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ANTAGONISM BETWEEN SELENIUM AND HUMIC ACID

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Science China Chemistry 1987年第1期30卷 66-74页

作者：彭安徐朗秋 Beijing Institute of Environmental Chemistry Academia Sinica

In this work, two groups of experiments have been done by using mice and luminous bac-teria. The resnlts show that there exists an antagonism in toxicity between selenium andhumic acid (HA) extracted from the drinking water in Kaschin Beck disease regions. In order tostudy the chemical mechanism of the antagonism, gel filtration and X-ray photoelectron spec-troscopy techniques have been used to study the chemical bonding of the synthetic HA-Se insolution. The relationship between Se and HA in the cause of Kaschin Beck disease isdiscussed.

关键词： fa IV 叫叫

A Direct Approach for Finding Loop Transformation Matrices

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Journal of Computer Science & Technology 1996年第3期11卷 237-256页

作者：林华吕密方之熙 ElectricalEngineeringDepartmentTexasA＆MUniversity CollegeStationTX77843U.S.A

Loop transformations, such as loop interchange, reversal and skewing, have been unified under linear matrix transformations. A legal transformation matrix is usually generated based upon distance vectors or direction vectors. Unfortunately, for some nested loops, distance vectors may not be computable and direction vectors, on the other hand, may not contain useful information. We propose the use of linear equations or inequalities of distance vectors to approximate data dependence. This approach is advantageous since (1) many loops having no constant distance vectors have very simple equations of distance vectors; (2) these equations contain more information than direction vectors do, thus the cliance of exploiting potential parallelism is improved.In general, the equations or inequalities that approximate the data dependence of a given nested loop is not unique, hence classification is discussed for the purpose of loop transformation. Efficient algorithms are developed to generate all kinds of linear equations of distance vectors for a given nested loop. The issue of how to obtain a desired transformation matrix from those equations is also addressed.

关键词： A Direct Approach for Finding Loop Transformation Matrices FI fa

Achieving the nitrite pathway using fa inhibition and process control in UASB-SBR system removing nitrogen from landfill leachate

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Science China Chemistry 2010年第5期53卷 1209-1215页

作者： Sun, HongWei Yang, Qing Dong, GuoRi Hou, HongXun Zhang, ShuJun Yang, YingYing Peng, YongZhen Key Laboratory of Beijing Water Quality Science and Water Environment Recovery Engineering Beijing University of Technology Beijing 100124 China Anhui Guozhen Environmental Projection Sci. and Tech. Co. Ltd. Hefei 230088 China

An up-flow sludge blanket(UASB) and sequencing batch reactor(SBR) system was introduced to remove organics and nitrogen from landfill leachate.The synergetic effect of free ammonia(fa) inhibition and process control was used to achieve the nitrite pathway in the SBR.In previous research,inhibition of fa on nitrite oxidizing bacteria(NOB) activity has been revealed and the process control parameters(DO,ORP and pH) exactly indicate the end-point of nitritation.The method was implemented in the SBR achieving stable nitrogen removal via the nitrite pathway from landfill leachate.The degree of nitrite accumulation during the nitritation was monitored along with the simultaneous and advanced removal of organics and nitrogen in the UASB-SBR system.The nitrifying bacteria community was quantitatively analyzed by fluorescence in situ hybridization(FISH) techniques.Batch tests were carried out to investigate the denitritation kinetics of microbial bacteria in the SBR.Experimental results showed that the nitrite pathway could be repeatedly and reliably achieved by synergetic effect of fa inhibition and process control.FISH analysis showed the dominant nitrifying bacteria were ammonia-oxidizing β-Proteobacteria. Relationship between nitrite concentration and nitrite reduction rate followed the Monod-type equation.The maximum specific nitrite utilization rate(k) and half-velocity constant(Ks) were calculated as 0.44 gN gVSS-1d-1and 15.8 mg L-1,respectively.

关键词： landfill leachate partial nitrification fa FISH process control kinetic

Spectral-domain optical coherence tomography dynamic changes and steroid response in multiple evanescent white dot syndrome

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International Journal of Ophthalmology(English edition) 2017年第8期10卷 1331-1333页

作者： Yan Sheng Wen Sun Yang-Shun Gu Department of Ophthalmology the First Affiliated HospitalCollege of Medicine Zhejiang University Hangzhou 310003Zhejiang Province China

Dear Editor,Multiple evanescent white dot syndrome （MEWDS） was first described in 1984 as a rare, acute, unilateral,multifocal retinochoroidal disorder, typically affecting young myopic women. Previous studies with fluorescein angiography （fa） and electrophysiology suggested that MEWDS to be a disease in the retinal pigment epithelium （RPE） or outer retina, while recent studies with spectral- domain optical coherence tomography （SD-OCT） suggested it may be an outer retinal disease due to observation of hyperreflective material in outer retina and subtle disruptionsof the ellipsoid zone without RPE disruption.

