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Preferentially selective extraction of lithium from spent LiCoO_(2)cathodes by medium-temperature carbon reduction roasting 被引量:1
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作者 Daixiang Wei Wei Wang +6 位作者 Longjin Jiang Zhidong Chang Hualei Zhou Bin Dong Dekun Gao Minghui Zhang Chaofan Wu 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2024年第2期315-322,共8页
Lithium recovery from spent lithium-ion batteries(LIBs)have attracted extensive attention due to the skyrocketing price of lithium.The medium-temperature carbon reduction roasting was proposed to preferential selectiv... Lithium recovery from spent lithium-ion batteries(LIBs)have attracted extensive attention due to the skyrocketing price of lithium.The medium-temperature carbon reduction roasting was proposed to preferential selective extraction of lithium from spent Li-CoO_(2)(LCO)cathodes to overcome the incomplete recovery and loss of lithium during the recycling process.The LCO layered structure was destroyed and lithium was completely converted into water-soluble Li2CO_(3)under a suitable temperature to control the reduced state of the cobalt oxide.The Co metal agglomerates generated during medium-temperature carbon reduction roasting were broken by wet grinding and ultrasonic crushing to release the entrained lithium.The results showed that 99.10%of the whole lithium could be recovered as Li2CO_(3)with a purity of 99.55%.This work provided a new perspective on the preferentially selective extraction of lithium from spent lithium batteries. 展开更多
关键词 spent LiCoO_(2)cathodes medium-temperature carbon reduction lithium extraction priority crystal transformation macro-scopic transport resistance
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Evaluation of the intracellular lipid-lowering effect of polyphenols extract from highland barley in HepG2 cells 被引量:2
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作者 Yijun Yao Zhifang Li +2 位作者 Bowen Qin Xingrong Ju Lifeng Wang 《Food Science and Human Wellness》 SCIE CSCD 2024年第1期454-461,共8页
Active ingredients from highland barley have received considerable attention as natural products for developing treatments and dietary supplements against obesity.In practical application,the research of food combinat... Active ingredients from highland barley have received considerable attention as natural products for developing treatments and dietary supplements against obesity.In practical application,the research of food combinations is more significant than a specific food component.This study investigated the lipid-lowering effect of highland barley polyphenols via lipase assay in vitro and HepG2 cells induced by oleic acid(OA).Five indexes,triglyceride(TG),total cholesterol(T-CHO),low density lipoprotein-cholesterol(LDL-C),aspartate aminotransferase(AST),and alanine aminotransferase(ALT),were used to evaluate the lipidlowering effect of highland barley extract.We also preliminary studied the lipid-lowering mechanism by Realtime fluorescent quantitative polymerase chain reaction(q PCR).The results indicated that highland barley extract contains many components with lipid-lowering effects,such as hyperoside and scoparone.In vitro,the lipase assay showed an 18.4%lipase inhibition rate when the additive contents of highland barley extract were 100μg/m L.The intracellular lipid-lowering effect of highland barley extract was examined using 0.25 mmol/L OA-induced HepG2 cells.The results showed that intracellular TG,LDL-C,and T-CHO content decreased by 34.4%,51.2%,and 18.4%,respectively.ALT and AST decreased by 51.6%and 20.7%compared with the untreated hyperlipidemic HepG2 cells.q PCR results showed that highland barley polyphenols could up-regulation the expression of lipid metabolism-related genes such as PPARγand Fabp4. 展开更多
关键词 Highland barley Polyphenols extract Lipid-lowering effect HepG2 cells
