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84篇 您的检索式:作者名="LI MingFeng"
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1Hypoxic preconditioning stimulates angiogenesis in ischemic penumbra after acute cerebral infarction显示文摘Previous studies have demonstrated the protective effect of hypoxic preconditioning on acute cerebral infarction,but the mechanisms underlying this protection remain unclear.To investigate the protective mechanisms of hypoxic preconditioning in relation to its effects on angiogenesis,we induced a photochemical model of cerebral infarction in an inbred line of mice(BALB/c).Mice were then exposed to hypoxic preconditioning 30 minutes prior to model establishment.Results showed significantly increased vascular endothelial growth factor and CD31 expression in the ischemic penumbra at 24 and 72 hours post infarction,mainly in neurons and vascular endothelial cells.Hypoxic preconditioning increased vascular endothelial growth factor and CD31 expression in the ischemic penumbra and the expression of vascular endothelial growth factor was positively related to that of CD31.Moreover,hypoxic preconditioning reduced the infarct volume and improved neurological function in mice.These findings indicate that the protective role of hypoxic preconditioning in acute cerebral infarction may possibly be due to an increase in expression of vascular endothelial growth factor and CD31 in the ischemic penumbra,which promoted angiogenesis.Sijie Li Yanbo Zhang Guo Shao Mingfeng Yang Jingzhong Niu Guowei Lv Xunming Ji 2013Neural Regeneration Research2013,8,31:31
2Gabapentin inhibits central sensitization during migraine显示文摘Peripheral and central sensitizations are phenomena that occur during migraine.The role of gabapentin,a migraine preventive drug,on central sensitization remains unclear.In this study,a rat model of migraine was established by electrical stimulation of the trigeminal ganglion,and the animals were given intragastric gabapentin.Changes in amino acid content in the cerebrospinal fluid and protein kinase C membrane translocation in the spinal trigeminal nucleus were examined to clarify the mechanisms underlying the efficacy of gabapentin in the treatment of central sensitization during migraine.Electrophysiology,liquid chromatography-mass spectrometry and western blot analysis results revealed that gabapentin reduces neuronal excitability in the spinal nucleus in the trigeminal nerve,decreases excitatory amino acid content and inhibits the activation of protein kinase C.This provides evidence that excitatory amino acids and protein kinase C are involved in the formation and maintenance of central sensitization during migraine.Gabapentin inhibits migraine by reducing excitatory amino acid content in the cerebrospinal fluid and inhibiting protein kinase C activation.Yanbo Zhang Guo Shao Wei Zhang Sijie Li Jingzhong Niu Dongmei Hu Mingfeng Yang Xunming Ji 2013Neural Regeneration Research2013,8,32:12
3Daily variation characteristics of CO2 emission fluxes and contributions of environmental factors in semiarid grassland of Inner Mongolia, China显示文摘Fixed field experimental studies are carried out on daily variations of the undis- turbed community and soil respiration fluxes in different phenological phases of 2001―2002 in semiarid Aneurolepidium chinense steppe of Inner Mongolia, China using static black chamber method. Corresponding statistical analysis of the contributions of the water-heat factors (air temperature, ground temperature, surface soil water content) and ecological factors (above- ground biomass, underground biomass, litter biomass) to daily variation law of the undisturbed community and soil respiration fluxes as well as differences in daily respiration are also con- ducted. The results indicate that undisturbed community and soil respiration have apparent daily variation laws, daily variation patterns of respiration fluxes during different phenological phases are basically the same, and the