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Measurements of Sulfur Isotope Composition on Ultrasmall(80 Nanomole) Sulfide and Sulfate Samples by a Modified EA-IRMS

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Acta Geologica Sinica(English Edition) 2022年第5期96卷 1792-1799页

作者： WU Xiaopei FAN Changfu HU Bin gao jianfei LI Yanhe MNR Key Laboratory of Metallogeny and Resource Assessment Institute of Mineral ResourcesCAGSBeijing 100037China School of Earth and Space Sciences Peking UniversityBeijing 100871China

The traditional method for sulfur isotope measurement using EA-IRMS commonly requires sulfur content greater than 2 μmol. Such a large sample size limits its application to low-S materials, the size mainly being due to ineffective utilization of sample gas, almost 99.7% of which is discarded with carrier gas through the split port of the continuous-flow interface. A modified EA-IRMS system with a gas chromatographic(GC) column and a custom-built cryogenic concentration device is used in this study. We measured six reference materials to test the performance of this method. The results were consistent with those obtained through traditional EA-IRMS. Precisions ranging from ±0.24‰ to ±0.76‰(1σ)can be obtained with samples equivalent to ~80 nmol sulfur, which were similar to results obtained from an alternative method using an absorption column. Our improved method is a powerful tool for sulfur isotope measurement in ultrasmall sulfide and sulfate samples, which can be further applied to carbon, nitrogen and oxygen isotope analyses of samples at about 100 nmol level.

关键词： sulfur isotopes ultrasmall sample cryogenic concentration EA-IRMS

Differential metabolome landscape of Kadsura coccinea fruit tissues and potential valorization of the peel and seed tissues

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BIOCELL 2022年第1期46卷 285-296页

作者： jianfei gao KANGNING XIONG WEIJIE LI WEI ZHOU Institute of Mountain Resources Guizhou Academy of SciencesGuiyang550001China School of Karst Science Guizhou Normal UniversityState Engineering Technology Institute for Karst Desertfication Control of ChinaGuiyang550001China Guizhou Industry Polytechnic College Guiyang550008China

Kadsura coccinea(Lem.)is a woody wine plant with a peculiar fruit enriched in important health-promoting *** non-editable part of the fruit,i.e.,the seed and peel,represents more than 60%of the fruit and is considered a *** significantly restricts the development of the *** fruit *** the metabolic components of the different fruit parts can help to improve the utilization rate and valorization of ***,we evaluated *** fruit peel,pulp,and seed using widely-targeted metabolomics and quantified a set of 736 bioactive compounds from 11 major metabolite *** most prominent metabolite classes included lipids,amino acids,flavonoids,and ***,our results emphasized a significant accumulation of flavonoids in pulp tissues,while alkaloids and lignans were abundant in peel and seed tissues,respectively.A total of 183 metabolites were differentially accumulated among the three *** C2,rutinoside,2-hydroxyoleanolic acid,5-hydroxymethyluracil,nootkatol,isoquercitrin,isohyperoside,quercetin-7-O-glucoside,hyperin,and rutin showed elevated accumulation in the *** the seed,kadsuralignan G,kadcoccilactone A,kadsuralignan H,lysoPE 20:5,iso-schisandrin ethyl alcohol,and kadangustin were significantly *** results highlight the diverse metabolome composition of *** fruit parts,which can be further exploited for its valorization in various industries.

关键词： Kadsura coccinea Widely-targeted metabolomics Alkaloids Lignans Flavonoids Fruit Biowaste valorization

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鲜切甘薯褐变机理及抑制技术研究进展

江苏师范大学学报（自然科学版） 2024年第3期42卷 35-38页

作者：程丽林高建菲李宗芸江苏师范大学生命科学学院江苏徐州221116 淮阴工学院生命科学与食品工程学院江苏淮安223001

甘薯在加工过程中受到机械损伤,易发生褐变,严重制约着甘薯加工产业的发展.对影响褐变的相关酶、酚类物质、膜脂过氧化等因素进行了梳理,综述了甘薯褐变机理研究现状,并介绍了国内外常用的物理和化学等褐变抑制技术.研究甘薯褐变机理并... 详细信息

甘薯在加工过程中受到机械损伤,易发生褐变,严重制约着甘薯加工产业的发展.对影响褐变的相关酶、酚类物质、膜脂过氧化等因素进行了梳理,综述了甘薯褐变机理研究现状,并介绍了国内外常用的物理和化学等褐变抑制技术.研究甘薯褐变机理并开展鲜切甘薯褐变抑制技术开发,对有效缓解甘薯褐变的发生,延长其货架期具有重要的作用;同时,褐变抑制技术也为甘薯加工中酶促褐变的调控提供参考,促进甘薯鲜食及加工制品的品质提升.