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Joint Biomedical Entity and Relation Extraction Based on Multi-Granularity Convolutional Tokens Pairs of Labeling
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作者 Zhaojie Sun Linlin Xing +2 位作者 Longbo Zhang Hongzhen Cai Maozu Guo 《Computers, Materials & Continua》 SCIE EI 2024年第9期4325-4340,共16页
Extracting valuable information frombiomedical texts is one of the current research hotspots of concern to a wide range of scholars.The biomedical corpus contains numerous complex long sentences and overlapping relati... Extracting valuable information frombiomedical texts is one of the current research hotspots of concern to a wide range of scholars.The biomedical corpus contains numerous complex long sentences and overlapping relational triples,making most generalized domain joint modeling methods difficult to apply effectively in this field.For a complex semantic environment in biomedical texts,in this paper,we propose a novel perspective to perform joint entity and relation extraction;existing studies divide the relation triples into several steps or modules.However,the three elements in the relation triples are interdependent and inseparable,so we regard joint extraction as a tripartite classification problem.At the same time,fromthe perspective of triple classification,we design amulti-granularity 2D convolution to refine the word pair table and better utilize the dependencies between biomedical word pairs.Finally,we use a biaffine predictor to assist in predicting the labels of word pairs for relation extraction.Our model(MCTPL)Multi-granularity Convolutional Tokens Pairs of Labeling better utilizes the elements of triples and improves the ability to extract overlapping triples compared to previous approaches.Finally,we evaluated our model on two publicly accessible datasets.The experimental results show that our model’s ability to extract relation triples on the CPI dataset improves the F1 score by 2.34%compared to the current optimal model.On the DDI dataset,the F1 value improves the F1 value by 1.68%compared to the current optimal model.Our model achieved state-of-the-art performance compared to other baseline models in biomedical text entity relation extraction. 展开更多
关键词 Deep learning BIOMEDICAL joint extraction triple classification multi-granularity 2D convolution
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Intensified reactive extraction of 4-hydroxypyridine with di(2-ethylhexyl) phosphoric acid in 1-octanol by using tributyl phosphate
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作者 Zhixian Chang Xiangfeng Zhou +2 位作者 Huihua Bai Deliang Li Ling Zhang 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2023年第2期199-205,共7页
The efficient separation of amphoteric organic compounds from dilute solutions is of great importance in the industrial field. In the present work, the reactive extractions of 4-hydroxypyridine(4-HP) with tributyl pho... The efficient separation of amphoteric organic compounds from dilute solutions is of great importance in the industrial field. In the present work, the reactive extractions of 4-hydroxypyridine(4-HP) with tributyl phosphate(TBP), di(2-ethylhexyl) phosphoric acid(D2EHPA) and TBP + D2EHPA dissolved in 1-octanol were investigated, respectively. The influences of the initial concentrations of TBP, D2EHPA and TBP + D2EHPA on distribution ratio(D) were discussed, as well as the reactive extraction mechanism were proposed. The obvious intensification effect was observed when the mixture of TBP and D2EHPA was used as extractant. The best extraction conditions were found to be of the molar ratio of D2EHPA and TBP at 2:1 and the equilibrium aqueous pH at 3.50-4.50. D values increased with the increase of the total concentration of TBP and D2EHPA in 1-octanol. Especially, the analysis on the extraction mechanisms clearly indicate(i) TBP in 1-octanol shows negligible reactive extraction toward 4-HP,(ii) D2EHPA in 1-octanol exhibits moderate extraction effect by forming 4-HP:D2EHPA(1:1) and 4-HP:2D2EHPA(1:2) type complexes, while(iii) D2EHPA in TBP/1-octanol demonstrates the maximum distribution ratio with the 4-HP:D2EHPA(1:1) type complex domination. The discussion provides new insights on the mechanism and opens a new way for the intensified extraction of amphoteric organic compounds by using the mixture of multiple extractants in the diluent. 展开更多
