7.07%power conversion efficiency with good environment stability.Therefore,this work sheds light on the regulation of the quantum barrier and carrier transport through the chain length of organic spacer for qua si-2D DJ lead-free perovskites. 展开更多
关键词 Chain lengths Organic spacers Quantum well carrier transport Lattice distortion
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Optimizing the sulfur-resistance and activity of perovskite oxygen carrier for chemical looping dry reforming of methane
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作者 Yuelun Li Dong Tian +6 位作者 Lei jiang Huicong Zuo LiNan Huang Mingyi Chen Jianchun Zuo Hua Wang Kongzhai Li 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第9期259-271,共13页
Perovskite oxides has been attracted much attention as high-performance oxygen carriers for chemical looping reforming of methane,but they are easily inactivated by the presence of trace H_(2)S.Here,we propose to modu... Perovskite oxides has been attracted much attention as high-performance oxygen carriers for chemical looping reforming of methane,but they are easily inactivated by the presence of trace H_(2)S.Here,we propose to modulate both the activity and resistance to sulfur poisoning by dual substitution of Mo and Ni ions with the Fe-sites of LaFeO_(3)perovskite.It is found that partial substitution of Ni for Fe substantially improves the activity of LaFeO_(3)perovskite,while Ni particles prefer to grow and react with H_(2)S during the long-term successive redox process,resulting in the deactivation of oxygen carriers.With the presence of Mo in LaNi_(0.05)Fe_(0.95)O_(3−σ)perovskite,H_(2)S preferentially reacts with Mo to generate MoS_(2),and then the CO_(2)oxidation can regenerate Mo via removing sulfur.In addition,Mo can inhibit the accumulation and growth of Ni,which helps to improve the redox stability of oxygen carriers.The LaNi_(0.05)Mo_(0.07)Fe_(0.88)O_(3−σ)oxygen carrier exhibits stable and excellent performance,with the CH_(4)conversion higher than 90%during the 50 redox cycles in the presence of 50 ppm H_(2)S at 800℃.This work highlights a synergistic effect in the perovskite oxides induced by dual substitution of different cations for the development of high-performance oxygen carriers with excellent sulfur tolerance. 展开更多
关键词 Perovskite oxygen carriers Chemical looping reforming Sulfur-resistance Dual substitution SYNGAS
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Vertical plane depth-resolved surface potential and carrier separation characteristics in flexible CZTSSe solar cells with over 12% efficiency
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作者 Dae-Ho Son Ha Kyung Park +11 位作者 Dae-Hwan Kim Jin-Kyu Kang Shi-Joon Sung Dae-Kue Hwang Jaebaek Lee Dong-Hwan Jeon Yunae Cho William Jo Taeseon Lee JunHo Kim Sang-Hoon Nam Kee-Jeong Yang 《Carbon Energy》 SCIE EI CAS CSCD 2024年第3期36-52,共17页
Cu2ZnSn(S,Se)4(CZTSSe)solar cells have resource distribution and economic advantages.The main cause of their low efficiency is carrier loss resulting from recombination of photo-generated electron and hole.To overcome... Cu2ZnSn(S,Se)4(CZTSSe)solar cells have resource distribution and economic advantages.The main cause of their low efficiency is carrier loss resulting from recombination of photo-generated electron and hole.To overcome this,it is important to understand their electron-hole behavior characteristics.To determine the carrier separation characteristics,we measured the surface potential and the local current in terms of the absorber depth.The elemental variation in the intragrains(IGs)and at the grain boundaries(GBs)caused a band edge shift and bandgap(Eg)change.At the absorber surface and subsurface,an upward Ec and Ev band bending structure was observed at the GBs,and the carrier separation was improved.At the absorber center,both upward Ec and Ev and downward Ec-upward Ev band bending structures were observed at the GBs,and the carrier separation was degraded.To improve the carrier separation and suppress carrier recombination,an upward Ec and Ev band bending structure at the GBs is desirable. 展开更多
关键词 carrier separation CZTSSe flexible solar cell local current surface potential
