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PAM-PAA microgel inverse opal photonic crystal and pH response

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Chinese Chemical Letters 2007年第11期18卷 1395-1398页

作者： yong qiang He Xiao Dong Wang Jian Ying Wang Yan Feng yong qiang zhao Xiu Dong You School of Science Tianjin University Tianjin 300072 China Insititute of Medical Equipment Academy of Military Medical Sciences Tianjin 300161 China

The colloidal crystal template or opal with a closed-packed face-centered cubic （fcc） lattice was prepared from monodisperse polystyrene （PS） spheres by vertical sedimentation. The template provided void space for infiltration of monomer precursor composed of acrylate acid, acrylamide and ammonium-persulfate, as well as microgel from the subsequent copolymerization. The sample was immersed in dimethylbenzene for completely removing PS spheres to form PAM inverse opal hydrogels （IOHPAM） or PAM/PAA inverse opal hydrogels （IOHPAM/PAA） photonic crystals. The PS spheres were replaced by air spheres, which interconnected each other through the windows. The study of responses to pH show that there are two peaks for both IOHPAM and IOHPAM/PAA films, but the IOHPAM/PAA peaks shift to higher pH, and the peaks are independent with the AA content.

关键词： Photonic crystal pH response PAM/PAA Opal Inverse opal hydrogel

Effects and mechanisms of fluorite on the co-reduction of blast furnace dust and seaside titanomagnetite

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International Journal of Minerals,Metallurgy and Materials 2017年第11期24卷 1201-1210页

作者： Tian-yang Hu Ti-chang Sun Jue Kou Chao Geng yong-qiang zhao School of Civil and Resources Engineering University of Science and Technology Beijing Beijing 100083 China Key Laboratory of Ministry of Education of China for Efficient Mining and Safety of Metal Mines Beijing 100083 China

The co-reduction roasting and grinding-magnetic separation of seaside titanomagnetite and blast furnace dust was investigated with and without fluorite addition at a reduction roasting temperature of 1250°C for 60 min, a grinding fineness of-43 μm accounting for 69.02 wt% of the total, and a low-intensity magnetic field strength of 151 kA/m. The mineral composition, microstructure, and state of the roasted products were analyzed, and the concentrations of CO and CO_2 were analyzed in the co-reduction roasting. Better results were achieved with a small fluorite dosage(≤4 wt%) in the process of co-reduction. In addition, F^- was found to reduce the melting point and viscosity of the slag phase because of the high content of aluminate and silicate minerals in the blast furnace dust. The low moisture content of the blast furnace dust and calcic minerals inhibited the hydrolysis of CaF_2 and the loss of F^-. Compared with the blast furnace dust from Chengdeng, the blast furnace dusts from Jiugang and Jinxin inhibited the diffusion of F-when used as reducing agents, leading to weaker effects of fluorite.

关键词： seaside titanomagnetite blast furnace dust co-reduction roasting fluorite mechanisms

Effects of calcium compounds on the carbothermic reduction of vanadium titanomagnetite concentrate

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International Journal of Minerals,Metallurgy and Materials 2020年第3期27卷 301-309页

作者： Xiao-hui Li Jue Kou Ti-chang Sun Shi-chao Wu yong-qiang zhao School of Civil and Resource Engineering University of Science and Technology Beijing

Effects of calcium compounds on the carbothermic reduction of vanadium titanomagnetite concentrate(VTC) were investigated. It was found that calcium compounds had great effects on the metallization rate of the reduction product, the order of the metallization rate of reduction product being CaCO3 > no additive > CaSO4 > CaCl2, which indicated that the addition of CaCO3 was more conducive to promoting the reduction of iron than other calcium compounds. Gas analysis showed that there were mainly two processes in the carbothermic reduction of VTC, a solid–solid and a solid–gas reaction. The concentrations of CO and CO2 were highest when CaCO3 was added, while that in a roasting system decreased the most when CaCl2 was added. X-ray diffraction(XRD) analysis showed that calcium compounds could change the reduction process of ilmenite in VTC. The phase compositions of the reduction products were changed from metallic iron(Fe) and anosovite(FeTi2O5) to metallic iron(Fe) and perovekite(CaTiO3) when calcium compounds were added. Additionally, CaSO4 and CaCl2 could significantly promote the growth of metallic iron particles, though the existence of Fe-bearing Mg2TiO4 in reduction products was not conducive to the reduction of iron. The formation of FeS would further hinder the reduction of iron after adding CaSO4.

