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19篇 您的检索式:作者名="Jiao Fen"
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1Utilization of polysaccharides as depressants for the flotation separation of copper/lead concentrate显示文摘The interaction mechanism between dextrin and minerals has been investigated through micro-flotation, adsorption density measurements, Fourier transform infrared ray (FTIR) spectroscopic studies and dissolution tests. Dextrin shows a good depressing action towards galena but not chalcopyrite. FTIR spectroscopic studies indicate that dextrin chemically adsorbed on galena surface in alkaline pH range. Dissolution tests confirm leaching action of metal ions from chalcopyrite and galena surfaces, and dextrin-lead ion interaction. Adsorption measurements present that the higher adsorption density of O-isopropyl-N-ethyl thionocarbamate (IPETC) onto chalcopyrite than that onto galena, and IPETC adsorbed on galena decrease with increasing dextrin concentrations in the presence of dextrin, attesting the flotation results.Qin Wenqing Wei Qian Jiao Fen Yang Congren Liu Ruizeng Wang Peipei Ke Lifang 2013International Journal of Mining Science and Technology2013,23,2:16
2Effect of sodium pyrophosphate on the flotation separation of chalcopyrite from galena显示文摘The effect of sodium pyrophosphate (SPH) on the separation of chalcopyrite from galena was examined through flotation, adsorption, electrokinetic studies and infrared spectral analysis. Differential flotation tests indicate that satisfactory separation can be achieved within the pH range from 2.5 to 6 using SPH to depress the galena, but not the chalcopyrite when O-isopropyl-N-ethyl thionocarbamate (IPETC) is used as the collector. The electrophoretic mobilities of both the minerals dramatically become negatively charged following SPH adsorption in the pH range from 2.5 to 12. The infrared spectral analysis suggests that chemical adsorption occurs on galena surface treated by SPH, indicating that a chelate complex has formed. At weakly acidic pH values, the adsorption density of IPETC onto galena is significantly reduced in the presence of SPH. However, the amount of IPETC adsorbed onto chalcopyrite almost remains at the same level. Since the observed adsorption density of IEPTC onto chalcopyrite is quite high compared to galena, the observed flotation results are explained. A possible mechanism for the interaction between the two sulphide minerals and SPH is discussed.Qin Wenqing Wei Qian Jiao Fen Li Ning Wang Peipei Ke Lifang 2012International Journal of Mining Science and Technology2012,22,3:15
3The Role of MicroRNAs in Neural Stem Cells and Neurogenesis显示文摘Neural stem cells give rise to neurons through the process of neurogenesis,which includes neural stem cell proliferation,fate determination of new neurons,as well as the new neuron's migration,maturation and integration.Currently,neurogenesis is divided into two phases:embryonic and adult phases.Embryonic neurogenesis occurs at high levels to form the central nervous system.Adult neurogenesis has been consistently identified only in restricted regions and occurs at low levels.As the basic process for embryonic neurodevelopment and adult brain maintenance,neurogenesis is tightly regulated by many factors and pathways.MicroRNA,short non-coding RNA that regulates gene expression at the post-transcriptional level,appears to be involved in multiple steps of neurogenesis.This review summarizes the emerging role of microRNAs in regulating embryonic and adult neurogenesis,with a particular emphasis on the proliferation and differentiation of neural stem cells.Fen Ji Xiaohui Lv Jianwei Jiao 2013Journal of Genetics and Genomics2013,40,2:11