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Ultrafast carrier dynamics in GeSn thin film based on time-resolved terahertz spectroscopy
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作者 黄盼盼 张有禄 +3 位作者 胡凯 齐静波 张岱南 程亮 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第1期164-169,共6页
We measure the time-resolved terahertz spectroscopy of GeSn thin film and studied the ultrafast dynamics of its photo-generated carriers.The experimental results show that there are photo-generated carriers in GeSn un... We measure the time-resolved terahertz spectroscopy of GeSn thin film and studied the ultrafast dynamics of its photo-generated carriers.The experimental results show that there are photo-generated carriers in GeSn under femtosecond laser excitation at 2500 nm,and its pump-induced photoconductivity can be explained by the Drude–Smith model.The carrier recombination process is mainly dominated by defect-assisted Auger processes and defect capture.The firstand second-order recombination rates are obtained by the rate equation fitting,which are(2.6±1.1)×10^(-2)ps^(-1)and(6.6±1.8)×10^(-19)cm^(3)·ps^(-1),respectively.Meanwhile,we also obtain the diffusion length of photo-generated carriers in GeSn,which is about 0.4μm,and it changes with the pump delay time.These results are important for the GeSn-based infrared optoelectronic devices,and demonstrate that Ge Sn materials can be applied to high-speed optoelectronic detectors and other applications. 展开更多
关键词 GeSn thin film time-resolved THz spectroscopy ultrafast dynamics carrier recombination
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Experimental Study on Gas Flow Uniformity in a Diesel Particulate Filter Carrier
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作者 Zhengyong Wang Jianhua Zhang +5 位作者 Guoliang Su Peixing Yang Xiantao Fan Shuzhan Bai Ke Sun Guihua Wang 《Fluid Dynamics & Materials Processing》 EI 2024年第1期193-204,共12页
A Diesel Particulate Filter(DPF)is a critical device for diesel engine exhaust products treatment.When using active-regeneration purification methods,on the one hand,a spatially irregular gas flow can produce relative... A Diesel Particulate Filter(DPF)is a critical device for diesel engine exhaust products treatment.When using active-regeneration purification methods,on the one hand,a spatially irregular gas flow can produce relatively high local temperatures,potentially resulting in damage to the carrier;On the other hand,the internal temperature field can also undergo significant changes contributing to increase this risk.This study explores the gas flow uniformity in a DPF carrier and the related temperature behavior under drop-to-idle(DTI)condition by means of bench tests.It is shown that the considered silicon carbide carrier exhibits good flow uniformity,with a temperature deviation of no more than 2%with respect to the same radius measurement point at the outlet during the regeneration stage.In the DTI test,the temperature is relatively high within r/2 near the outlet end,where the maximum temperature peak occurs,and the maximum radial temperature gradient is located between r/2 and the edge.Both these quantities grow as the soot load increases,thereby making the risk of carrier burnout greater.Finally,it is shown that the soot load limit of the silicon carbide DPF can be extended to 11 g/L,which reduces the frequency of active regeneration by approximately 40%compared to a cordierite DPF. 展开更多
关键词 DPF flow uniformity DTI silicon carbide carrier soot load
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Atomic Ni directional-substitution on ZnIn_(2)S_(4) nanosheet to achieve the equilibrium of elevated redox capacity and efficient carrier-kinetics performance in photocatalysis
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作者 Haibin Huang Guiyang Yu +5 位作者 Xingze Zhao Boce Cui Jinshi Yu Chenyang Zhao Heyuan Liu Xiyou Li 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第1期272-281,I0007,共11页