关键词： vanadium titanomagnetite concentrate calcium compounds carbothermic reduction metallic iron perovekite

Formation of calcium titanate in the carbothermic reduction of vanadium titanomagnetite concentrate by adding CaCO3

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International Journal of Minerals,Metallurgy and Materials 2020年第6期27卷 745-753页

作者： Xiao-hui Li Jue Kou Ti-chang Sun Shi-chao Wu yong-qiang zhao School of Civil and Resource Engineering University of Science and Technology BeijingBeijing 100083China

The formation of calcium titanate in the carbothermic reduction of vanadium titanomagnetite concentrate(VTC)by adding CaCO3 was *** analysis was employed to show the feasibility of calcium titanate formation by the reaction of ilmenite and Ca CO3 in a reductive atmosphere,where ilmenite is more easily reduced by CO or carbon in the presence of *** effects of CaCO3 dosage and reduction temperature on the phase transformation and metallization degree were also investigated in an actual roasting *** increase of CaCO3 dosages and reduction temperatures were found to be conducive to the formation of calcium titanate,and the optimum conditions were a CaCO3 dosage of 18 wt%and a reduction temperature of 1400°***,scanning electron microscopy–energy dispersive spectrometry(SEM–EDS)analysis shows that calcium titanate produced via the carbothermic reduction of VTC by CaCO3 addition was of higher purity with particle size approximately 50μ***,the separation of calcium titanate and metallic iron will be the focus in the future study.

关键词： vanadium titanomagnetite concentrate calcium carbonate carbothermic reduction metallic iron calcium titanate

Dynamic deformylation of 5-formylcytosine and decarboxylation of 5-carboxylcytosine during differentiation of mouse embryonic stem cells into mouse neurons

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Chinese Chemical Letters 2024年第11期35卷 278-283页

作者： Yang Feng Yang-Qing Tian yong-qiang zhao Sheng-Jun Chen Bi-Feng Yuan Key Laboratory of Aquatic Product Processing Ministry of Agriculture and Rural AffairsNational R&D Center for Aquatic Product ProcessingSouth China Sea Fisheries Research InstituteChinese Academy of Fishery SciencesGuangzhou 510300China Department of Occupational and Environmental Health School of Public HealthResearch Center of Public HealthRenmin Hospital of Wuhan UniversityWuhan UniversityWuhan 430071China College of Veterinary Medicine Yunnan Agricultural UniversityKunming 650000China

Regulation of cell fate requires the establishment and erasure of 5-methylcytosine(5mC) in genomic *** formation of 5mC is achieved by DNA cytosine methyltransferases(DNMTs),whereas the removal of5mC can be accomplished by various *** from ten-eleven translocation(TET)-mediated oxidation of 5mC followed by thymine DNA glycosylase(TDG)-initiated base excision repair(BER),the direct deformylation of 5-formylcytosine(5fC) and decarboxylation of 5-carboxylcytosine(5caC) have also been discovered as the novel DNA demethylation *** these novel demethylation pathways have been identified in stem cells and somatic cells,their precise roles in regulating cell fate remain ***,we differentiate mouse embryonic stem cells(mESCs) into mouse embryoid bodies(mEBs),followed by further differentiation into mouse neural stem cells(mNSCs) and finally into mouse neurons(mNeurons).During this sequential differentiation process,we employ probe molecules,namely2'-fluorinated 5-formylcytidine(F-5fC) and 2'-fluorinated 5-carboxyldeoxycytidine(F-5caC),for metabolic *** results of mass spectrometry(MS) analysis demonstrate the deformylation and decarboxylation activities are progressively decreased and increased respectively during differentiation process,and this opposite demethylation tendency is not associated with DNMTs and TETs.