variations of environmental factors only exert effect on CO2 emission intensities, while the effect on daily variation pattern of grassland CO2 emission fluxes is relatively small. The daily total respiration of the undisturbed community in different phenological phases ranges from 1.34―10.13 g·m?2; soil daily total respiration ranges from 0.98―5.17 g·m?2; both daily variations of undisturbed community and soil respiration fluxes are significantly corre- lated (p < 0.05) or extremely significantly correlated (p < 0.01) with air temperatures and ground surface temperatures, but the correlativity with the soil temperature at 5 and 10 cm depths is relatively weak; multiple regression analysis indicates that about 80% of the difference in daily respiration of the undisturbed community among different phenological phases is induced by the variation of the aboveground biomass, while the variations of the remaining factors can jointly explain around 20% of the daily respiration variations of the whole grassland ecosystem; about 83% of the soil daily respiration variation of the different phenological phases is caused by 0―20 cm underground biomass. Besides, surface soil water content is also an important environmental factor affecting soil daily respiration variations of the Aneurolepidium chinense steppe, but its partial correlation coefficient with soil daily respiration amount does not reach the significance level of 0.05.QI Yuchun DONG Yunshe LIU Jiyuan GENG Yuanbo LI Mingfeng YANG Xiaohong LIU Lixin 2005Science China Earth Sciences2005,48,7:11
4Acute calculous cholecystitis associated with hepatic artery pseudoaneurysm after percutaneous transhepatic gallbladder drainage in a diabetic patient显示文摘Patients with acute calculous cholecystitis are usually undertaken surgery laparoscopic cholecystectomy.However,there are controversies about the decision of operation for patients with high risk factors.Percutaneous transhepatic gallbladder drainage (PTGD) is palliative therapy to alleviate symptoms and physical signs.Since improved clinical outcome has been observed for PTGD,it was recommended as an initial therapeutic option for high risk patients who might need surgery.1 Percutaneous drainage in acute calculous cholecystitis for high risk patients is to be a safe and successful treatment option for patients less eligible for surgery.2 PTGD is relatively safe,but has certain complications.We provided a case report of acute calculous cholecystitis associated with hepatic artery pseudoaneurysm after PTGD in a diabetes mellitus patient.The liver vascular pseudoaneurysms and secondary changes of liver were documented by the imaging examination.The complex interactions among inflammation,bleeding,and diabetes mellitus were involved in this case.Tian Hu Xia Mingfeng Zhang Shuai Li Jie Liu Ju 2014Chinese Medical Journal2014,,17:9
5Design of the Metal Precursors Molecular Structures in Impregnating Solutions for Preparation of Efficient Ni Mo/Al_2O_3 Hydrodesulfurization Catalysts显示文摘The molecular structures of metal precursors in the impregnating solution were designed so as to prepare efficient Ni Mo/Al_2O_3 hydrodesulfurization(HDS) catalysts. At first, five typical impregnating solutions were designed; the existing metal precursors, such as [Mo4(citrate)2O11]^(4-)-like, [P2Mo18O62]^(6-)-like and [P2Mo5O23]^(6-)-like species in the solutions were confirmed by laser Raman spectroscopy(LRS). The UV-Vis spectra results indicated that the solutions containing both phosphoric acid and citric acid could change the existing form of nickel species. Five corresponding Ni Mo/Al_2O_3 catalysts were prepared by the incipient wetness impregnation method. The LRS analysis results of dried catalysts showed that the above metal precursors could be partly retained on alumina support after impregnation and drying, although the interface reaction between different metal precursors and alumina support unavoidably took place. Then the catalysts were sulfided and