It is a challenge to coordinate carrier-kinetics performance and the redox capacity of photogenerated charges synchronously at the atomic level for boosting photocatalytic activity.Herein,the atomic Ni was introduced ... It is a challenge to coordinate carrier-kinetics performance and the redox capacity of photogenerated charges synchronously at the atomic level for boosting photocatalytic activity.Herein,the atomic Ni was introduced into the lattice of hexagonal ZnIn_(2)S_(4) nanosheets(Ni/ZnIn_(2)S_(4))via directionalsubstituting Zn atom with the facile hydrothermal method.The electronic structure calculations indicate that the introduction of Ni atom effectively extracts more electrons and acts as active site for subsequent reduction reaction.Besides the optimized light absorption range,the elevation of Efand ECBendows Ni/ZnIn_(2)S_(4) photocatalyst with the increased electron concentration and the enhanced reduction ability for surface reaction.Moreover,ultrafast transient absorption spectroscopy,as well as a series of electrochemical tests,demonstrates that Ni/ZnIn_(2)S_(4) possesses 2.15 times longer lifetime of the excited charge carriers and an order of magnitude increase for carrier mobility and separation efficiency compared with pristine ZnIn_(2)S_(4).These efficient kinetics performances of charge carriers and enhanced redox capacity synergistically boost photocatalytic activity,in which a 3-times higher conversion efficiency of nitrobenzene reduction was achieved upon Ni/ZnIn_(2)S_(4).Our study not only provides in-depth insights into the effect of atomic directional-substitution on the kinetic behavior of photogenerated charges,but also opens an avenue to the synchronous optimization of redox capacity and carrier-kinetics performance for efficient solar energy conversion. 展开更多
关键词 ZnIn_(2)S_(4) SUBSTITUTION carrier kinetics Redox capacity PHOTOCATALYSIS
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CO_(2)capture costs of chemical looping combustion of biomass:A comparison of natural and synthetic oxygen carrier
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作者 Benjamin Fleiß Juraj Priscak +3 位作者 Martin Hammerschmid Josef Fuchs Stefan Müller Hermann Hofbauer 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第5期296-310,共15页
Chemical looping combustion has the potential to be an efficient and low-cost technology capable of contributing to the reduction of the atmospheric concentration of CO_(2) in order to reach the 1.5/2°C goal and ... Chemical looping combustion has the potential to be an efficient and low-cost technology capable of contributing to the reduction of the atmospheric concentration of CO_(2) in order to reach the 1.5/2°C goal and mitigate climate change.In this process,a metal oxide is used as oxygen carrier in a dual fluidized bed to generate clean CO_(2) via combustion of biomass.Most commonly,natural ores or synthetic materials are used as oxygen carrier whereas both must meet special requirements for the conversion of solid fuels.Synthetic oxygen carriers are characterized by higher reactivity at the expense of higher costs versus the lower-cost natural ores.To determine the viability of both possibilities,a techno-economic comparison of a synthetic material based on manganese,iron,and copper to the natural ore ilmenite was conducted.The synthetic oxygen carrier was characterized and tested in a pilot plant,where high combustion efficiencies up to 98.4%and carbon capture rates up to 98.5%were reached.The techno-economic assessment resulted in CO_(2) capture costs of 75 and 40€/tCO_(2) for the synthetic and natural ore route respectively,whereas a sensitivity analysis showed the high impact of production costs and attrition rates of the synthetic material.The synthetic oxygen carrier could break even with the natural ore in case of lower production costs and attrition rates,which could be reached by adapting the production process and recycling material.By comparison to state-of-the-art technologies,it is demonstrated that both routes are viable and the capture cost of CO_(2) could be reduced by implementing the chemical looping combustion technology. 展开更多
关键词 Chemical looping combustion BECCS Techno-economic assessment CO_(2)capture costs Oxygen carrier development Synthetic materials ILMENITE