4Expert consensus on the glycemic management of critically ill patients显示文摘Introduction The incidence of hyperglycemia is 40-60%in critically ill patients and is up to 60-80%in those who have undergone car-diac surgery.[1]The results of an epidemiological study in the United States showed that 28.6%of diabetic patients and 9.3%of non-diabetic patients had elevated mean daily glucose on the day of ICU admission.[2]In critically ill patients,elevated blood glucose is primarily the result of stress,and stress-induced hy-perglycemia is an independent risk factor associated with prog-nosis,regardless of a previous diagnosis of diabetes.Nutritional therapy has become an integral treatment option for patients in the ICU,[3,4]though nearly 30%of patients with enteral nu-trition and 44-50%with parenteral nutrition(PN)experience elevated glucose.[5,6]Intensive insulin therapy(IIT)is an impor-tant treatment for controlling hyperglycemia in critically ill pa-tients,but it also carries a corresponding risk of hypoglycemia.Zhixiong Wu Jiao Liu Dong Zhang Kai Kang Xiangrong Zuo Qianghong Xu Aijun Pan Wei Fang Fen Liu You Shang Haiyan Yin Juntao Hu Jinglun Liu Jiangquan Fu Wei Zhang Yuan Zong Min Shao Feng Zhao Mei Meng Yanfei Mao Yingchuan Li Dechang Chen 2022Journal of Intensive Medicine2022,2,3:9
5Mechanism study on flotation separation of molybdenite from chalcocite using thioglycollic acid as depressant显示文摘Effects of collectors(butyl xanthate(BX), O-isopropyl-N-sulfur ethyl carbamate(Z-200) and emulsified kerosene), dereagent(sodium sulfide) and depressant thioglycollic acid(TGA) on the flotation of chalcocite and molybdenite were investigated through flotation. The first principle theory was adopted to understand the difference of their surfaces and reaction between minerals and reagents. Results of flotation tests revealed that selectivity of emulsified kerosene is the best of three collectors in separation of chalcocite and molybdenite, though the others also display excellent collecting properties. Sodium sulfide can effectively remove collectors adsorbed on chalcocite surface, and TGA is an effective depressant of chalcocite at pH 8-9. Through first principle study, molybdenite displays relatively stronger covalence property while bonding interaction between copper atoms in chalcocite enhanced its ionicity. Bonding interaction is weaker in reaction of TGA and molybdenite, so it shows higher hydrophobicity and better flotability. Therefore, TGA is an effective inhibitor in the separation.Qin Wenqing Wu Jiajia Jiao Fen Zeng Jinming 2017International Journal of Mining Science and Technology2017,27,6:5
6Progress in improving thermodynamics and kinetics of new hydrogen storage materials显示文摘Li-fang SONG Chun-hong JIANG Shu-sheng LIU Cheng-li JIAO Xiao-liang SI Shuang WANG Fen LI Jian ZHANG Li-xian SUN Fen XU Feng-lei HUANG 2011Frontiers of physics2011,6,2:3
7Epigenetics: major regulators of embryonic neurogenesis显示文摘Mammalian cortical development is a dynamically and strictly regulated process orchestrated by extracellular signals and intracellular mechanisms. Recent studies show that epigenetic regulation serves as, at least in part, interfaces between genes and the environment, and also provides insight into the molecular and cellular bases of early embryonic cortical development. It is becoming increasingly clear that epigenetic regulation of cortical development occurs at multiple levels and that comprehensive knowledge of this complex regulatory landscape is essential to delineating embryonic neurogenesis.Tianjin Shen Fen Ji Jianwei Jiao 2015Science Bulletin2015,60,20:2
8Selective flotation of chalcopyrite and marmatite by MBT and electrochemical analysis 显示文摘QIN Wen-qing JIAO Fen SUN Wei et a l 2012Industrial and Engineering Chemistry Research2012,51,11:1
9Selective flotation of chalcopyrite and marmatite by MBT and electrochemical analysis 显示文摘QIN Wen-qing JIAO Fen SUN Wei HE Ming-fei HUANG Hong-jun 2012Ind Eng Chern Res2012,51,11:1
