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Adsorption and correlation with their thermodynamic properties of triazine herbicides on soils

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Journal of Environmental Sciences 2003年第4期15卷 443-448页

作者： YANG Wei chun liu Wei ping liu hui jun liu Guang shen Institute of Environmental Science Zhejiang UniversityHangzhou 310027China.

Adsorption of atrazine, prometryne and prometon was determined on six soils with different physical and chemical properties. The adsorption isotherms of three herbicides could well fit Freundlich equation. On all of s... 详细信息

关键词： triazine herbicide soil adsorption excess thermodynamic properties

Adsorption of chloroacetanilide herbicides on soil (I) Structural influence of chloroacetanilide herbicide for their adsorption on soils and its components

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Journal of Environmental Sciences 2001年第1期13卷 37-45页

作者： liu Wei ping liu hui jun ZHENG Wei LU Jian hang Institute of Environmental Science Zhejiang University at Yuquan CampusHangzhou 310027China.

Adsorption of chloroacetanilide herbicide acetochlor, alachlor, metolachlor and propachlor on soils and soil components was determined, and the structural differences of these herbicides were used to explain the order of sorptivity. Adsorption isotherms for all herbicide-soil combinations conformed to the Freundlich equation, and Kf increased with increasing soil organic carbon content. Kd on soil humic acid was greater than that on clay, but association of humic acid with clay reduced the overall adsorption. On all soils and soil humic acids, herbicide adsorption decreased in the order: metolachlor > acetochlor > propachlor > alachlor. On Ca2+ - montmorrilonite, the order changed to metolachlor > acetochlor > alachlor > propachlor. FT-IR spectra of herbicide-clay or herbicide-humic acid-clay mixtures showed that H-bonding and charge transfer were the primary interaction pathways between these compounds and the surface of clay or humic acids. The different moieties attached to 2-chloro-acetanilide and their unique arrangement may have influenced the binding mechanisms and thus the sorptivity of these herbicides. This study indicates that the structural difference of pesticides in the same classes may be used as a molecular probe to obtain a better understanding of sorption mechanisms of pesticides on soil.

关键词： adsorption chloroacetanilide herbicides soil organic matter clay

Erosion-corrosion investigation of high chromium cast irons using newly designed jet type tester

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中国有色金属学会会刊：英文版 2004年第z1期14卷 405-412页

作者： TU Xiao-hui liu jun-quan LI Wei ZHANG Feng-hua SU jun-yi School of Materials Science and Engineering Xi''an Jiaotong University Xi''an 710049 China Wear Materials Research Center Guangzhou Research Institute of Nonferrous Metals Guangzhou 510651 China College of Industrial Equipment and Control Engineering South China University of Technology Guangzhou 510640 China Department of Chemistry Ji''nan University Guangzhou 510632 China Wear Materials Research Center Guangzhou Research Institute of Nonferrous Metals Guangzhou 510651 China School of Materials Science and Engineering Xi''an Jiaotong University Xi''an 710049 China

A jet type erosion-corrosion tester was developed for the erosion-corrosion investigation of high-chromium cast irons. During tests the size and the shape of particles in the slurry can be maintained stable. The jet velocity and attack angle can be accurately controlled. The repeatability and ranking consistency of the test results are satisfactory. The test parameters can be adjusted in a wide range, so that the tester can simulate various practical working conditions. Electrochemical test data can be automatically collected and processed. Dynamic polarization curves can be obtained during erosion-corrosion test, which can be used to study the dynamic corrosion *** high chromium cast irons were studied in hot concentrated alkaline slurry. The results show that the erosioncorrosion mass loss rate and dynamic corrosion rate of 295Cr26 iron is lower than that of 185Cr13 under the conditions similar to alumyte processing. The mechanism of erosion-corrosion of 295Cr26 and 185Cr13 was studied by using the tester. The interaction between erosion and corrosion was also quantitatively evaluated.

关键词： erosion-corrosion tester repeatability chromium cast iron hot concentrated alkali

Photodegradation of α-naphthaleneacetic acid in aqueous solution

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Journal of Environmental Sciences 2001年第3期13卷 361-364页

作者： liu hui jun, ZHOU Zhu fei, liu Wei ping (Environmental Science Institute, Zhejiang University, Hangzhou 310027, China. Environmental Science Institute Zhejiang University Hangzhou 310027 China.