关键词 4-Hydroxypyridine Di(2-ethylhexyl)phosphoric acid Tributyl phosphate Reactive extraction Intensified extraction
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Adenosine cyclic phosphate with ultrasonic-assisted pectinase extraction alleviated allergic reactions in RBL-2H3 through inhibiting the influx of intracellular Ca^(2+)
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作者 Qiao Bai Xiaoping Feng +5 位作者 Yu Wang Chunyu Wu Ye Liu Jiao Sun Tianli Yue Fangyu Long 《Food Science and Human Wellness》 SCIE CSCD 2023年第3期832-841,共10页
Jujube contains abundant cyclic adenosine monophosphate(cAMP)and the ultrasonic-assisted pectinase extraction(UAPE)conditions for obtaining the maximum cAMP yield from jujube were optimized.Orthogonal array design was... Jujube contains abundant cyclic adenosine monophosphate(cAMP)and the ultrasonic-assisted pectinase extraction(UAPE)conditions for obtaining the maximum cAMP yield from jujube were optimized.Orthogonal array design was applied to evaluate the effects of 4 variables by UAPE on cAMP yield.The results showed that the optimal cAMP yield(783.0μg/g)was derived at ratio of liquid to solid 5 mL/g,ratio of pectinase to raw material 1.5%,time 60 min and temperature 40℃.Moreover,the effect of cAMP on the anti-allergic function of action induced by immunoglobulin E(IgE)and its meschanism was investigated through establishing the sensitized cell model in rat basophilic leukemia(RBL-2 H3)cells using dinitrophenylated(DNP)-bovine serum albumin(BSA)-IgE.The results showed that cAMP interfered with sensitized cells,effectively inhibited the occurrence of basophil degranulation in dose dependence,and significantly reduced the activity ofβ-hexosamindase(β-hex),at the optimal concentration of 50μg/mL.The level of anti-inflammatory factor interleukin-10(IL-10)was promoted and the content of pro-inflammatory factor tumor necrosis factor-α(TNF-α)was suppressed by cAMP.In addition,influx of intracellular Ca^(2+) was repressed effectively.Our results demonstrate that jujube cAMP regulated the cytokine balance in the allergy pathway through blocking the influx of extracellular Ca^(2+),with the prevention of allergy symptoms. 展开更多
关键词 Ultrasonic-assisted pectinase extraction Cyclic adenosine monophosphate Rat basophilic leukemia cells Ca^(2+)influx Allergy
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Thermodynamics and mechanism of vanadium(IV) extraction from sulphate medium with D2EHPA,EHEHPA and CYANEX 272 in kerosene 被引量:13
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作者 李兴彬 魏昶 +4 位作者 吴钧 李存兄 李旻廷 邓志敢 徐红胜 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2012年第2期461-466,共6页
Extraction of vanadium(IV) from sulphate acid solution was studied using organophosphorous-based extractants D2EHPA, EHEHPA and CYANEX 272 in kerosene. The different parameters affecting the extraction of vanadium... Extraction of vanadium(IV) from sulphate acid solution was studied using organophosphorous-based extractants D2EHPA, EHEHPA and CYANEX 272 in kerosene. The different parameters affecting the extraction of vanadium(IV) under equilibrium conditions were separately investigated to elucidate the stoichiometry of the extracted species. The distribution ratio of vanadium increased with increasing equilibrium pH of the aqueous phase, concentration of the extractants and temperature. D2EHPA was found to be a stronger extractant, having greater pH functionality than EHEHPA and CYANEX 272. Extraction of vanadium(IV) by these organophosphorous-based extractants involved cation exchange mechanism, and the extracted species appear to be VOR2(HR)2 in the low equilibrium pH and VOR2 in the higher equilibrium pH, where HR refers to the three acidic extractants. 展开更多