关键词：甘薯褐变机理抑制技术研究进展

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铁路客车单元式变频空调机组的研究及应用

铁道车辆 2024年第1期62卷 189-192页

作者：高健飞周剑峰薛宏佺中车南京浦镇车辆有限公司江苏南京210031

空调机组是通过调节客室温度提高列车舒适性的重要装置,也是列车能耗的主要部件之一。目前轨道车辆空调机组主要分为定频空调和变频空调2种;定频空调是根据客室内热负荷的需求,压缩机以固定转速运转,通过启停压缩机改变制冷量输出,实现... 详细信息

空调机组是通过调节客室温度提高列车舒适性的重要装置,也是列车能耗的主要部件之一。目前轨道车辆空调机组主要分为定频空调和变频空调2种;定频空调是根据客室内热负荷的需求,压缩机以固定转速运转,通过启停压缩机改变制冷量输出,实现客室温度调节;变频空调是根据客室内热负荷的需求,通过变频器控制压缩机的转速,提供线性可变制冷量输出,实现客室温度调节。文章分析了25G、25T型铁路普速客车空调的应用现状,详细介绍了铁路普速客车上定频空调改造成变频空调的技术方案以及验证情况,结果表明,变频空调技术提高了铁路普速客车的舒适性并且节能,优势明显,建议推广。

关键词：铁路客车变频空调技术改造节能舒适

Chemical and Isotopic Characteristics of the Water and Suspended Particulate Materials in the Yangtze River and Their Geological and Environmental Implications

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Acta Geologica Sinica(English Edition) 2014年第1期88卷 276-360页

作者： DING Tiping gao jianfei TIAN Shihong SHI Guoyu CHEN Feng WANG Chengyu LUO Xurong HAN Dan MLR Key Laboratory of Metallogeny and Mineral Assessment Institute of Mineral Resources CAGS Open Research Laboratory of Isotope Geology Hydrological Bureau CWRC

The chemical and isotopic characteristics of the water and suspended particulate materials（SPM） in the Yangtze River were investigated on the samples collected from 25 hydrological monitoring stations in the mainsteam and 13 hydrological monitoring stations in the major tributaries during 2003 to 2007. The water samples show a large variation in both δD（ 30‰ to 112‰） and δ18O（ 3.8‰ to 15.4‰） values. Both δD and δ18O values show a decrease from the river head to the Jinsha Jiang section and then increase downstream to the river mouth. It is found that the oxygen and hydrogen isotopic compositions of the Yangtze water are controlled by meteoric precipitation, evaporation, ice（and snow） melting and dam building. The Yangtze SPM concentrations show a large variation and are well corresponded to the spatial and temporal changes of flow speed, runoff and SPM supply, which are affected by the slope of the river bed, local precipitation rate, weathering intensity, erosion condition and anthropogenic activity. The Yangtze SPM consists of clay minerals, clastic silicate and carbonate minerals, heavy minerals, iron hydroxide and organic compounds. From the upper to lower reaches, the clay and clastic silicate components in SPM increase gradually, but the carbonate components decrease gradually, which may reflect changes of climate and weathering intensity in the drainage area. Compared to those of the upper crust rocks, the Yangtze SPM has lower contents of SiO2, CaO, K2 O and Na2 O and higher contents of TFe2 O3 and trace metals of Co, Ni, Cu, Zn, Pb and Cd. The ΣREE in the Yangtze SPM is also slightly higher than that of the upper crust. From the upper to lower reaches, the CaO and MgO contents in SPM decrease gradually, but the SiO2 content increases gradually, corresponding to the increase of clay minerals and decrease of the carbonates. The δ30SiSPM values（ 1.1‰ to 0.3‰） of the Yangtze SPM are similar to those of the average shale, but lower than those of the granite rock

关键词： Yangtze River stable isotopes water chemistry Suspended Particulate Materials(SPM) hydrology environmental implication

Chemical and Isotopic Characters of the Water and Suspended Particulate Materials in the Yellow River and Their Geological and Environmental Implications

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Acta Geologica Sinica(English Edition) 2016年第1期90卷 285-351页