Kinetic processes of a-naphthaleneacetic acid (NAA) photolysis were studied under different conditions. The results showed that the ultraviolet light was more effective than fluorescent light in promoting degradation, and the degradation of NAA under ultraviolet light followed the first order kinetics with the photolysis rate constant of 1.15 x 10-2 min-1 and half-life time (t1/2) of 60 min. Further, it was proved that the photolysis rate was higher in the presence of oxygen, titanium dioxide (TiO2), and low pH (acidic solution). At last, two photolysis intermediates were identified by GC-MS and possible photolysis pathways were proposed.

关键词： Acids Degradation Fluorescence Photolysis Solutions

Synthesis, Characterization, Polymerization of Optically Active Terminal Epoxides and Episulfides Bearing Bulky Groups

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Chemical Research in Chinese Universities 2013年第2期29卷 239-244页

作者： SUN Yun-kai ZHANG Jin liu hui-jun HE Li GONG Hang YANG Nian-fa Key Laboratory of Environmentally Friendly Chemistry and Applications of Ministry of Education College of Chemistry Xiangtan University Xiangtan 411105 P. R. China School of Chemistry and Chemical Engineering University of South China Hengyang 421001 P. R. China

A simple and efficient protocol was developed for the syntheses of optically active epoxides（2a--2d） via the reactions of epichlorohydrin with organometallic reagents with steric hindrance at low temperature. On this basis, episulfides（3a--3d） were obtained with high e.e. values by the reaction of the corresponding epoxides with NH4SCN. The configuration of thiiranes was opposite to that of the corresponding epoxides. Then, epoxides 2a--2d were anionically polymerized and the poly-R-2a（or poly-S-2a） was proved to keep a stable one-handed helical conforma- tion in solution. The oligomers[degree of polymerization（DP）=2--5] were obtained when the thiiranes（3a, 3b and 3c） were used to polymerize.

关键词： Optical activity Epoxide Episulfide One-handed helicity

Dendrobium officinale Kimura et Migo and American ginseng mixture: A Chinese herbal formulation for gut microbiota modulation

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Chinese Journal of Natural Medicines 2020年第6期18卷 446-459页

作者： liu Cheng-Zhi CHEN Wei WANG Mei-Xia WANG Ying CHEN Li-Qing ZHAO Feng SHI Ya liu hui-jun DOU Xiao-Bing liu Chao CHEN Huan Key laboratory of Microbial technology and Bioinformatics of Zhejiang Province Zhejiang Institute of MicrobiologyHangzhou 310012China NMPA Key laboratory for Testing and Risk Warning of Pharmaceutical Microbiology Zhejiang Institute of MicrobiologyHangzhou 310012China Hangzhou Huqing yu tang Traditional Chinese Medicine Mordernize Institute Hangzhou 311100China College of Life Science Zhejiang Chinese Medical UniversityHangzhou 310053China Department of Orthopaedics Sir Sun Run Shaw HospitalSchool of MedicineZhejiang UniversityHangzhou 310009China

Dendrobium officinale Kimura et Migo(D. officinale) is a famous traditional Chinese medicine(TCM). A mixture of D. officinale and American ginseng has been shown to enhance cell-mediated immunity, humoral immunity, and monocyte/macrophage functions in mice. Here, the effects of a D. officinale and American ginseng mixture on the structure of gut microbial community in dogs were examined using high-throughput 16S rRNA gene amplicon sequencing. The data revealed that while the mixture did not change the diversity of gut microbial community significantly, differences among individuals were significantly reduced. Furthermore, the mixture-responsive operational taxonomic units(OTUs) exhibited a phase-dependent expression pattern. Fifty-five OTUs were found to exhibit a mixture-induced expression pattern, among which one third were short-chain fatty acid(SCFA)-producing genera and the others were probiotic genera included Lactobacillus spp., Sutterella, Alistipes, Anaerovorax, Bilophila, Coprococcus, Gordonibacter, Oscillibacter, among others. By contrast, 36% of the OTUs exhibiting a mixture-repressed expression pattern were disease-associated microorganisms, and six genera, namely Actinomyces, Escherichia/Shigella, Fusobacterium, Slackia, Streptococcus and Solobacterium, were associated with cancer. In addition, five genera were closely associated with diabetes, namely Collinsella,Rothia, Howardella, Slackia and Intestinibacter. Our results indicate that this D. officinale and American ginseng mixture may be used as a prebiotic agent to enhance SCFA-producing genera and prevent gut dysbiosis.