10Application of EDTMPS as a novel calcite depressant in scheelite flotation显示文摘In this study, the innovative use of ethylenediamine tetramethylene phosphonic sodium(EDTMPS) as a calcite depressant in scheelite flotation was investigated by flotation experiments, and its selective depression mechanism was revealed by contact angle measurement, FTIR analysis, Zeta potential test and XPS analysis. The flotation experiment results showed that scheelite and calcite could be efficiently separated under the following conditions: pulp p H=9.5, Na OL concentration of 1.5×10^(-4)mol/L, EDTMPS concentration of 3.0×10^(-5)mol/L, a scheelite concentrate with WO3grade of 65.49%, recovery of 83.29%and separation efficiency of 65.29% could be obtained from the artificially mixed minerals. The analysis results of mineral surface properties demonstrated that EDTMPS was strongly adsorbed onto the calcite surface through the reaction between the phosphonate group and the calcium ions, which hindered Na OL adsorption and increased the hydrophilicity of calcite. However, EDTMPS had weak adsorption strength on the scheelite surface, which didn’t affect further adsorption of Na OL, hence, the scheelite remained hydrophobic. Consequently, the selective adsorption of EDTMPS on the two minerals’ surfaces increased a difference in wettability and thus enabling them to be separated by flotation. Finally, the mechanism model of this flotation separation process was established.Fen Jiao Wei Li Xu Wang Congren Yang Zhengquan Zhang Liwen Fu Wenqing Qin 2023International Journal of Mining Science and Technology2023,33,5:1
11Selective flotation of chalcopyrite and marmatite by MBT and electrochemical analysis 显示文摘Qin Wenqing Jiao Fen Sun Wei 2012Industrial & Engineering Chemistry Re- search2012,51,11:1
12Effect of depressants on flotation separation of magnesite from dolomite and calcite显示文摘The flotation separation of magnesite from calcium-containing minerals has always been a difficult subject in minerals processing.This work studied the inhibition effects of carboxymethyl cellulose(CMC),sodium lignosulphonate,polyaspartic acid(PASP)and sodium silicate on flotation behaviors of magnesite,dolomite and calcite,providing guidance for the development of reagents in magnesite flotation.The micro-flotation results showed that among these four depressants,sodium silicate presented the strongest selectivity due to the highest recovery difference,and the flotation separation of magnesite from dolomite and calcite could be achieved by using sodium silicate as the depressant.Contact angle measurement indicated that the addition of sodium silicate caused the largest differences in surface wettability of the three minerals,which was in line with micro-flotation tests.Furthermore,zeta potential test,the Fourier transform infrared(FT-IR)spectroscopy and atomic force microscope(AFM)imaging were used to reveal the inhibition mechanism of sodium silicate.The results indicated that the dominated component SiO(OH)3of sodium silicate could adsorb on minerals surfaces,and the adsorption of sodium silicate hardly affected the adsorption of NaOL on magnesite surface,but caused the reduction of NaOL adsorption on dolomite and calcite surfaces,thereby increasing the flotation selectivity.Wenqing Qin Junjie Hu Hailing Zhu Fen Jiao Wenhao Jia Junwei Han Chen Chen 2023International Journal of Mining Science and Technology2023,33,1:1
13Alkyl dimethyl betaine activates the low-temperature collection capacity of sodium oleate for scheelite显示文摘The impact of alkyl dimethyl betaine (ADB) on the collection capacity of sodium oleate (NaOl) at low temperatures was evaluated using flotation tests at various scales. The low-temperature synergistic mechanism of ADB and NaOl was explored by infrared spectroscopy, X-ray photoelectron spectroscopy, surface tension measurement, foam performance test, and flotation reagent size measurement.The flotation tests revealed that the collector mixed with octadecyl dimethyl betaine (ODB) and NaOl in a mass ratio of 4:96 exhibited the highest collection capacity. The combined collector could increase the scheelite recovery by 3.48% at low temperatures of 8–12℃. This is particularly relevant in the Luanchuan area, which has the largest scheelite concentrate output in China. The results confirmed that ODB enhanced the collection capability of NaOl by improving the dispersion and foaming performance. Betaine can be introduced as an additive to NaOl to improve the recovery of scheelite at low temperatures.Xu Wang Zhengquan Zhang Yanfang Cui Wei Li Congren Yang Hao Song Wenqing Qin Fen Jiao 2024International Journal of Minerals,Metallurgy and Materials2024,31,1:0