关键词 VANADIUM solvent extraction D2EHPA EHEHPA CYANEX 272
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Effect of Allelochemicals of Chinese-fir root extracted by supercritical CO_2 extraction on Chinese fir 被引量:9
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作者 林思祖 曹光球 +1 位作者 杜玲 王爱萍 《Journal of Forestry Research》 SCIE CAS CSCD 2003年第2期122-126,共5页
Allelochemicals of Chinese-fir root was extracted by technology ofsupercritical CO_2 extraction under orthogonal experiment design, and it was used to analyzeallelopathic activity of Chinese-fir through bioassay of se... Allelochemicals of Chinese-fir root was extracted by technology ofsupercritical CO_2 extraction under orthogonal experiment design, and it was used to analyzeallelopathic activity of Chinese-fir through bioassay of seed germination. The results showed thatas to the available rate of allelochemicals, the pressure and temperature of extraction were themost important factors. The allelochemicals of Chinese-fir root extracted by pure CO_2 and ethanolmixed with CO_2 have different allelopathic activities to seed germination, and the allelochemicalsextracted by ethanol mixed with CO_2 had stronger inhibitory effects on seed germination than thatextracted by pure CO_2. 展开更多
关键词 chinese fir autointoxication supercritical CO_2 extraction BIOASSAY SEEDGERMINATION
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A Comparative Study on Chemical Composition of Supercritical CO_2 Extraction Products in Peels of Trichosanthes kirilowii Maxim. from Changqing District
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作者 于京平 李佳 +1 位作者 张永清 范英才 《Agricultural Science & Technology》 CAS 2013年第2期257-261,共5页
[Objective] This study aimed to investigate the differences in chemical composition of supercritical CO2 extraction products in peels of Trichosanthes kirilowii Maxim. from Changqing district. [Method] Supercritical f... [Objective] This study aimed to investigate the differences in chemical composition of supercritical CO2 extraction products in peels of Trichosanthes kirilowii Maxim. from Changqing district. [Method] Supercritical fluidextraction (SFE) and GCMS method were applied to determine and analyze the chemical components of the extracts in peels of three strains of Trichosanthes kirilowii Maxim. [Result] The chemical components of supercritical CO2 extraction products in peels of three strains of Trichosanthes kirilowii Maxim. varied., and the number of chemical components with normalized percentage content higher than 1% was 5, 7 and 8, respectively. There are 14 kinds of common components, and the relative content of hexadecanoic acid was the highest. [Conclusion] Supercritical CO2 extracts in peels of different strains of Trichosanthes kirilowii Maxim. contain different chemical components, providing scientific basis for breeding excellent varieties and the development and utilization of Trichosanthes kirilowii Maxim. 展开更多
关键词 Trichosanthes kirilowii Maxim. PEEL Supercritical CO2 extraction products Chemical components COMPARISON
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Effect of Allelochemicals of Chinese-fir root extracted by supercritical CO2 extraction on Chinese fir 被引量:5
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作者 林思祖 曹光球 +1 位作者 杜玲 王爱萍 《Journal of Forestry Research》 SCIE CAS CSCD 2003年第2期122-126,185-186,共页