关键词： OS DS ICGA fa Spectral-domain optical coherence tomography dynamic changes and steroid response in multiple evanescent white dot syndrome Figure

不同利用方式对黑钙土腐殖质组分剖面分布特征的影响

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东北林业大学学报 2022年第8期50卷 104-110页

作者：李春丽董军王鸿斌王丽群赵兰坡吉林农业大学长春130118 吉林省土地整治中心

为研究土地利用方式对土壤腐殖质组分的影响,以东北黑钙土区天然草地、人工林地和耕地为研究对象,采集0~100 cm土体中不同土层样品(腐殖质层、过渡层、石灰淀积层、过渡层和母质层),分析了不同利用方式土壤胡敏酸(HA)、富里酸(fa)和胡敏... 详细信息

为研究土地利用方式对土壤腐殖质组分的影响,以东北黑钙土区天然草地、人工林地和耕地为研究对象,采集0~100 cm土体中不同土层样品(腐殖质层、过渡层、石灰淀积层、过渡层和母质层),分析了不同利用方式土壤胡敏酸(HA)、富里酸(fa)和胡敏素(HM)质量分数和性质特征,从而为应对不同利用方式土壤固碳和提高黑钙土的可持续利用提供科学依据。结果表明:3种利用方式黑钙土腐殖质组分质量分数和性质明显不同。由腐殖质层至母质层,草地、林地和耕地土壤腐殖质各组分质量分数均随土层加深降低,HA、fa占土壤总有机碳比例随土层加深增加,而HM占土壤总有机碳比例随土层加深减少。草地转换为林地和开垦为耕地后,均造成HA、fa和HM质量分数减少,HA分别减少了14%、9%,fa分别减少了16%、17%,HM分别减少了4%、15%。不同利用方式土壤剖面中HA质量分数的差异在各土层都有发生,fa质量分数的差异主要发生在腐殖质层和淀积层以下的土层,说明土地利用方式对HA、fa的影响机制不同,易分解的fa在表层容易受到土地利用方式的影响。从腐殖质层至母质层,草地、林地和耕地土壤w(HA)∶w(fa)比值整体呈增加趋势,土壤有机质的稳定程度增强。草地土壤剖面HA和fa质量分数都高于林地和耕地,但w(HA)∶w(fa)比值总体上低于林地和耕地,反映了fa化学活性较高,易于矿化,开垦后其质量分数下降较快,不利于土壤fa的积累。

关键词：土地利用方式腐殖质 HA fa 黑钙土

Anti-insulin resistant effect of ferulic acid on high fat diet-induced obese mice

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Asian Pacific Journal of Tropical Biomedicine 2018年第12期8卷 604-608页

作者： Jarinyaporn Naowaboot Pritsana Piyabhan Pholawat Tingpej Narongsuk Munkong Wason Parklak Patchareewan Pannangpetch Division of Pharmacology Department of Preclinical ScienceFaculty of MedicineThammasat University (Rangsit Campus) Division of Physiology Department of Preclinical ScienceFaculty of MedicineThammasat University (Rangsit Campus) Division of Microbiology Department of Preclinical ScienceFaculty of MedicineThammasat University (Rangsit Campus) Division of Pathology School of MedicineUniversity of Phayao Graduate Academy Faculty of MedicineThammasat University (Rangsit Campus) Department of Pharmacology Faculty of MedicineKhon Kaen University

Objective: To evaluate the insulin sensitivity action of ferulic acid(fa) in skeletal muscle and hypothalamus of high-fat diet(HFD)-induced obese mice. Methods: Obese mouse model was induced by HFD(45 kcal% lard fat) for 16 weeks. After 8 weeks of HFD feeding, these obese mice were orally treated with fa at doses of 25 and 50 mg/kg/day for 8 weeks. At the end of all treatments, the epididymal fat, pancreas, skeletal muscle and hypothalamus were removed for biochemical parameter and protein expression examinations. Results: fa treatment significantly decreased leptin level in fat tissue and insulin level in pancreas(P fa increased the protein expressions of insulin receptor substrate-1, phosphatidylinositol 3-kinase, and phosphorylated-protein kinase B in both muscle and brain(P fa compared to untreated obese mice. Conclusions: These findings indicate the beneficial effect of fa in improving insulin resistance in HFD-induced obese mice. These effects are probably mediated via modulating the insulin receptor substrate/phosphatidylinositol 3-kinase/protein kinase B or adenosine monophosphate-activated protein kinase pathways.