14EVIDENCE FOR THE NOVEL COORDINATION MODE OF TERMINAL GROUP OF SOME TAILED PORPHYRIN IRON(Ⅱ)COMPLEXES显示文摘EVIDENCEFORTHENOVELCOORDINATIONMODEOFTERMINALGROUPOFSOMETAILEDPORPHYRINIRON(Ⅱ)COMPLEXES¥XiangDongJIAO;JinWangHUANG;JunFenLIU;...Xiang Dong JIAO Jin Wang HUANG Jun Fen LIU Ling Nian JI(Department of Chemistry, Zhongshan Univeristy,,Guangzhou,510275/National KeyLaboratory of Applied Organic Chemistry at Lanzhou University,Lanzhou,730000) 1994Chinese Chemical Letters1994,5,7:0
15Identification of Dominant Climate Variables on Spatiotemporal Variation in Reference Evapotranspiration on the Loess Plateau,China显示文摘Reference evapotranspiration(ET_(0))is a vital component in hydrometeorological research and is widely applied to various aspects,such as water resource management,hydrological modeling,irrigation deployment,and understanding and predicting the influence of hydrologic cycle variations on future climate and land use changes.Quantifying the influence of various meteorological variables on ET_(0) is not only helpful for predicting actual evapotranspiration but also has important implications for understanding the impact of global climate change on regional water resources.Based on daily data from 69 meteorological stations,the present study analyzed the spatiotemporal pattern of ET_(0) and major contributing meteorological variables to ET_(0) from 1960 to 2017 by the segmented re-gression model,Mann-Kendall test,wavelet analysis,generalized linear model,and detrending method.The results showed that the annual ET_(0) declined slightly because of the combined effects of the reduction in solar radiation and wind speed and the increase in vapor pressure deficit(VPD)and average air temperature in the Loess Plateau(LP)during the past 58 yr.Four change points were detected in 1972,1990,1999,and 2010,and the annual ET_(0) showed a zigzag change trend of‘increasing-decreasing-increasing-decreasing-increasing’.Wind speed and VPD played a leading role in the ET_(0) changes from 1960 to 1990 and from 1991 to 2017,respectively.This study confirms that the dominant meteorological factors affecting ET_(0) had undergone significant changes due to global climate change and vegetation greening in the past 58 years,and VPD had become the major factor controlling the ET_(0) changes on the LP.The data presented herein will contribute to increasing the accuracy of predictions on future changes in ET_(0).LI Xiaofei LIANG Wei JIAO Lei YAN Jianwu ZHANG Weibin WANG Fengjiao GOU Fen WANG Chengxi SHAO Quanqin 2022Chinese Geographical Science2022,32,4:0
16Comparative Metabolomics Analysis between Red- and White-Flowered Common Buckwheat Cultivars显示文摘Common buckwheat(Fagopyrum esculentum),a specialty crop in southwest China,is not only used as a supplement to primary grain crops but also to produce beverages,such as tea and wine.To fully exploit the products made from common buckwheat flower,ultra-performance liquid chromatography–electrospray ionization–tandem mass spectrometry(UPLC–ESI–MS/MS)was conducted to analyze the metabolites in red-(‘Guihong 2’)and white-flowered(‘Fengtian 1’)buckwheat cultivars.A total of 784 metabolites were identified of which flavonoids were the largest group with 191 components,followed by organic acids and derivatives(126),and amino acids and derivatives(95).Besides,dozens of phenylpropanoids,nucleotides and derivates,lipids,alkaloids as well as several kinds of indole derivatives and sterides were detected.Among these rich varieties of metabolites,24 metabolites were only detected in the red flower that mainly included 8 anthocyanins and 6 flavones,while 22 metabolites were only detected in the white flower,which mainly contained 5 lipids,5 flavonoids,and 5 organic acids and derivatives.Our results enrich the metabolites’information of buckwheat and may be helpful for the exploitation of products from common buckwheat flowers.Jiao Deng Fen Dong Chaoxin Wu Jiali Zhao Hongyou Li Juan Huang Taoxiong Shi Ziye Meng Fang Cai Qingfu Chen Pingfang Yang 2021Phyton-International Journal of Experimental Botany2021,90,3:0