characterized by N2 physisorption, TEM and XPS analyses. The results showed that different metal precursors in impregnating solution could mainly result in the difference in both the morphology of(Ni)Mo S2 slabs and the promoting effect of Ni species. The catalyst prepared mainly with [P2Mo5O23]^(6-)-like species used as precursors exhibited worse dispersion of(Ni)Mo S2 slabs and lower ratio of Ni–Mo–S active phases than the one with [Mo4(citrate)2O11]^(4-)-like species. Promisingly, the catalyst prepared with co-existing [Mo4(citrate)2O11]^(4-)-like, [P2Mo18O62]^(6-)-like and [P2Mo5O23]^(6-)-like species showed better hydrodesulfurization activity for 4,6-DMDBT thanks to its more well-dispersed Ni–Mo–S active phases.Li Huifeng Li Mingfeng Chu Yang Liu Feng Nie Hong 2015China Petroleum Processing & Petrochemical Technology2015,17,4:8
6Crosstalk-free achromatic full Stokes imaging polarimetry metasurface enabled by polarization-dependent phase optimization显示文摘Imaging polarimetry is one of the most widely used analytical technologies for object detection and analysis.To date,most metasurface-based polarimetry techniques are severely limited by narrow operating bandwidths and inevitable crosstalk,leading to detrimental effects on imaging quality and measurement accuracy.Here,we propose a crosstalkfree broadband achromatic full Stokes imaging polarimeter consisting of polarization-sensitive dielectric metalenses,implemented by the principle of polarization-dependent phase optimization.Compared with the single-polarization optimization method,the average crosstalk has been reduced over three times under incident light with arbitrary polarization ranging from 9μm to 12μm,which guarantees the measurement of the polarization state more precisely.The experimental results indicate that the designed polarization-sensitive metalenses can effectively eliminate the chromatic aberration with polarization selectivity and negligible crosstalk.The measured average relative errors are 7.08%,8.62%,7.15%,and 7.59%at 9.3,9.6,10.3,and 10.6μm,respectively.Simultaneously,the broadband full polarization imaging capability of the device is also verified.This work is expected to have potential applications in wavefront detection,remote sensing,light-field imaging,and so forth.Yaxin Zhang Mingbo Pu Jinjin Jin Xinjian Lu Yinghui Guo Jixiang Cai Fei Zhang Yingli Ha Qiong He Mingfeng Xu Xiong Li Xiaoliang Ma Xiangang Luo 2022Opto-Electronic Advances2022,5,11:6
7Development and CommercialApplication of RSDS-II Technology for Selective Hydrodesulfurization of FCC Naphtha显示文摘The FCC naphtha selective hydrodesulfurization technology(RSDS-II)has been tested with different feedstocks in pilot scale.The results show that RSDS-II technology is viable in terms of its adaptability to different feedstocks.To produce gasoline with a sulfur content of less than 50μg/g by the RSDS-II technology,the gasoline RON loss is less than 1.8,0.9and 0.2 units,respectively,upon processing the conventional high-sulfur and high-olefin FCC naphtha,the high-sulfur MIP naphtha,and the medium-sulfur or low-sulfur MIP naphtha.Upon using the naphtha produced from pre-hydrotreated FCC feedstock as the RSDS-II feedstock to manufacture gasoline with a sulfur content of lower than 10μg/g,the RON loss does not exceed 1.0 unit.The RSDS-II technology has been commercialized successfully at many refineries.The result of operating commercial RSDS-II unit at the Shanghai Petrochemical Company has revealed that upon processing a feedstock containing 38.7 v% —43.3 v% of olefins and 250—470 mg/g of sulfur,the sulfur content in the treated gasoline ranges from 33μg/g to 46μg/g and the RON loss is equal to only 0.3—0.6 units.Till now this RSDS-II unit has been operating smoothly over 30 months.Thanks to its high HDS activity and good selectivity,the RSDS-II technology can meet the refinery’s needs for adequate upgrading of gasoline.Qu Jinhua Xi Yuanbing Li Mingfeng Pan Guangcheng Jin Xin Gao Xiaodong Nie Hong 2013China Petroleum Processing & Petrochemical Technology2013,15,3:6