关键词： Metabolic labeling Mass spectrometry DNA demethylation Deformylation Decarboxylation C-C cleavage Mouse embryonic stem cells Differentiation

Studies on Acaricidal Bioactivities of Artemisia annua *** Against Tetranychus cinnabarinus Bois.(Acari:Tetranychidae)

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Agricultural Sciences in China 2008年第5期7卷 577-584页

作者： ZHANG yong-qiang DING Wei zhao Zhi-mo WU Jing FAN Yu-hu College of Plant Protection Southwest University Chongqing 400716 P.R.China

The aim of this study was to determine the best extraction technique, the most suitable solvent, the optimal plant parts, and the acaricidal activities of Artemisia annua L. The petroleum ether （30-60℃）, petroleum ether （60-90℃）, ethanol, acetone, and water parallel and sequenced extracts were obtained from the leaves, stems and roots of different period of A. annua L. in April, May, June, July and September respectively. And then the acaricidal bioactivities against Tetranychus cinnabarinus of all extracts were determined by the slide-capillary method in the laboratory. The results indicated that the acaricidal bioactivities elevated as the development of A. annua plant at the concentration of 5 mg mL-L The general tendency exhibited the sequence of July 〉 June 〉 May 〉 April, but September decreased comparing to July. However, the most effective extracts in five months were all acetone parallel extract of A. annua leaf, and the corrected mortalities treated after 48 h ranged from 74 to 100%. The median lethal concentrations （LC50） against T. cinnabarinus of acetone parallel extracts ofA. annua leaves in September, July, June, May and April were 0.5986, 0.4341, 0.8376, 0.9443 and 1.3817 mg mL^-1, respectively, treated after 48 h. The 13 groups were isolated from acetone extracts ofA. annua leaves in July by column chromatography, both the 1 lth and 12th groups exhibited strong bioactivities. The median lethal concentrations of the 1 lth and 12th groups against T. cinnabarinus were 0.3683 and 0.1586 mg mL^-1, respectively. The acetone parallel extract ofA. annua leaf in July was the most toxic to T. cinnabarinus and the corrected mortality was 100% after 48 h. The acetone parallel extract of the 1 lth and 12th groupswere the most active components, acted as the emphases in further study.

关键词： Artemisia annua Tetranychus cinnabarinus acetone parallel extract bioactivities

Mechanical properties and friction-wear characteristics of VN/Ag multilayer coatings with heterogeneous and transition interfaces

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Transactions of Nonferrous Metals Society of China 2020年第2期30卷 472-483页

作者： yong-qiang zhao yong-tao MU Ming LIU School of Mechatronics Engineering Harbin Institute of TechnologyHarbin 150001China Vehicle Engineering Center Geely Automobile Research InstituteZhejiang Geely Holding Group Co.Ltd.Ningbo 315336China

The heterogeneous multilayer interface of VN/Ag coatings and transition multilayer interface of VN/Ag coatings were prepared on Inconel 781 and Si(100),and the microstructures,mechanical and tribological properties were investigated from 25 to 700℃.The results showed that the surface roughness and average grain size of VN/Ag coatings with transition multilayer interface are obviously larger than those of VN/Ag coatings with heterogeneous multilayer *** coatings with transition multilayer interface have higher adhesion force and hardness than the coatings with heterogeneous multilayer interface,and both coatings can effectively restrict the initiation and propagation of *** coatings have excellent self-adaptive lubricating properties with a decrease of friction coefficient as the temperature increases,but their wear rates reveal a drastic *** phase composition of the worn area of both coatings was investigated,which indicates that a smooth Ag,Magnéli phase(V2O5)and bimetallic oxides(Ag3VO4 and AgVO3)can be responsible to the excellent lubricity of both *** sum up,the coatings with transition multilayer interface have excellent adaptive lubricating properties and can properly control the diffusion rate and release rate of the lubricating phase,indicating that they have great potential in solving the problem of friction and wear of mechanical parts.

关键词： VN/Ag multilayer coatings heterogeneous multilayer interface transition multilayer interface tribological properties friction temperature oxides

Prospective evaluation of heparin-induced thrombocytopenia expert probability and 4T scores in Chinese patients with suspected heparin-induced thrombocytopenia

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Chinese Medical Journal 2019年第12期132卷 1441-1447页

作者： Sen Li Lian-Kai Fan Shu-Jie Wang yong-qiang zhao Department of Hematology Peking Union Medical College HospitalChinese Academy of Medical Sciences and Peking Union Medical CollegeBeijing 100730. China Department of Clinical Laboratory Peking Union Medical College HospitalChinese Academy of Medical Sciences and Peking Union Medical CollegeBeijing 100730China