作者： DING Tiping gao jianfei TIAN Shihong WANG Huaibai LI Ming WANG Chengyu LUO Xurong HANG Dan MLR Key Laboratory of Metallogeny and Mineral Assessment Institute of Mineral ResourcesCAGSBeijing 100037China MLR Key Laboratory of Isotope Geology CAGSBeijing 100037China Hydrological Bureau YRCCZhengzhou 450004China

The chemical and isotopic characteristics of the water and suspended particulate materials （SPM） in the Yellow River were investigated on the samples collected from 29 hydrological monitoring stations in the mainstem and several major tributaries during 2004 to 2007. The JD and δ^18O values of the Yellow River water vary in large ranges from -32%0 to -91‰ and from -3.1‰ to -12.5‰, respectively. The characters of H and O isotope variations indicate that the major sources of the Yellow River water are meteoric water and snow melting water, and water cycle in the Yellow River basin is affected strongly by evaporation process and human activity. The average SPM content （9.635 g/L） of the Yellow River is the highest among the world large rivers. Compared with the Yangtze River, the Yellow River SPM has much lower clay content and significantly higher contents of clastic silicates and carbonates. In comparison to the upper crust rocks, the Yellow River SPM contains less SiO2, CaO, K2O and Na2O, but more TFe203, Co, Ni, Cu, Zn, Pb and Cd. The abnormal high Cd contents found in some sample may be related to local industrial activity. The REE contents and distribution pattern of the Yellow River SPM are very close to the average value of the global shale. The average δ^30Sisp in the Yellow River （-0.11‰） is slightly higher than the average value （-0.22‰） of the Yangtze River SPM. The major factors controlling the δ^30Si SPM of the Yellow River are the soil supply, the isotopic composition of the soil and the climate conditions. The TDS in the Yellow River are the highest among those of world large rivers. Fair correlations are observed among Cl, Na^＋, K^＋, and Mg^2＋ contents of the Yellow River water, indicating the effect of evaporation. The Ca^2＋ and Sr^2＋ concentrations show good correlation to the SO42 concentration rather than HCO3-concentration, reflecting its origin from evaporates. The NO3-contents are affected by farmland fertilization. The Cu, Zn and Cd contents in

关键词： Yellow River stable isotopes water chemistry suspended particulate materials (SPM) hydrology environmental implication

Cisplatin sensitivity and mechanisms of anti-HPV16 E6-ribozyme on cervical carcinoma CaSKi cell line

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The Chinese-German Journal of Clinical Oncology 2012年第4期11卷 237-242页

作者： Zhiguo Rao jianfei gao Bicheng Zhang Bo Yang Jiren Zhang Department of Oncology Wuhan General Hospital of Guangzhou Command Wuhan 430070 China Oncology Center Zhujiang Hospital Southern Medical University Guangzhou 510280 China

Objective： The aim of this study was to study the cisplatin sensitizing effect and mechanism of anti-HPV16 E6- ribozyme on cervical carcinoma cell line. Methods： The anti-HPV16E6-ribozyme and empty eucaryotic expressing plasmids were transfected into CaSKi cell, which named as CaSKi-R, CaSKi-P respectively. E6 mRNA, the sensitivity to cisplatin, apoptosis rates, expression of p53, Bcl-2, Bax and C-myc proteins and mRNA were examined by Northem blot, MTT colorimetric assay, PI/Annexin V stained methods, flow cytometry anslysis and RT-PCR, respectively. Results： E6 mRNA was less in CaSKi-R than in CaSKi. The sensitivity of CaSKi-R cells to cisplatin was 2.28 and 2.21 times than that of CaSKi and CaSKi-P cells. The apoptotic rates in CaSKi, CaSKi-P and CaSKi-R cells was （18.9 ± 3.5）%, （19.7 ± 4.8）% and （40.4 ± 4.5）%. The apoptotic rates was increased in CaSKi-R than that of CaSKi cells treated with cisplatin （P = 0.003）. Comapred with CaSKi cell, the expression of p53 （P = 0.000）, Bax protein （P = 0.002） was significantly higher and the expression of Bcl-2 protein （P = 0.005）, C-myc protein （P = 0.005） was significantly lower in CaSKi-R than that of CaSKi cell treated with cisplatin. Comapred with CaSKi cell, the expression of p53, Bax mRNA in CaSKi-R cell treated with cisplatin increased, while Bcl-2, C-myc mRNA decreased. Conclusion： CaSKi-R cells transfected by anti-HPVE6-ribozyme increased the sensitivity to cisplatin. The increase of sensitivity to cisplatin in CaSKi-R cells may be associated with increasing expression of p53, Bax protein, and decreasing expression of C-myc, Bcl-2 proteins.