8Cooperation of PprI and DrRRA in response to extreme ionizing radiation in Deinococcus radiodurans显示文摘Deinococcus radiodurans possesses extreme resistance to ionizing radiation,and has been engineered for the remediation of toxic components in radioactive environments.We have previously shown that PprI(also named IrrE)and DrRRA are essential for the DNA protection and repair pathways that respond to ionizing radiation stress in this species.Here,we investigated the combined roles of PprI and DrRRA in resistance to gamma radiation(800 Gy).The double mutant,△drRRA△pprI,was more sensitive to gamma rays than either△drRRA or△pprI single mutants,and exhibited an elevated level of intracellular protein carbonylation,an extended delay in genome reconstitution and reduced transcriptional levels of certain DNA protection and repair proteins,such as kat,sod,recA and pprA.Interestingly,the induction of DrRRA by ionizing radiation was partially inhibited by the deletion of pprI. Taken together,these results suggest that DrRRA and PprI might have collaborative roles in the response of D.radiodurans to extreme ionizing radiation.WANG LiangYan YIN LongFei XU GuangZhi LI MingFeng ZHANG Hui TIAN Bin HUA YueJin 2012Chinese Science Bulletin2012,57,1:6
9Development of New Generation Catalysts for Selective Hydrodesulfurization of FCC Naphtha显示文摘The influence of active metal components of catalyst, additives and catalyst preparation method on the reactivity of catalyst for selective hydrodesulfurization (HDS) of FCC naphtha was investigated, and the RSDS-21 catalyst with high HDS performance and the RSDS-22 catalyst with high selectivity were developed by RIPP. The composite loading of a new series of catalysts for selective HDS of FCC gasoline has demonstrated excellent desulfurization activity and selectivity and can under conventional hydrotreating conditions manufacture clean gasoline product meeting the national IV emission standard and the Euro V emission standard with less loss in antiknock index. The finalized new series of FCC catalysts upon being adopted for selective HDS of FCC naphtha have good adaptability to different feedstocks along with good stability.Chu Yang Li Mingfeng Li Huifeng Qu Jinhua Nie Hong Li Dadong (Research Institute of Petroleum Processing, SINOPEC Corp., Beijing 100083) 2009China Petroleum Processing & Petrochemical Technology2009,11,1:5
10Development and Application of Hydrocracking Catalysts RHC-1/RHC-5 for Maximizing High Quality Chemical Raw Materials Yield显示文摘To adapt to the change in the demand of the oil refining market,two hydrocracking catalysts,RHC-1 and RHC-5,were developed to improve the quality of tail oil.The catalysts were designed based on the theory of selective ring-opening.By selecting more acidic molecular sieves,the problem of poor selectivity of conventional materials can be solved to properly match up to the hydrogenation performance of catalysts.Compared with the performance of previous catalysts,the quality of the tail oil achieved by the said catalysts is better,and the BMCI is reduced by 1—2 units.In the long cycle operation of the petroleum industry,the good quality of the tail oil has been verified and the adaptability of the process conditions is good.When the RHC-1 catalyst is used to process heavy feed under medium pressure,a BMCI value of about12 can be obtained along with a nearly 60%yield of tail oil.The total yield of chemical raw material(steaming cracking feed+catalytic reforming feed)can exceed 80%,and the hydrogen consumption has dropped by nearly 50%as compared to the conventional hydrocracking conversion rate.When processing a mixed CGO and VGO feed with the full conversion mode under a hydrogen pressure of 13.0 MPa,the RHC-5 catalyst can yield about 68.4%of heavy naphtha with a potential aromatic content of up to 50.6,while the total yield of chemical raw materials can reach more than 98%.The results of industrial application of these catalysts show that more than 30%of high quality tail oil can be obtained via processing of inferior quality feed,and its BMCI value can reach 10.7.The total yield of chemical raw materials can reach more than65%.The industrial operation process has implemented two operating cycles totaling 8 years.Mao Yichao Nie Hong Li Mingfeng Hu Zhihai Zhao Guangle Zhao Yang 2018China Petroleum Processing & Petrochemical Technology2018,20,2:5