关键词： protein obese mice insulin fa

基于Ifa和TDOA的变压器局部放电特高频定位方法

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计算机应用与软件 2023年第1期40卷 111-116页

作者：马鹏墀王致杰刘永慧沈盼王鸿付晓琳杨皖昊上海电机学院上海201306 江苏宏源电气有限责任公司江苏南京211100

非线性球面方程组的求解是变压器局部放电定位的关键技术之一,针对定位算法对时延误差敏感、容易陷入局部最优或误解等问题,提出基于改进萤火虫算法的变压器局部放电特高频定位方法。给出局部放电的定位模型和目标函数,对定位算法的适... 详细信息

非线性球面方程组的求解是变压器局部放电定位的关键技术之一,针对定位算法对时延误差敏感、容易陷入局部最优或误解等问题,提出基于改进萤火虫算法的变压器局部放电特高频定位方法。给出局部放电的定位模型和目标函数,对定位算法的适应度函数进行改进,对萤火虫算法的初始种群选择策略和萤火虫个体更新策略进行改进。仿真过程中,在理论时延下验证改进算法的可行性,通过改变时延大小模拟实际测量时的时延误差,并与其他定位算法进行对比,发现改进的定位算法平均定位误差为10.53 cm,满足定位精度要求。通过实验进一步验证了该算法的有效性和适用性。

关键词：变压器局部放电 TDOA UHF 定位算法 fa

Study on the condensation and crosslinking reactions of furfuryl alcohol and tris(2-hy-droxyethyl)isocyanurate by thermal methods

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Chinese Journal of Chemistry 1991年第3期9卷 193-198页

作者： CHEN,Xue-Si ZHENG,Guo-Dong LIU,Zhen-Hai XU,Ji-Ping Changchun Institute of Applied Chemistry,Academia Sinica,Changchun 130022 Changchun Institute of Applied Chemistry Academia Sinica Changchun 130022

Condensation and crosslinking reactions of furfuryl alcohol(fa)and fa with tris(2-hydro- xyethyl)isocyanurate(THEIC)are studied by means of DSC,TG,TBA,NMR and elemental analysis. Four exothermic peaks are observed on the DSC curves of thermal condensation of fa and fa with THEIC in the presence of sulfuric acid.The peaks Ⅰ,Ⅱ(50—80℃),Ⅲ(110—130℃)and Ⅳ(150— 190℃)correspond to linear polycondensation of fa through head-to-tail condensation,head-to-head etherification,crosslinking dehydration reaction between methylene group and terminal hydroxy group of fa polymeric chain and to further crosslinking reaction at higher temperature,respectively.The reactivity of fa and THEIC increases sharply at 130—150℃ and THEIC is reacted completely at 150℃.Addition of THEIC raises the initial decomposition temperature of fa polymer by 60℃.

关键词： fa Study on the condensation and crosslinking reactions of furfuryl alcohol and tris hy-droxyethyl)isocyanurate by thermal methods

人参皂苷Rg5及同分异构体金纳米颗粒的制备及活性研究

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人参皂苷Rg5及同分异构体金纳米颗粒的制备及活性研究

作者：张浩然吉林化工学院

学位级别：硕士

稀有人参皂苷Rg5是一种次级人参皂苷,是原人参二醇组皂苷的降解产物,具有Rk1和Rz1两种同分异构体。人参皂苷Rg5与其他主要人参皂苷相比,具有更强的抗癌、抗炎、抗糖尿病、神经保护和心脏保护等药理活性,是潜在的天然药物。人参皂苷Rg5/R... 详细信息