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Mitochondrial carrier homolog 2 increases malignant phenotype of human gastric epithelial cells and promotes proliferation,invasion,and migration of gastric cancer cells
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作者 Jing-Wen Zhang Ling-Yan Huang +3 位作者 Ya-Ning Li Ying Tian Jia Yu Xiao-Fei Wang 《World Journal of Gastrointestinal Oncology》 SCIE 2024年第3期991-1005,共15页
BACKGROUND The precise role of mitochondrial carrier homolog 2(MTCH2)in promoting malignancy in gastric mucosal cells and its involvement in gastric cancer cell metastasis have not been fully elucidated.AIM To determi... BACKGROUND The precise role of mitochondrial carrier homolog 2(MTCH2)in promoting malignancy in gastric mucosal cells and its involvement in gastric cancer cell metastasis have not been fully elucidated.AIM To determine the role of MTCH2 in gastric cancer.METHODS We collected 65 samples of poorly differentiated gastric cancer tissue and adjacent tissues,constructed MTCH2-overexpressing and MTCH2-knockdown cell models,and evaluated the proliferation,migration,and invasion of human gastric epithelial cells(GES-1)and human gastric cancer cells(AGS)cells.The mito-chondrial membrane potential(MMP),mitochondrial permeability transformation pore(mPTP)and ATP fluorescence probe were used to detect mitochondrial function.Mitochondrial function and ATP synthase protein levels were detected via Western blotting.RESULTS The expression of MTCH2 and ATP2A2 in gastric cancer tissues was significantly greater than that in adjacent tissues.Overexpression of MTCH2 promoted colony formation,invasion,migration,MMP expression and ATP production in GES-1 and AGS cells while upregulating ATP2A2 expression and inhibiting cell apoptosis;knockdown of MTCH2 had the opposite effect,promoting overactivation of the mPTP and promoting apoptosis.CONCLUSION MTCH2 can increase the malignant phenotype of GES-1 cells and promote the proliferation,invasion,and migration of gastric cancer cells by regulating mitochondrial function,providing a basis for targeted therapy for gastric cancer cells. 展开更多
关键词 Gastric cancer Mitochondrial carrier homolog 2 ATP synthase ATP2A2 Mitochondrial permeability transformation pore
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Comprehensive study of the ultrafast photoexcited carrier dynamics in Sb_(2)Te_(3)–GeTe superlattices
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作者 叶之江 金钻明 +7 位作者 蒋叶昕 卢琦 贾梦辉 钱冬 黄夏敏 李舟 彭滟 朱亦鸣 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第7期381-387,共7页
Chalcogenide superlattices Sb_(2)Te_(3)-GeTe is a candidate for interfacial phase-change memory(iPCM) data storage devices.By employing terahertz emission spectroscopy and the transient reflectance spectroscopy togeth... Chalcogenide superlattices Sb_(2)Te_(3)-GeTe is a candidate for interfacial phase-change memory(iPCM) data storage devices.By employing terahertz emission spectroscopy and the transient reflectance spectroscopy together,we investigate the ultrafast photoexcited carrier dynamics and current transients in Sb_(2)Te_(3)-GeTe superlattices.Sample orientation and excitation polarization dependences of the THz emission confirm that ultrafast thermo-electric,shift and injection currents contribute to the THz generation in Sb_(2)Te_(3)-GeTe superlattices.By decreasing the thickness and increasing the number of GeTe and Sb_(2)Te_(3) layer,the interlayer coupling can be enhanced,which significantly reduces the contribution from circular photo-galvanic effect(CPGE).A photo-induced bleaching in the transient reflectance spectroscopy probed in the range of~1100 nm to~1400 nm further demonstrates a gapped state resulting from the interlayer coupling.These demonstrates play an important role in the development of iPCM-based high-speed optoelectronic devices. 展开更多
关键词 Sb_(2)Te_(3)/GeTe superlattices ultrafast carrier dynamics interfacial phase change memory THz emission spectroscopy transient reflectance spectroscopy
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Hepatitis B surface antigen clearance in inactive hepatitis B surface antigen carriers treated with peginterferon alfa-2a 被引量:19