关键词： Dendrobium officinale American Ginseng Gut Microbiota 16S rRNA

Peripheral Nerve Stimulation for Occipital Neuralgia

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Chinese Medical Journal 2015年第18期128卷 2553-2554页

作者： Ai-jun liu hui-jun Ji Yong-Cheng Jiao Zhi-Wen Zhang Department of Neurosurgery First Affiliated Hospital of Chinese People's Liberation Army General Hospital Beijing 100048 China

To the Editor： Occipital neuralgia （ON） is the third most common headache syndrome following migraine and tension-type headache. In recent years, peripheral nerve stimulation （PNS） has been used to relieve severe pain caused by some types of neuralgia when conservative medical treatments and block procedures were not effective. PNS is a kind of neuromodulation using spinal cord stimulation device to relieve neuralgias. Here. we presented a case in which a patient with refractory ON was treated successfully with PNS.

关键词：脊髓紧张型头痛神经痛肾病综合征疼痛头痛胰岛素综合征

Post-tunable salt gel electrolytes toward flexible supercapacitor switches

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Journal of Energy Chemistry 2025年第1期100卷 114-124页

作者： hui Wang Shuang Chen Xuming liu Qin Zhang Xin liu Polymeric and Soft Materials Laboratory School of Chemistry and Life Science and Advanced Institute of Materials ScienceChangchun University of TechnologyChangchun 130012JilinChina Polymeric and Soft Materials Laboratory School of Chemical Engineering and Advanced Institute of Materials ScienceChangchun University of TechnologyChangchun 130012JilinChina

Convertible hydrogel supercapacitors have emerged as promising energy storage devices in switches,diodes,and ***,inherent weaknesses in ionic conductivity,mechanical properties,and water retention of hydrogel electrolytes seriously hinder their *** by the hardness conversion of sea cucumber skin,a conductivity and mechanics dual-tunable salt gel electrolyte is successfully *** salt gel presents a reversible switching of conductors-insulators and a mechanical regulation between softness and hardness via the dissolution-crystallization transition of sodium acetate trihydrate(SAT).Meanwhile,the salt gels spontaneously grow a layer of“armor”through saturated phase-change salt crystals effectively reducing water evaporation of hydrogel ***,this phase-change soft-rigid conversion strategy will expand the capabilities of gel-based flexible supercapacitors(area capacitance:258.6 mF cm^(-2)),and the capacitance retention rate could still reach 86.9%after 3000 cycles at high ***,the salt gel supercapacitor is potentially used in over-heat alarm *** is anticipated that the strategy of conductivity and mechanics of dual-tunable salt gel would provide a new perspective on the development of energy storage devices,wearable electronics,and flexible robots.

关键词： Supercapacitors Salt gels Reversible phase transition Post-tuning Conductivity switching

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田间黄花梨糖度的可见/近红外光谱检测方法

光谱学与光谱分析 2015年第11期35卷 3078-3081页

作者：刘辉军应义斌浙江大学生物系统工程与食品科学学院浙江杭州310058 中国计量学院计量测试工程学院浙江杭州310018

提出了一种可克服背景光对田间光谱测量影响的方法。采集田间水果光谱时,环境背景光的干扰强,难以获取样品有效光谱信息。在田间采用套袋方式遮挡现场光线能得到较理想的结果,但检测效率低,仪器暗场校正和参考光谱校正等方法有利于减小... 详细信息

提出了一种可克服背景光对田间光谱测量影响的方法。采集田间水果光谱时,环境背景光的干扰强,难以获取样品有效光谱信息。在田间采用套袋方式遮挡现场光线能得到较理想的结果,但检测效率低,仪器暗场校正和参考光谱校正等方法有利于减小模型误差,但不能有效消除环境光照的干扰。通过在测量探头前加装快门,打开快门时测得样品在仪器光源和背景光共同作用下的现场光谱,关闭快门时测得样品仅在现场环境光线作用下的背景光谱,将背景光谱从现场光谱中扣除进行背景光校正。利用偏最二乘法建立田间(背景光校正前、后)以及室内样品光谱建立黄花梨糖度预测模型,预测值与真实值的相关系数分别为0.1,0.69,0.92,均方根误差分别为0.89°Brix,0.42°Brix,0.27°Brix,预测集的RPD分别为0.79,1.69,2.58,结果表明实验所采用的背景光校正方法可有效减小田间环境光照对黄花梨可见/近红外光谱采集的影响,可用于田间水果的近红外光谱采集,有利于充分发挥可见/近红外光谱技术在果实采收前的田间管理、采收成熟度检测等方面的潜力。

关键词：黄花梨可见/近红外光谱糖度田间背景光校正