17Expert consensus on blood pressure management in critically ill patients显示文摘Introduction For critically ill patients with unstable hemodynamics,goal‑directed therapy for arterial blood pressure is needed with continuous daily bedside monitoring.The prevalence of hypertension in Chinese adults is 25.2%,of which 1–2%of patients may experience a hypertensive emergency,with a mortality rate of 6.9%in the acute phase.The mortality and readmission rates within 90 days of onset are as high as 11%.[1]Furthermore,the mortality rate for patients who experience hypertensive emergencies can reach 50%within 12 months of the incident.[2]The incidence of perioperative hypertension in patients undergoing cardiac surgery is approximately 50%,with this figure dropping to 25%for non-cardiac surgery.Surgery may increase the incidence of perioperative cardio-cerebrovascular adverse events by 3–5%.[3]Yuetian Yu Ye Gong Bo Hu Bin Ouyang Aijun Pan Jinglun Liu Fen Liu Xiu-Ling Shang Xiang-Hong Yang Guowei Tu Changsong Wang Shaolin Ma Wei Fang Ling Liu Jiao Liu Dechang Chen 2023Journal of Intensive Medicine2023,3,3:0
18The transcription factor CsS40 negatively regulates TCS1 expression and caffeine biosynthesis in connection to leaf senescence in Camellia sinensis显示文摘Caffeine is considered as one of the most important bioactive components in the popular plant beverages tea,cacao,and coffee,but as a wide-spread plant secondary metabolite its biosynthetic regulation at transcription level remains largely unclear.Here,we report a novel transcription factor Camellia sinensis Senescnece 40(CsS40)as a caffeine biosynthesis regulator,which was discovered during screening a yeast expression library constructed from tea leaf cDNAs for activation of tea caffeine synthase(TCS1)promoter.Besides multiple hits of the non-self-activation CsS40 clones that bound to and activated TCS1 promoter in yeast-one-hybrid assays,a split-luciferase complementation assay demonstrated that CsS40 acts as a transcription factor to activate the CsTCS1 gene and EMSA assay also demonstrated that CsS40 bound to the TCS1 gene promoter.Consistently,immunofluorescence data indicated that CsS40-GFP fusion was localized in the nuclei of tobacco epidermal cells.The expression pattern of CsS40 in‘Fuding Dabai’developing leaves was opposite to that of TCS1;and knockdown and overexpression of CsS40 in tea leaf calli significantly increased and decreased TCS1 expression levels,respectively.The expression levels of CsS40 were also negatively correlated to caffeine accumulation in developing leaves and transgenic calli of‘Fuding Dabai’.Furthermore,overexpression of CsS40 reduced the accumulation of xanthine and hypoxanthine in tobacco plants,meanwhile,increased their susceptibility to aging.CsS40 expression in tea leaves was also induced by senescence-promoting hormones and environmental factors.Taken together,we showed that a novel senescence-related factor CsS40 negatively regulates TCS1 and represses caffeine accumulation in tea cultivar‘Fuding Dabai’.The study provides new insights into caffeine biosynthesis regulation by a plant-specific senescence regulator in tea plants in connection to leaf senescence and hormone signaling.Xinzhuan Yao Hufang Chen Antao Ai Fen Wang Shanshan Lian Hu Tang Yihe Jiang Yujie Jiao Yumei He Tong Li Litang Lu 2023Horticulture Research2023,10,9:0
19INTRAMOLECULAR β-CARBOXYLIC ACTIVATING OF N-PHOSPHORYL ASPARTIC ACID显示文摘The β-carboxylic group plays an important role inthe peptide formation,esterification and the ester exchangeat the phosphoryl group of N-phosphorylated aspartic acid.Yan Mei LI De Qing ZHANG Hong Wei ZHANG Gai Jiao JI Yu Fen ZHAODepartment of Chemistry,Tsinghua University,Beijing 100084Institute of Chemistry,Academia Sinica,Beijing 100080 1992Chinese Chemical Letters1992,3,5:0
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