Allelochemicals of Chinese-fir root was extracted by technology of supercritical CO2 extraction under orthogonal experiment design, and it was used to analyze allelopathic activity of Chinese-fir through bioassay of s... Allelochemicals of Chinese-fir root was extracted by technology of supercritical CO2 extraction under orthogonal experiment design, and it was used to analyze allelopathic activity of Chinese-fir through bioassay of seed germination. The results showed that as to the available rate of allelochemicals, the pressure and temperature of extraction were the most important factors. The allelochemicals of Chinese-fir root extracted by pure CO2 and ethanol mixed with CO2 have different allelopathic activities to seed germination, and the allelochemicals extracted by ethanol mixed with CO2 had stronger inhibitory effects on seed germination than that extracted by pure CO2. 展开更多
关键词 Chinese fir Autointoxication Supercritical CO2 extraction BIOASSAY Seed germination
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自激振荡脉冲SC-CO_(2)射流冲击频率调制
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作者 魏建平 李翔 +3 位作者 刘勇 沈荷莲 李海超 高梦雅 《煤炭学报》 EI CAS CSCD 北大核心 2024年第6期2675-2690,共16页
SC-CO_(2)射流钻完井技术能保证煤层气井稳定性、提高钻井速度和破岩效率,具有广泛的应用前景。但较高的破煤能耗和复杂的系统限制了其工程推广,自激振荡脉冲SC-CO_(2)射流冲击频率和煤岩体的固有频率相同或满足相位关系,能充分发挥谐... SC-CO_(2)射流钻完井技术能保证煤层气井稳定性、提高钻井速度和破岩效率,具有广泛的应用前景。但较高的破煤能耗和复杂的系统限制了其工程推广,自激振荡脉冲SC-CO_(2)射流冲击频率和煤岩体的固有频率相同或满足相位关系,能充分发挥谐振效应,达到更好的破煤效果。喷嘴结构是影响射流冲击频率的关键,现有的自振脉冲水射流频率调制方法并不适用于SC-CO_(2)射流。为实现对SC-CO_(2)射流冲击频率的调制,采用大涡模拟研究不同喷嘴结构对自激振荡脉冲SCCO_(2)射流冲击频率的影响规律,通过权重分析得到不同喷嘴结构参数对射流冲击频率的影响程度。采用射流冲击频率测定实验及破煤实验验证喷嘴结构对射流冲击频率的影响规律以及射流冲击频率调制方法的可靠性。结果表明:振荡腔直径、振荡腔长度、碰撞壁角度是影响射流冲击频率的关键因素,可通过调节振荡腔结构实现对射流冲击频率的大幅调制,从而达到谐振效应。调节振荡腔结构使射流冲击频率与煤的固有频率形成谐振时破煤效果显著提升,且谐振倍数越小,射流破煤效果越好,能够有效提高破煤效率。当煤的固有频率是25 Hz时,设置上游和下游喷嘴出口直径为2.5、3.0 mm,调节振荡腔直径、长度、角度分别为10 mm、3 mm、120°,射流冲击频率达到25051.83 Hz,是煤体固有频率的1002.0倍,与煤的固有频率形成谐振效应,有效提高了破煤效率。 展开更多
关键词 自激振荡脉冲SC-CO_(2)射流 自激振荡喷嘴 冲击频率调制 谐振破煤 煤层气开采
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酸枣仁油的超临界CO_(2)萃取工艺及其抗氧化性研究
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作者 李敏 周刚 +3 位作者 武丽娜 王僧虎 陈紫林 崔泽 《邢台学院学报》 2024年第3期155-160,共6页
采用超临界CO_(2)萃取技术对酸枣仁进行油脂萃取。利用单因素实验方法考查了孔径、萃取温度、萃取压力、萃取时间四个因素对酸枣仁出油率的影响,最佳萃取条件下对酸枣仁油脂样品进行GC-MS组分分析及DPPH清除能力测定。结果表明:超临界CO... 采用超临界CO_(2)萃取技术对酸枣仁进行油脂萃取。利用单因素实验方法考查了孔径、萃取温度、萃取压力、萃取时间四个因素对酸枣仁出油率的影响,最佳萃取条件下对酸枣仁油脂样品进行GC-MS组分分析及DPPH清除能力测定。结果表明:超临界CO_(2)萃取酸枣仁油的最佳工艺为过筛目数80目,温度为45℃,萃取压力40 MPa,时间30 min,在最佳萃取工艺条件下,出油率为29.40%。GC-MS检测结果表明酸枣仁油含有27种化合物,DPPH的清除率IC_(50)值为29.12 mg/mL。 展开更多
关键词 酸枣仁油 超临界CO_(2)萃取 工艺参数 抗氧化性
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古龙页岩油注CO_(2)/烃类气相态特征及多周期作用机制
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作者 宋兆杰 邓森 +5 位作者 韩啸 张翊航 张利超 李斌会 陈旻宸 李培宇 《重庆科技大学学报(自然科学版)》 CAS 2024年第4期1-10,共10页
基于PVT实验和多周期注CO_(2)/烃类气采油物理模拟实验,结合相态模拟计算揭示古龙页岩油注气前后的高压物性和流体类型演化规律,评价多周期注气作用下的原油采出效果,分析多组分间的抽提传质机理。实验结果表明:古龙页岩油属于轻质弱挥... 基于PVT实验和多周期注CO_(2)/烃类气采油物理模拟实验,结合相态模拟计算揭示古龙页岩油注气前后的高压物性和流体类型演化规律,评价多周期注气作用下的原油采出效果,分析多组分间的抽提传质机理。实验结果表明:古龙页岩油属于轻质弱挥发性油藏,当压力降低至泡点压力以下时,原油的黏度和密度快速增大,原油物性急剧变差。因此,对于成熟度较高的页岩油,利用注气补充地层能量并维持良好的原油物性是提高采收率的关键,且注CO_(2)对原油的膨胀、降黏效果均优于注烃类气。此外,注CO_(2)/烃类气可使古龙页岩油由弱挥发性油藏向挥发性油藏转变,先注烃类气再注CO_(2)使得古龙页岩油呈现出由挥发性油藏进一步向凝析气藏过渡的趋势。古龙页岩油脱气后的溶解气驱效果更优,产出油相呈现连续的泡沫油状态。注CO_(2)/烃类气可为地层原油补充溶解气和弹性能量,注CO_(2)对原油中间烃组分(C_(5)—C_(10))和重烃组分(C_(11)+)的抽提效果均较好,注烃类气对原油中间烃组分的抽提效果更好。 展开更多
关键词 古龙页岩油 相态特征 注CO_(2)/烃类气 多周期注气采油 溶解气驱 组分传质
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Mori fructus aqueous extracts attenuates liver injury by inhibiting ferroptosis via the Nrf2 pathway 被引量:3
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作者 Yuanyuan Wei Chen Gao +5 位作者 Huiru Wang Yannan Zhang Jinhua Gu Xiuying Zhang Xuhao Gong Zhihui Hao 《Journal of Animal Science and Biotechnology》 SCIE CAS CSCD 2023年第4期1418-1437,共20页