11Discrimination of False Negative Results in RT-PCR Detection of SARS-CoV-2 RNAs in Clinical Specimens by Using an Internal Reference显示文摘Reverse transcription-polymerase chain reaction(RT-PCR)is an essential method for specific diagnosis of SARS-CoV-2 infection.Unfortunately,false negative test results are often reported.In this study,we attempted to determine the principal causes leading to false negative results of RT-PCR detection of SARS-CoV-2 RNAs in respiratory tract specimens.Multiple sputum and throat swab specimens from 161 confirmed COVID-19 patients were tested with a commercialfluorescent RT-PCR kit targeting the ORF1 ab and N regions of SARS-CoV-2 genome.The RNA level of a cellular housekeeping gene ribonuclease P/MRP subunit p30(RPP30)in these specimens was also assessed by RT-PCR.Data for a total of 1052 samples were retrospectively re-analyzed and a strong association between positive results in SARS-CoV-2 RNA tests and high level of RPP30 RNA in respiratory tract specimens was revealed.By using the ROC-AUC analysis,we identified Ct cutoff values for RPP30 RT-PCR which predicted false negative results for SARS-CoV-2 RT-PCR with high sensitivity(95.03%–95.26%)and specificity(83.72%–98.55%)for respective combination of specimen type and ampli-fication reaction.Using these Ct cutoff values,false negative results could be reliably identified.Therefore,the presence of cellular materials,likely infected host cells,are essential for correct SARS-CoV-2 RNA detection by RT-PCR in patient specimens.RPP30 could serve as an indicator for cellular content,or a surrogate indicator for specimen quality.In addition,our results demonstrated that false negativity accounted for a vast majority of contradicting results in SARS-CoV-2 RNA test by RT-PCR.Yafei Zhang Changtai Wang Mingfeng Han Jun Ye Yong Gao Zhongping Liu Tengfei He Tuantuan Li Mengyuan Xu Luping Zhou Guizhou Zou Mengji Lu Zhenhua Zhang 2020Virologica Sinica2020,35,6:5
12Engineered trimeric ACE2 binds viral spike protein and locks it in'Thfee-up'conformation to potently inhibit SARS-CoV-2 infection显示文摘Dear Editor,Coronavirus disease 2019(COVID-19)caused by severe acute respiratory syndrome coronavirus 2(SARS-CoV-2)has resulted in a severe global pandemic Following SARS-CoV,SARS-CoV-2 is yet another emerge nt beta-coronavirus threate ning human health.1 However,seventeen years after the SARS pandemic,no targeted vaccines or therapeutics have been approved for SARS,while some of them might have held promise for treating COVID-19.Many neutralizing antibodies against SARS-CoV-2 are currently being developed.However,RNA viruses are known to have high mutation rates.Liang Guo Wenwen Bi Xinling Wang Wei Xu Renhong Yan Yuanyuan Zhang Kai Zhao Yaning Li Mingfeng Zhang Xia Cai Shibo Jiang Youhua Xie Qiang Zhou Lu Lu Bobo Dang 2021Cell Research2021,31,1:5
13A DFT Study on the Adsorption Behavior of Sulfur and Nitrogen Compounds on the NiMoS Phase显示文摘The density functional theory(DFT)with dispersion corrections was used to study the adsorption behavior of sulfur and nitrogen compounds on NiMoS phase.The calculations were performed based on a hexagonal cluster model including the Mo-edge,the S-edge,and the rarely mentioned corner site.It was found that the adsorption of quinoline is stronger than that of benzothiophene at all the active sites.It indicated the origin of the inhibition effect of nitrogen compounds on HDS.And Ni atoms located around Mo-edge and corner site exhibit higher adsorption selectivity to sulfur compounds than the nitrogen ones.It means that the increase in Ni-promoting effect may weaken the inhibition effect of nitrogen compounds on HDS.Wang Wei Li Huifeng Han Wei Zhang Le Zhao Xiaoguang Li Mingfeng 2020China Petroleum Processing & Petrochemical Technology2020,22,1:5