稀有人参皂苷Rg5是一种次级人参皂苷,是原人参二醇组皂苷的降解产物,具有Rk1和Rz1两种同分异构体。人参皂苷Rg5与其他主要人参皂苷相比,具有更强的抗癌、抗炎、抗糖尿病、神经保护和心脏保护等药理活性,是潜在的天然药物。人参皂苷Rg5/Rk1/Rz1稳定性差,严重影响在药物方面的开发应用,因此通过对Rg5/Rk1/Rz1的衍生化改变其结构,从而提高其稳定性、生物利用度和生物活性具有重要意义。本文以富含人参皂苷Rg5及其同分异构体的人参须根提取物(PGFRE)为还原剂和稳定剂,水作为反应溶剂,探索并优化了一种基于环境友好的生物还原法制备人参提取物金纳米颗粒(PGFRE-Au Nps)的方法;通过紫外可见光谱法考察了PGFRE-Au Nps的稳定性;通过MTT法研究了PGFRE-Au Nps对胃癌细胞(SGC7901)、乳腺癌细胞(4T1)、宫颈癌细胞(Hela)、肝癌细胞(Hep G2)和结肠癌细胞(MC38)的体外细胞毒性。实验结果表明,当反应时间为9 min、PGFRE浓度为8 mg/m L、反应温度为80℃及p H值为3.62(反应溶液初始p H值)时,可以得到均匀且稳定分散的PGFRE-Au Nps;通过对PGFRE-Au Nps溶液进行连续5周的紫外可见光谱监测结果表明,PGFRE-Au Nps的特征吸收峰随着时间的推移无明显的变化,表明PGFRE-Au Nps的稳定性良好;对癌细胞的MTT实验研究表明,PGFRE-Au Nps对SGC7901、4T1、Hela、Hep G2和MC38均有抑制作用,且显示出浓度依赖性。其中,当PGFRE-Au Nps浓度为150μg/m L时,4T1存活率为64.5%±3.1,浓度为200μg/m L时,MC38存活率为58.5%±8.5,显示出良好的癌细胞毒性。以Rg5/Rk1/Rz1混合物为还原剂和稳定剂,水作为反应溶剂,探索并优化了生物还原法制备Rg5/Rk1/Rz1的金纳米颗粒(Rg5/Rk1/Rz1-Au Nps)的方法,研究了Rg5/Rk1/Rz1-Au Nps的稳定性以及对SGC7901、4T1、Hela、Hep G2、MC38的细胞毒性。实验结果表明,在反应时间为35 min、Rg5/Rk1/Rz1混合物浓度为4 mg/m L、反应温度为80℃及p H值为2.62(反应溶液初始p H值)时,可以得到稳定分散的Rg5/Rk1/Rz1-Au Nps;对Rg5/Rk1/Rz1-Au Nps溶液进行了连续5周的紫外可见光谱的监测结果表明,Rg5/Rk1/Rz1-Au Nps的特征吸收峰随着时间的推移无明显的变化,表明Rg5/Rk1/Rz1-Au Nps有良好的稳定性。MTT实验结果表明,Rg5/Rk1/Rz1-Au Nps对SGC7901、4T1、Hela、Hep G2和MC38的细胞毒性优于PGFRE-Au Nps。其中,Rg5/Rk1/Rz1-Au Nps浓度为200μg/m L时,4T1和MC38癌细胞的存活率分别为47.5%±1.4和48.7%±2.7,明显低于PGFRE-Au Nps64.5%±3.1和58.5%±8.5,显示出更优异的抗癌活性。以Rg5/Rk1/Rz1混合物和fa为原料,PEG为连接臂,经过4步反应首次合成了fa和PEG修饰的人参皂苷衍生物fa-PEG-Rg5/Rk1/Rz1,并通过TLC和H-NMR分析进行了结构表征。以fa-PEG-Rg5/Rk1/Rz1为还原剂和稳定剂,水作为反应溶剂制备了fa和PEG修饰的人参皂苷Rg5/Rk1/Rz1的金纳米颗粒(fa-PEG-Rg5/Rk1/Rz1-Au Nps)。实验结果表明,fa-PEG-Rg5/Rk1/Rz1-Au Nps在反应时间为35 min、fa-PEG-Rg5/Rk1/Rz1浓度为5 mg/m L、反应温度为80℃及p H值为反应溶液初始p H值时,可以得到均匀且稳定分散的fa-PEG-Rg5/Rk1/Rz1-Au Nps。液相色谱分析表明,人参皂苷Rg5/Rk1/Rz1显示出良好的还原能力,可以在较短时间内完成Au Nps的合成。利用人参皂苷Rg5/Rk1/Rz1的还原能力将其转变成Rg5/Rk1/Rz1-Au Nps,可以显著提高其稳定性。通过对人参皂苷Rg5/Rk1/Rz1进行fa和PEG衍生化,有望显著提高其水溶性、靶向性和生物利用度,从而提高其药物活性。

关键词：人参皂苷Rg5/Rk1/Rz1 金纳米颗粒 fa PEG 稳定性细胞毒性