Background Liver fibrosis and hepatocellular carcinogenesis secondary to liver fibrosis are serious liver diseases with no effective treatments.Mori fructus aqueous extracts(MFAEs)have served as successful treatments ... Background Liver fibrosis and hepatocellular carcinogenesis secondary to liver fibrosis are serious liver diseases with no effective treatments.Mori fructus aqueous extracts(MFAEs)have served as successful treatments for many types of liver injury including fibrosis although the molecular mechanisms are unknown at present.Purpose To investigate the effect of MFAEs in alleviating acute and chronic liver injury and tried to decipher the underlying mechanism.Methods and results Mice were divided into 5 groups(n ps:contro=8)for acute(groups:control,0.3%CCl_(4),bifendate(BD),100 and 200 mg/kg MFAEs,7 d)and chronic(groul,10%CCl_(4),BD,100 and 200 mg/kg MFAEs,4 weeks)liver injury study.Each mouse was injected intraperitoneally with 10μL/g corn oil containing CCl_(4)expect the control group.HepG2 cells were used in vitro study.Eighteen communal components were identified by UPLC-LTQOrbitrap-MS.We utilized a mouse model for acute and chronic liver injury using CCl_(4)and MFAEs administration effectively blocked fibrosis and significantly inhibited inflammation in the liver.MFAEs activated the nuclear factor erythroid derived 2 like 2/heme oxygenase 1(Nrf2/HO-1)pathway and promoted the synthesis of the antioxidants glutathione(GSH),superoxidedismutase(SOD)and glutathione peroxidase(GSH-Px)that resulted in reduced levels of CCl_(4)-induced oxidative stress molecules including reactive oxygen species.These extracts administered to mice also inhibited ferroptosis in the liver by regulating the expression of Acyl-CoA synthetase long chain family member 4(ACSL4),solute carrier family 7 member 11(SLC7A11)and glutathione peroxidase 4(GPX4),thus reducing the occurrence of liver fibrosis.Both in vivo and in vitro tests indicated that the mechanism of MFAEs protection against liver fibrosis was linked to activation of Nrf2 signaling.These effects were blocked in vitro by the addition of a specific Nrf2 inhibitor.Conclusion MFAEs inhibited oxidative stress,ferroptosis and inflammation of the liver by activating Nrf2 signal pathway and provided a significant protective effect against CCl_(4)-induced liver fibrosis. 展开更多
关键词 Acute and chronic liver injury Ferroptosis Mori fructus aqueous extracts NRF2 Oxidative stress
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高含CO_(2)凝析气藏成藏过程中的流体相行为及油环体积预测
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作者 陈浩 左名圣 +5 位作者 王红平 王朝锋 徐程浩 杨柳 刘希良 袁志文 《吉林大学学报(地球科学版)》 CAS CSCD 北大核心 2024年第5期1506-1518,共13页
成藏后期的CO_(2)充注导致里贝拉区块高含CO_(2)次生凝析气藏的流体相行为十分复杂,油环体积预测难度很大。本文通过流体相平衡模拟、组分梯度分布计算及CO_(2)充注可视化实验,刻画了CO_(2)充注过程中的油气相行为,揭示了油环体积的动... 成藏后期的CO_(2)充注导致里贝拉区块高含CO_(2)次生凝析气藏的流体相行为十分复杂,油环体积预测难度很大。本文通过流体相平衡模拟、组分梯度分布计算及CO_(2)充注可视化实验,刻画了CO_(2)充注过程中的油气相行为,揭示了油环体积的动态变化规律,建立了基于气顶气组分拟合的高含CO_(2)次生凝析气藏油环体积预测新方法。研究结果表明:1)CO_(2)充注下的油环体积变化分为4个阶段:充注初期,油环以溶胀为主;充注前期,CO_(2)不断置换并萃取油相中的轻质组分,油环体积迅速降低;充注中期,CO_(2)持续萃取油相的轻、中质组分,油环体积缓慢减小;充注后期,CO_(2)-原油组分传质作用明显减弱,压缩效应导致油环体积进一步减小。2)轻质组分的强流动性使气顶气组成均一,重力分异作用使纵向上油环组分呈梯度变化。3)油环体积与气顶气组成和气油比密切相关。4)基于气顶气拟合新方法和不同井深现场勘探预测的油环体积占比分别为19.21%和22.30%,与CO_(2)充注可视化实验获得的油环体积占比(20.60%)较为吻合。 展开更多
关键词 气藏 CO_(2)-原油组分传质 流体相行为 油环体积预测 组分梯度分布 可视化实验
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Parameter Extraction for 2-π Equivalent Circuit Model of RF CMOS Spiral Inductors 被引量:1
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作者 高巍 余志平 《Journal of Semiconductors》 EI CAS CSCD 北大核心 2006年第4期667-673,共7页
A novel parameter extraction method with rational functions is presented for the 2-πequivalent circuit model of RF CMOS spiral inductors. The final S-parameters simulated by the circuit model closely match experiment... A novel parameter extraction method with rational functions is presented for the 2-πequivalent circuit model of RF CMOS spiral inductors. The final S-parameters simulated by the circuit model closely match experimental data. The extraction strategy is straightforward and can be easily implemented as a CAD tool to model spiral inductors. The resulting circuit models will be very useful for RF circuit designers. 展开更多
关键词 2 compact model parameters extraction RF CMOS spiral inductors
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Fecal metabolomics reveals the positive effect of ethanol extract of propolis on T2DM mice 被引量:1
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作者 Chunmei Wang Huiting Zhao +4 位作者 Kai Xu Yali Du Jinjia Liu Jinfei Wang Yusuo Jiang 《Food Science and Human Wellness》 SCIE CSCD 2023年第1期161-172,共12页