关键词： ribozyme human papillomavirus cisplatin drug sensitivity cervical cancer

Interorgan communication in neurogenic heterotopic ossification: the role of brain-derived extracellular vesicles

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Bone Research 2024年第1期12卷 137-152页

作者： Weicheng Lu jianfei Yan Chenyu Wang Wenpin Qin Xiaoxiao Han Zixuan Qin Yu Wei Haoqing Xu Jialu gao Changhe gao Tao Ye Franklin R.Tay Lina Niu Kai Jiao Department of Stomatology Tangdu Hospital&State Key Laboratory of Oral and Maxillofacial Reconstruction and Regeneration&School of StomatologyThe Fourth Military Medical UniversityXi’anShaanxiChina State Key Laboratory of Oral and Maxillofacial Reconstruction and Regeneration&National Clinical Research Center for Oral Diseases&Shaanxi Key Laboratory of Stomatology School of StomatologyThe Fourth Military Medical UniversityXi’anShaanxiChina The Dental College of Georgia Augusta UniversityAugustaGAUSA

Brain-derived extracellular vesicles participate in interorgan communication after traumatic brain injury by transporting pathogens to initiate secondary ***-related proteins encapsulated in brain-derived extracellular vesicles can cross the blood‒brain barrier to reach distal *** proteins initiate inflammatory dysfunction,such as neurogenic heterotopic *** recurrent condition is highly debilitating to patients because of its relatively unknown pathogenesis and the lack of effective prophylactic intervention ***,a rat model of neurogenic heterotopic ossification induced by combined traumatic brain injury and achillotenotomy was developed to address these two *** examination of the injured tendon revealed the coexistence of ectopic calcification and fibroblast *** relationships among brain-derived extracellular vesicles,fibroblast pyroptosis and ectopic calcification were further investigated in vitro and in *** injection of the pyroptosis inhibitor Ac-YVAD-cmk reversed the development of neurogenic heterotopic ossification in *** present work highlights the role of brain-derived extracellular vesicles in the pathogenesis of neurogenic heterotopic ossification and offers a potential strategy for preventing neurogenic heterotopic ossification after traumatic brain injury.

关键词： neurogenic ossification pathogenesis

Efficient hydrogen production from high-concentration aqueous formic acid over bio-basedγ-Mo_(2)N catalysts

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Carbon Resources Conversion 2024年第3期7卷 8-16页

作者： Zeyu Liu Song Yang Yanyan Yang Wenyao Guo jianfei Wang Bixi Wang Xin gao Ting Wang Shoujun Liu Zhongliang Yu College of Chemistry Taiyuan University of TechnologyTaiyuan 030024China School of Chemistry and Environmental Science Shangrao Normal UniversityShangrao 334001China Engineering Center of Civil Clean Fuel Taiyuan 030024China College of Chemical Engineering and Technology Taiyuan University of TechnologyTaiyuan 030024China School of Chemistry and Chemical Engineering Kunming UniversityKunming 650214China

Formic acid is regarded to be one of the most prospective hydrogen *** screening of the fitting non-noble-metal-based heterogeneous catalysts to substitute the expensive noble-metal-based ones for FA dehydrogenation is considered as a key to the commercial application for hydrogen ***,dehydrogenation of liquid neat FA achieved a gas production value of 1753.5 mL/gcat./h at 94℃by using a biomass-derivedγ-Mo_(2)N based catalyst synthesized from the earth-abundant molybdenum and soybean with a facile pyrolysis *** effect of material ratio,pyrolysis temperature on the catalytic performance of FA dehydrogenation were studied in *** particular,the catalyst obtained at a pyrolysis temperature of 700℃,weight ratios of ammonium molybdate to soybean of 0.2/1 exhibited the highest *** addition,the catalytic activity increased with the increase of FA concentration,but conversely,the dehydrogenation selectivity decreased with the increasing FA ***,it was found that the Bio-Mo_(2)N catalyst was rather stable over the 40 h continuous reaction period.

关键词： Formic acid Non-noble-metal catalyst Dehydrogenation Hydrogen Molybdenum nitride