14Study on Sulfidation Degree and Morphology of MoS_2 Catalyst Derived from Various Molybdate Precursors显示文摘The MoS_2 catalysts were prepared from various molybdate precursors including inorganic and organic molybdate compounds. The sulfidation degree and morphology of active phases of MoS_2 activated by various molybdate precursors in H_2S/H_2 stream at different temperatures were studied by X-ray photoelectron spectroscopy(XPS) and high-resolution transmission electron microscopy(HRTEM). The organic molybdate precursors lead to MoS_2 catalysts with higher sulfidation degree and smaller active phases to demonstrate higher catalytic activity during hydrodesulfurizaiton(HDS) of 4,6-DMDBT.Zhang Le Li Mingfeng Nie Hong 2014China Petroleum Processing & Petrochemical Technology2014,16,2:4
15Performance Analysis of Uplink Massive Spatial Modulation MIMO Systems in Transmit-Correlated Rayleigh Channels显示文摘In this paper,the performance of uplink multiuser massive multiple-input multipleoutput(MIMO)system with spatial modulation over transmit-correlated Rayleigh fading channel is investigated,where a large number of antennas are deployed at the base station and linear zero-forcing(ZF)receiver is employed for detection.By taking the transmit correlation and the randomness of shadow fading in to account,the bit error rate(BER)performance of the system is analyzed.According to the performance analysis,an approximated expression of overall average BER of the system is attained.Besides,asymptotic performance is studied and the corresponding BER expression at high signal-to-noise ratio is derived.On this basis,the diversity gain of the system can be obtained for performance evaluation.Simulation results show that the derived theoretical expressions match the simulated values well,which verifies the correctness of our analysis.Qiyishu Li Xiangbin Yu Mingfeng Xie Ning Li Xiaoyu Dang 2021China Communications2021,18,2:4
16Thioetherification of isoprene and butanethiol on transition metal phosphides显示文摘Thioetherification between mercaptan and diolefin is an efficient process to remove mercaptans in FCC gasoline at mild condition, during which the selective hydrogenation of diolefin to monoolefin is also expected. Here, Si O2 supported transition metal(Fe, Co, Ni, Mo and W) phosphides were tested for the thioetherification of isoprene and butanethiol on a fixed-bed reactor at 120 °C and 1.5 MPa H2, and their structure before and after reaction was characterized by means of XRD, HRTEM, N2 sorption, CO chemisorption, NH3-TPD, XPS and TG. It was found that, among different metal phosphides, Mo P/Si O2 showed the best performance, and the optimal nominal Mo P loading was 25%. Apart from the nature of metal, the density of metal and acid sites determined the catalyst performance. Metal site was mainly responsible for hydrogenation of isoprene, while acid site dominantly contributed to the thioetherification and the polymerization of olefins. Moreover, a balance between metallic and acidic functions is required to arrive at a desired performance. Excessive metal sites or acid sites led to the over-hydrogenation of isoprene or the severe polymerization of olefins, respectively. 25%Mo P/Si O2 was tested for 37 h time on stream, and butanethiol conversion maintained at 100%; although isoprene conversion remarkably decreased, the selectivity to isopentenes exceeded 80% after reaction for 11 h. We suggest that the deactivation of Mo P/Si O2 is mainly ascribed to the butanethiol poisoning and the carbonaceous deposit, especially the former.Tianyu Ren Mingfeng Li Yang Chu Jixiang Chen 2018Journal of Energy Chemistry2018,27,3:3