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作者 Ming-Hui Li Yao Xie +11 位作者 Lu Zhang Yao Lu Ge Shen Shu-Ling Wu Min Chang Cai-Qin Mu Lei-Ping Hu Wen-Hao Hua Shu-Jing Song Shu-Feng Zhang Jun Cheng Dao-Zhen Xu 《World Journal of Hepatology》 CAS 2016年第15期637-643,共7页
AIM: To examine the association between interferon(IFN) therapy and loss of hepatitis B surface antigen(HBs Ag) in inactive HBs Ag carriers. METHODS: This was a retrospective cohort study in inactive HBs Ag carriers, ... AIM: To examine the association between interferon(IFN) therapy and loss of hepatitis B surface antigen(HBs Ag) in inactive HBs Ag carriers. METHODS: This was a retrospective cohort study in inactive HBs Ag carriers, who were treatment-naive, with a serum HBs Ag level < 100 IU/m L and an undetectable hepatitis B virus(HBV) DNA level(< 100 IU/m L). All the 20 treated patients received subcutaneous PEG-IFN alfa-2a 180 μg/wk for 72 wk and were then followed for 24 wk. There were 40 untreated controls matched with 96 wk of observation. Serum HBs Ag, HBV DNA, and alanine aminotransferases were monitored every 3 mo in the treatment group and every 3-6 mo in the control group. RESULTS: Thirteen(65.0%) of 20 treated patients achieved HBs Ag loss, 12 of whom achieved HBs Ag seroconversion. Mean HBs Ag level in treated patients decreased to 6.69 ± 13.04 IU/m L after 24 wk of treatment from a baseline level of 26.22 ± 33.00 IU/m L. Serum HBV DNA level remained undetectable(< 100 IU/m L) in all treated patients during the study. HBs Ag level of the control group decreased from 25.72 ± 25.58 IU/m L at baseline to 17.11 ± 21.62 IU/m L at week 96(P = 0.108). In the control group, no patient experienced HBs Ag loss/seroconversion, and two(5.0%) developed HBV reactivation.CONCLUSION: IFN treatment results in HBs Ag loss and seroconversion in a considerable proportion of inactive HBs Ag carriers with low HBs Ag concentrations. 展开更多
关键词 CHRONIC HEPATITIS B SURFACE ANTIGEN carriers Inactive HEPATITIS B SURFACE ANTIGEN carriers Interfero
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Distribution of carriers in gradient-doping transmission-mode GaAs photocathodes grown by molecular beam epitaxy 被引量:7
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作者 张益军 常本康 +2 位作者 杨智 牛军 邹继军 《Chinese Physics B》 SCIE EI CAS CSCD 2009年第10期4541-4546,共6页
The gradient-doping structure is first applied to prepare the transmission-mode GaAs photocathode and the integral sensitivity of the sealed image tube achieves 1420μA/lm. This paper studies the inner carrier concent... The gradient-doping structure is first applied to prepare the transmission-mode GaAs photocathode and the integral sensitivity of the sealed image tube achieves 1420μA/lm. This paper studies the inner carrier concentration distribution of the gradient-doping transmission-mode GaAs photocathode after molecular beam epitaxy (MBE) growth using the electrochemical capacitance-voltage profiling. The results show that an ideal gradient-doping structure can be obtained by using MBE growth. The total band-bending energy in the gradient-doping GaAs active-layer with doping concentration ranging from 1×10^19 cm-3 to 1×1018 cm-3 is calculated to be 46.3 meV, which helps to improve the photoexcited electrons movement toward surface for the thin epilayer. In addition,by analysis of the band offsets, it is found that the worse carrier concentration discrepancy between GaAs and GaA1As causes a lower back interface electron potential barrier which decreases the amount of high-energy photoelectrons and affects the short-wave response. 展开更多
关键词 GaAs photocathode gradient doping molecular beam epitaxy carrier concentrationdistribution
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Delivering DNA into Plant Cell by Gene Carriers of ZnS Nanoparticles 被引量:4
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作者 FU Yu-qin LI Lu-hua +5 位作者 WANG Pi-wu QU Jing FU Yong-ping WANG Hui SUN Jing-ran LÜ Chang-li 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 2012年第4期672-676,共5页