A large number of studies have shown that propolis has positive effects in the treatment of type 2 diabetes mellitus(T2DM).However,there are have only been a few reports that are based on an ultra-high performance liq... A large number of studies have shown that propolis has positive effects in the treatment of type 2 diabetes mellitus(T2DM).However,there are have only been a few reports that are based on an ultra-high performance liquid chromatography-quadrupole-time-of-flight-mass spectrometry(UPLC-Q-TOF-MS)analysis of the fecal metabolomics of ethanol extract of propolis(EEP)in the treatment of T2DM.The present investigation was designed to screen potential biomarkers of T2DM by the metabonomic method and to explain the possible anti-diabetes mechanism of EEP according to the changes in the biomarkers.The results showed that EEP improved the body weight(BW)of T2DM mice,lowered blood sugar levels,and significantly restored blood biochemical indicators related to T2DM,such as fasting insulin(FINS),homeostasis model assessment of insulin resistance(HOMA-IR),aspartate transaminase(AST),and alanine aminotransferase(ALT).Liver pathology showed that EEP reversed liver damage caused by T2DM.Metabolomics data identified 27 potential biomarkers in fecal samples.EEP effectively regulated the dysfunction in the metabolic pathways of glycerophospholipids,sphingolipids,riboflavins,and sterol lipids caused by T2DM.In summary,our research results revealed positive effects of EEP in the treatment of T2DM and provided potential candidate markers for further research and in the clinical treatment of T2DM. 展开更多
关键词 Ethanol extract of propolis Type 2 diabetes mellitus Fecal metabolites UPLC-Q-TOF-MS Metabolomics
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具有自萃取功能的相变CO_(2)吸收剂体系开发 被引量:1
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作者 陆诗建 刘含笑 +5 位作者 吴黎明 方梦祥 俞徐林 赵东亚 刘玲 康国俊 《中国电机工程学报》 EI CSCD 北大核心 2024年第1期203-213,I0017,共12页
二氧化碳(CO_(2))捕集工程应用的吸收剂存在再生能耗高、传质速率低、运行损耗大等问题,严重制约了CO_(2)捕集技术的大规模推广应用。为解决这些问题,该文开发适用于低分压CO_(2)捕集的相变吸收剂。该相变吸收体系以亲水性胺N-氨乙基哌... 二氧化碳(CO_(2))捕集工程应用的吸收剂存在再生能耗高、传质速率低、运行损耗大等问题,严重制约了CO_(2)捕集技术的大规模推广应用。为解决这些问题,该文开发适用于低分压CO_(2)捕集的相变吸收剂。该相变吸收体系以亲水性胺N-氨乙基哌嗪(N-aminoethyl piperazine,AEP)为主吸收体系,添加亲脂性分相剂二正丁胺(Di-n-butylamine,DPA)和活化剂(activator,ACT)。通过核磁共振波谱(nuclear magnetic resonance,NMR)和捕集CO_(2)连续测试实验研究该相变吸收剂的性能。实验结果表明,吸收负载达1.082 mol CO_(2)/mol溶液,再生温度降至98.5℃,具有优异的吸收性能和解吸性能。NMR分析表明,反应产物具有氨基甲酸盐分子结构,捕集CO_(2)连续测试实验研究与同浓度3 mol/L一乙醇胺(Monoethanolamine,MEA)溶液进行对比分析可知,相同再生能耗下,单位体积同浓度相变体系相比MEA吸收容量提高33%以上;相同再生能耗下相变体系的再生率比MEA提高15%,相同再生率下相变体系的再生能耗比MEA降低31%以上。结果表明,该相变吸收剂对于低分压CO_(2)捕集具有良好的应用前景。 展开更多
关键词 CO_(2)捕集 亲水性胺 亲酯性胺 再生能耗 自萃取 相变体系
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Synergistic extraction of rare earth by mixtures of 2-ethylhexyl phosphoric acid mono-2-ethylhexyl ester and di-(2-ethylhexyl) phosphoric acid from sulfuric acid medium 被引量:9
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作者 黄小卫 李建宁 +3 位作者 龙志奇 张永奇 薛向欣 朱兆武 《Journal of Rare Earths》 SCIE EI CAS CSCD 2008年第3期410-413,共4页
The extraction of Nd^3+ and Sm^3+, including the extraction and stripping capability as well as the separation effect of Nd^3+ or Sm^3+, from a sulfuric acid medium, by mixtures of di-(2-ethylhexyl) phosphoric a... The extraction of Nd^3+ and Sm^3+, including the extraction and stripping capability as well as the separation effect of Nd^3+ or Sm^3+, from a sulfuric acid medium, by mixtures of di-(2-ethylhexyl) phosphoric acid (HDEHP, H2A2(0)) and 2-ethylhexyl phosphoric acid mono-2-ethylhexyl ester (HEH/EHP, H2L2(0)) were studied. The distribution ratios and synergistic coefficients of Nd^3+ and Sm^3+ in different acidities were also determined. A synergistic extractive effect was found when HDEHP and HEH/EHP were used as mixed extractants for Sm^3+ or Nd^3+. The chemical compositions of the extracted complex were determined as Nd.(HA2)2-HL2 and Sm.(HA2)2-HL2. The extraction equilibrium constants, enthalpy change, and entropy change of the extraction reaction were also determined. 展开更多