172022 Chinese expert consensus and guidelines on clinical management of toxicity in anti-CD19 chimeric antigen receptor T-cell therapy for B-cell non-Hodgkin lymphoma显示文摘Adoptive cellular immunotherapy with chimeric antigen receptor(CAR)T cells has emerged as a novel modality for treating relapsed and/or refractory B-cell non-Hodgkin lymphoma(B-NHL).With increasing approval of CAR T-cell products and advances in CAR T cell therapy,CAR T cells are expected to be used in a growing number of cases.However,CAR T-cell-associated toxicities can be severe or even fatal,thus compromising the survival benefit from this therapy.Standardizing and studying the clinical management of these toxicities are imperative.In contrast to other hematological malignancies,such as acute lymphoblastic leukemia and multiple myeloma,anti-CD19 CAR T-cell-associated toxicities in B-NHL have several distinctive features,most notably local cytokine-release syndrome(CRS).However,previously published guidelines have provided few specific recommendations for the grading and management of toxicities associated with CAR T-cell treatment for B-NHL.Consequently,we developed this consensus for the prevention,recognition,and management of these toxicities,on the basis of published literature regarding the management of anti-CD19 CAR T-cell-associated toxicities and the clinical experience of multiple Chinese institutions.This consensus refines a grading system and classification of CRS in B-NHL and corresponding measures for CRS management,and delineates comprehensive principles and exploratory recommendations for managing anti-CD19 CAR T-cell-associated toxicities in addition to CRS.Ping Li Yang Liu Yun Liang Jian Bo Sujun Gao Yongxian Hu Yu Hu He Huang Xiaojun Huang Hongmei Jing Xiaoyan Ke Jianyong Li Yuhua Li Qifa Liu Peihua Lu Heng Mei Ting Niu Yongping Song Yuqin Song Liping Su Sanfang Tu Jianxiang Wang Depei Wu Zhao Wang Kailin Xu Zhitao Ying Qingming Yang Yajing Zhang Fengxia Shi Bin Zhang Huilai Zhang Xi Zhang Mingfeng Zhao Weili Zhao Xiangyu Zhao Liang Huang Jun Zhu Wenbin Qian Weidong Han Aibin Liang 2023Cancer Biology & Medicine2023,20,2:3
18Preferential Surface Decoration of Supported Co Catalysts with Pt for Aromatic Saturation显示文摘To explore the ideal architecture of Pt-Co bimetallic catalyst for aromatics saturation, various Pt-Co bimetallic catalysts were synthesized via the galvanic replacement, the co-impregnation, and the sequential impregnation methods, and were characterized by CO chemisorption, transmission electron microscopy(TEM), H_2-temperature-programmed reduction(H_2-TPR), H_2-temperature-programmed desorption(H_2-TPD), X-ray fluorescence(XRF) spectrometry, and inductively coupled plasma atomic emission spectroscopy(ICP-AES), while the catalysts were evaluated by the flow reactor study of toluene hydrogenation. These characterization results suggest that the surface decoration of Pt has little influence on the number of active sites located on the surfaces of the reduced Co-based catalysts, but can greatly suppress the oxidation of Co at room temperature and provide the activated hydrogen at a relatively low temperature. It is demonstrated that their chemical properties and catalytic performance are largely dependent on the location of Pt atoms in the bimetallic catalysts. The architecture of Pt-Co bimetallic catalyst consisting of Co/SiO_2 decorated with 0.3% of Pt, with the most of Pt atoms being situated on the surfaces of Co nanoparticles, is the active structure for aromatic saturation and has the maximum utilization of Pt.Zheng Renyang Zheng Peng Dong Xiao Zheng Aiguo Li Huifeng Li Mingfeng 2018China Petroleum Processing & Petrochemical Technology2018,20,1:2