Background: Diagnosis of heparin-induced thrombocytopenia (HIT) is challenging. This study aimed to compare the diagnostic performance of HIT expert probability (HEP) and 4T scores, and to evaluate the inter-observer reliability for the 4T score in a clinical setting. Methods: This prospective study included HIT-suspected patients between 2016 and 2018. Three hematologists assessed the HEP and 4T scores. Correlations between scores and anti-platelet factor 4 (anti-PF4)/heparin antibodies were evaluated. Receiver operating characteristic curves and area under the curve (AUC) were used to assess the predictive accuracy of these two scoring models. The intraclass correlation coefficient (ICC) was used to assess the inter-observer agreement of 4T scores between residents and hematologists. Results: Of the 89 subjects included, 22 (24.7%) were positive for anti-PF4/heparin antibody. The correlations between antibody titer and either HEP or 4T scores were similar (r = 0.392, P < 0.01 for the HEP score;r = 0.444, P < 0.01 for the 4T score). No significant difference in the diagnostic performance was displayed between these two scores (AUC for the HEP score: 0.778 vs. AUC for the 4T score: 0.741, P = 0.357). Only 72 4T scores were collected from the residents, with a surprisingly low percentage of observers (43.1%) presenting the four individual item scores which made up their 4T score. The AUC of 4T score assessed by residents and hematologists was 0.657 (95% confidence interval [CI]: 536–0.765) and 0.780 (95% CI: 0.667–0.869, P < 0.05), respectively. The ICC of 4T score between residents and hematologists was 0.49 (95% CI: 0.29–0.65, P < 0.01), demonstrating a fair inter-observer agreement. Conclusions: The HEP score does not display a better performance for predicting HIT than the 4T score. With the unsatisfactory completion rate, the inter-observer agreement of 4T score in a tertiary hospital is fair, underscoring the necessity for continuing education for physicians.

关键词： Heparin-induced thrombocytopenia Clinical scoring model 4T score HIT expert probability score

A PILOT TRIAL FOR SEVERE ,REFRACTORY SYSTEMIC AUTOIMMUNE DISEASE WITH STEM CELL TRANSPLANTATION

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Chinese Medical Sciences Journal 2005年第3期20卷 159-165页

作者： Xiao-mei Leng Yan zhao Dao-bing Zhou Huifen Situ Tai-sheng Li Ti Shen yong-qiang zhao Xiao-feng Zeng Feng-chun Zhang Yi Dong Fu-lin Tang Department of Rheumatology Peking Union Medical College Hospital Chinese Academy of Medical Sciences ＆ Peking Union Medical College Beijing 100730

Objective To evaluate the feasibility, efficacy, and safety of high dose immunosuppressive therapy （HDIT） and autolognus hemopoietic stem cell transplantation （HSCT） with CD^34＋ cell selection in patients with severe, refractory autoim mune diseases. Methods Twenty-six patients with persistent systemic lupus erythematosus （SLE）, rheumatoid arthritis （RA）, primary Sjogren＇s syndrome （pSS）, or systemic sclerosis （SSc） who had been treated unsuccessfully with conventional treatment were enrolled in the trial in Peking Union Medical College Hospital from September 1999 to June 2004. The patients received HDIT with 200 mg/kg cyclophosphamide followed by an infusion of autologous stem cells that were CD34 selected. Disease acti- vity, adverse effect, hemopoietic and immune reconstitution, and time to recurrence of disease were monitored. Overall treatment related mortality was 7.7% （2/26） with 1 patient died of cytomegalovirus infection and an other of severe pneumonia. Relapse occurred in 3 SLE patients （17.6%） in 37, 26, and 19 months posttransplantation respectively, and 1 RA patient in 15 months posttransplantation. SLE Disease Activity Index （SLEDAI） scores of SLE survivors decreased significantly （P 〈 0.01）. RA patients recorded a drop of Disease Activity Score 28 （DAS 28）. The pSS patient remained symptoms free up to now, more than 50 months aider the transplantation. Conclusion HSCT can be performed relative safely in patients with severe autoimmune disease. Short-term effect of HSCT is promising. However treatment related mortality and relapse were observed in a subset of patients.

关键词： systemic autoimmune disease hemopoietic stem cell transplantation therapeutics