关键词 di-(2-ethylhexyl) phosphoric acid 2-ethylhexyl phosphoric acid mono-2-ethylhexyl ester synergistic extraction mechanism Sm^3+ Nd^3+ rare earths
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The Effect of Simvastatin on mRNA Expression of Transforming Growth Factor-β1,Bone Morphogenetic Protein-2 and Vascular Endothelial Growth Factor in Tooth Extraction Socket 被引量:10
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作者 Chang Liu Zhe Wu Hong-chen Sun 《International Journal of Oral Science》 SCIE CAS CSCD 2009年第2期90-98,共9页
Aim To determine the effect of local simvastatin application on the mRNA expression level of transforming growth factor-β1 (TGF-β1), bone morphogenetic protein-2 (BMP-2) and vascular endothelial growth factor (... Aim To determine the effect of local simvastatin application on the mRNA expression level of transforming growth factor-β1 (TGF-β1), bone morphogenetic protein-2 (BMP-2) and vascular endothelial growth factor (VEGF) in the tooth sockets of rat. Methodology Forty-eight male Wistar rats were randomly divided into experimental and control groups (n=24). Polylactic acid/polyglycolic acid copolymer carriers, with or without simvastatin, were implanted into extraction sockets of right mandibular incisors. The expression of TGF-β1, BMP-2 and VEGF mRNA was determined by in situ hybridization in the tooth extraction socket at five days, one week, two weeks and four weeks after implantation. Results The fusiform stroma cells in the tooth extraction socket began to express TGF-β1, BMP-2 and VEGF mRNA in both experimental and control groups from one week after tooth extraction until the end of experiment. The expression of TGF-131 and BMP-2 mRNA in the experimental group was significantly up-regulated after one, two and four weeks, and expression of VEGF mRNA was significantly increased after one and two weeks compared with that in the control group. Conclusion The findings indicate that local administration of simvastatin can influence alveolar bone remodeling by regulating the expression of a school of growth factors which are crucial to osteogenesis in the tooth extraction socket. 展开更多
关键词 bone morphogenetic protein-2 (BMP-2 in situ hybridization SIMVASTATIN tooth extraction socket transforming growth factor-β1 (TGF-β1) vascular endothelial growth factor (VEGF)
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Separation of nickel, cobalt and copper by solvent extraction with P204 被引量:4
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作者 钱东 王开毅 +3 位作者 潘春跃 唐有根 蔡春林 蒋金枝 《中国有色金属学会会刊:英文版》 CSCD 2001年第5期803-805,共3页
Nickel, cobalt and copper were separated by solvent extraction with P204. The experimental results show that [Co(NH 3) 6] 3+ is an inert complex in extraction kinetics, therefore cobalt can be separated from nickel an... Nickel, cobalt and copper were separated by solvent extraction with P204. The experimental results show that [Co(NH 3) 6] 3+ is an inert complex in extraction kinetics, therefore cobalt can be separated from nickel and copper by non equilibrium solvent extraction. Under the conditions of temperature 25?℃, contact time of two phases 10?min, phase ratio 1∶1, aqueous pH 10.10 and concentration of P204 20%, [Co(NH 3) 6] 3+ is hardly extracted by P204, while the percentage extractions of nickel and copper are 79.3% and 93.9% respectively. Nickel and copper are separated by equilibrium solvent extraction with P204. Under the conditions of temperature 25?℃, contact time of two phases 1?min, phase ratio 1∶1, equilibrium pH 4.01 and concentration of P204 20%, the separation factor of copper and nickel is 216. 展开更多
关键词 non equilibrium solvent extraction equilibrium solvent extraction NICKEL COBALT COPPER di(2 ethylhexyl) phosphate
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