19Deoxygenation of methyl laurate to hydrocarbons on silica-supported Ni-Mo phosphides: Effect of calcination temperatures of precursor显示文摘SiO2-supported Ni-Mo bimetallic phosphides were prepared by temperature-programmed reduction(TPR) method from the phosphate precursors calcined at different temperatures. Their properties were characterized by means of ultraviolet-visible diffuse reflectance spectroscopy(UV-Vis DRS), H2temperature-programmed reduction(H2-TPR), X-ray diffraction(XRD), transmission electron microscopy(TEM), CO chemisorption, H2 and NH3temperature-programmed desorptions(H2-TPD and NH3-TPD). Their catalytic performances for the deoxygenation of methyl laurate were tested in a fixed-bed reactor. When the precursors were calcined at 400 and 500?C, respectively, Ni Mo P2 phase could be formed apart from Ni2 P and Mo P phases in the prepared C400 and C500 catalysts. However, when the precursors were calcined at600, 700 and 800°C, respectively, only Ni2 P and Mo P phases could be detected in the prepared C600, C700 and C800 catalysts. Also, in C400, C500 and C600 catalysts, Mo atoms were found to be entered in the lattice of Ni2 P phase, but the entering extent became less with the increase of calcination temperature. As the calcination temperature of the precursor increased, the interaction between Ni and Mo in the prepared catalysts decreased, and the phosphide crystallite size tended to increase, subsequently leading to the decrease in the surface metal site density and the acid amount. C600 catalyst showed the highest activity among the tested ones for the deoxygenation of methyl laurate. As the calcination temperature of the precursor increased, the selectivity to C12 hydrocarbons decreased while the selectivity to C11 hydrocarbons tended to increase. This can be mainly attributed to the decreased Ni-Mo interaction and the increased phosphide particle size. In sum, the structure and performance of Ni-Mo bimetallic phosphide catalyst can be tuned by the calcination temperature of precursor.Zhengyi Pan Rijie Wang Mingfeng Li Yang Chu Jixiang Chen 2015Journal of Energy Chemistry2015,24,1:2
20Tocilizumab in patients with moderate or severe COVID-19: a randomized, controlled, open-label, multicenter trial显示文摘Tocilizumab has been reported to attenuate the“cytokine storm”in COVID-19 patients.We attempted to verify the effectiveness and safety of tocilizumab therapy in COVID-19 and identify patients most likely to benefit from this treatment.We conducted a randomized,controlled,open-label multicenter trial among COVID-19 patients.The patients were randomly assigned in a 1:1 ratio to receive either tocilizumab in addition to standard care or standard care alone.The cure rate,changes of oxygen saturation and interference,and inflammation biomarkers were observed.Thirty-three patients were randomized to the tocilizumab group,and 32 patients to the control group.The cure rate in the tocilizumab group was higher than that in the control group,but the difference was not statistically significant(94.12%vs.87.10%,rate difference 95%CI−7.19%–21.23%,P=0.4133).The improvement in hypoxia for the tocilizumab group was higher from day 4 onward and statistically significant from day 12(P=0.0359).In moderate disease patients with bilateral pulmonary lesions,the hypoxia ameliorated earlier after tocilizumab treatment,and less patients(1/12,8.33%)needed an increase of inhaled oxygen concentration compared with the controls(4/6,66.67%;rate difference 95%CI−99.17%to−17.50%,P=0.0217).No severe adverse events occurred.More mild temporary adverse events were recorded in tocilizumab recipients(20/34,58.82%)than the controls(4/31,12.90%).Tocilizumab can improve hypoxia without unacceptable side effect profile and significant influences on the time virus load becomes negative.For patients with bilateral pulmonary lesions and elevated IL-6 levels,tocilizumab could be recommended to improve outcome.Dongsheng Wang Binqing Fu Zhen Peng Dongliang Yang Mingfeng Han Min Li Yun Yang Tianjun Yang Liangye Sun Wei Li Wei Shi Xin Yao Yan Ma Fei Xu Xiaojing Wang Jun Chen Daqing Xia Yubei Sun Lin Dong Jumei Wang Xiaoyu Zhu Min Zhang Yonggang Zhou Aijun Pan Xiaowen Hu Xiaodong Mei Haiming Wei Xiaoling Xu 2021Frontiers of Medicine2021,15,3:2
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