The development of nanotechnology provides a new method for genetic engineering.However,the nanoparticles as gene carriers have been mainly used in the mammalian cells so far.We observed that ZnS nanoparticles modifie... The development of nanotechnology provides a new method for genetic engineering.However,the nanoparticles as gene carriers have been mainly used in the mammalian cells so far.We observed that ZnS nanoparticles modified with positively charged poly-L-lysine(PLL) successfully delivered GUS-encoding plasmid DNA into tobacco cells by means of ultrasound-assisted method.Polymerase chain reaction(PCR) detection,Southern blot analysis and GUS histochemical staining were carried out for the regenerated plants.The stable genetic modified plants mediated by ZnS nanoparticles can be obtained.This article demonstrates the great potential of nanoparticles as gene carrier in plant transformation and proves a novel approach for plant genetic decoration. 展开更多
关键词 ZnS nanoparticle Gene carrier TRANSFORMATION TOBACCO Stable expression
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Carriers′carriers结构的BGP/MPLS VPN解决方案 被引量:1
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作者 谷志慧 张思东 张宏科 《现代电子技术》 2005年第23期99-101,共3页
Carriers′carriers的BGP/MPLSVPN是一种递归嵌套的VPN网络结构。在分析了现有IPv4网络中其实现方法与不足的基础上,利用BGP的权能属性及多协议扩展属性,提出了一种在IPv4/v6混合网络中,基于跨域Carriers′carri-ers结构的BGP/MPLSVPN... Carriers′carriers的BGP/MPLSVPN是一种递归嵌套的VPN网络结构。在分析了现有IPv4网络中其实现方法与不足的基础上,利用BGP的权能属性及多协议扩展属性,提出了一种在IPv4/v6混合网络中,基于跨域Carriers′carri-ers结构的BGP/MPLSVPN解决方案。该方案以在核心骨干网及VPN承载网络中增设路由反射器为思路,能够很好地解决各级VPN的路由学习及业务流转发。 展开更多
关键词 carriers'-carriers BGP/MPLS VPN IPv4/v6混合网络 路由反射器
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Blind Channel Identification for Cyclic-Prefixed MIMO-OFDM Systems with Virtual Carriers 被引量:3
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作者 Jung-Lang Yu Biling Zhang +1 位作者 Yipu Yuan Wei-Ting Hsu 《China Communications》 SCIE CSCD 2020年第3期101-116,共16页
This paper applies the repetition index scheme(RIS)to the channel identification of cyclic prefixed(CP)multiple-input multiple-output orthogonal frequency division multiplexing(MIMO-OFDM)systems with virtual carriers(... This paper applies the repetition index scheme(RIS)to the channel identification of cyclic prefixed(CP)multiple-input multiple-output orthogonal frequency division multiplexing(MIMO-OFDM)systems with virtual carriers(VCs)in the environment of the number of receive antennas being no less than that of transmit antennas.The VCs will cause a rank deficiency problem in computing the subspace information.With the subcarrier mapping matrix,the received signal is simplified to remove the rank deficiency.We use the RIS scheme to generate many times of equivalent symbols so the channel identification can converge with few received OFDM blocks.The RIS scheme will convert the white noise into non-white noise.With the Cholesky factorization,a noise whitening technique is developed to turn the non-white noise back to white noise.We further analyze the necessary conditions of identifiability of channel estimation.Simulations are performed to show the superiority of the proposed method. 展开更多
关键词 OFDM MIMO VIRTUAL carrier CHANNEL identification Cholesky FACTORIZATION
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Liquid organic hydrogen carriers 被引量:12
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作者 Teng He Qijun Pei Ping Chen 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2015年第5期587-594,共8页
The development of efficient hydrogen storage materials is one of the biggest technical challenges for the coming "hydrogen economy". The liquid organic hydrogen carriers (LOHCs) with high hydrogen contents, rever... The development of efficient hydrogen storage materials is one of the biggest technical challenges for the coming "hydrogen economy". The liquid organic hydrogen carriers (LOHCs) with high hydrogen contents, reversibilities and moderate dehydrogenation kinetics have been considered as an alternative option supplementing the extensively investigated inorganic hydride systems. In this review, LOHCs for long distance H2 transport and for onboard application will be discussed with the focuses of the design and development of LOHCs and their hydrogenation & dehydrogenation catalyses. 展开更多
关键词 Liquid organic hydrogen carrier CycloalkanesHeterocycleFormic acid Catalysis
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