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Effect of hydrogen bonding and hydrophobic interaction on the formation of supramolecular hydrogels formed by L-phenylalanine derivative hydrogelator

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Chinese Chemical Letters 2007年第8期18卷 1001-1004页

作者： Xin Jian Fu shu Qin Cao ning xia Wang Sheng Zu Zhang Hong wang Ya Jiang Yang Department of Chemistry Huazhong University of Science and Technology Wuhan 430074 China

A new hydrogelator, pyridinium bromide salt of N-6-bromohexanoyl-L-phenylamino octadecane, was synthesized. Supramolecular hydrogels can be formed through the self-assembly of this hydrogelator in water. In this work, D2O was used instead of H2O as solvent for FT-IR measurement due to the fact that it is impossible to obtain useful Fr-IR information on the hydrogen bonding in water. The investigation of PT-IR and steady-state fluorescence indicated that the driving forces for the self-assembly were mainly hydrogen bonding and hydrophobic interaction. Based on the data of XRD and molecular modeling, the possible mechanism of the formation of hydrogelator aggregates was proposed.

关键词： t-Phenylalanine derivatives Hydrogelator Supramolecular hydrogels

Thermal Convection in a Tilted Rectangular Cell with Aspect Ratio 0.5

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Chinese Physics Letters 2017年第10期34卷 52-55页

作者： Qi Wang Bo-Lun Xu shu-ning xia Zhen-Hua Wan De-Jun Sun Department of Modern Mechanics University of Science and Technology of China Hefei 230027 Shanghai Institute of Applied Mathematics and Mechanics Shanghai University Shanghai 200072

Thermal convection in a three-dimensional tilted rectangular cell with aspect ratio 0.5 is studied using direct nu- merical simulations within both Oberbeck-Boussinesq （OB） approximation and strong non-Oberbeck-Boussinesq （NOB） effects. The considered Rayleigh numbers Ra range from 105 to 107, the working fluid is air at 30OK, and the corresponding Prandtl number Pr is 0.71. Within the OB approximation, it is found that there exist multiple states for Ra = 105 and hysteresis for Ra = 106. For a relatively small tilt angle/3, the large-scale circulation can either orient along one of the the vertical diagonal planes （denoted by Ma mode） or orient parallel to the front wall （denoted by Mp mode）. Which of the two modes transports heat more efficiently is not definitive, and it depends on the Rayleigh number Ra. For/Ta = 107 and β = 0°, the time-averaged flow field contains four rolls in the upper half and lower half of the cell, respectively, Md and Mp modes only developing in tilted cells. By investigating NOB effects in tilted convection for fixed/Ta = 106, it is found that the NOB effects on the Nusselt number Nu, the Reynolds number Re and the central temperature Tc for different β ranges are different. NOB effects can either increase or decrease Nu, Re and Tc when β is varied.

关键词： Thermal Convection in a Tilted Rectangular Cell with Aspect Ratio 0.5 NOB Ra

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重复压裂井裂缝周围应力的重定向

大庆石油学院学报 2007年第4期31卷 37-40页

作者：宁淑霞大庆石油管理局钻井二公司黑龙江大庆163413

考虑重复压裂井周围注采流固耦合模型,建立垂直裂缝井孔隙压力变化的诱导应力模型;引入初次人工裂缝内流体影响因子,建立初次人工裂缝诱导应力场模型;考虑温度对储层岩石的影响,建立温度诱导应力模型.给出重复压裂造新缝的力学条件.计... 详细信息

考虑重复压裂井周围注采流固耦合模型,建立垂直裂缝井孔隙压力变化的诱导应力模型;引入初次人工裂缝内流体影响因子,建立初次人工裂缝诱导应力场模型;考虑温度对储层岩石的影响,建立温度诱导应力模型.给出重复压裂造新缝的力学条件.计算了某区块受3口注水井影响的1口油井周围应力,其理论计算结果与实测结果基本吻合.

关键词：重复压裂注采生产诱导应力场流固耦合

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反渗透(RO)前处理系统SDI优化实践

华北电力技术 2007年第9期 30-33,50页

作者：陈刚张羽翔宁淑霞新疆电力科学研究院新疆乌鲁木齐830000 独山子石化公司热电厂新疆克拉玛依833600

采用地表水的反渗透系统,经过混凝处理后外观清澈,经砂滤和活性炭过滤后浊度接近0.1 NTU,但污染指数(SD I)仍然在4以上,投运反渗透会导致产水量随时间的增加而递减速度加快,需要高压泵升压维持产水量,使反渗透膜寿命降低。本文就这一问... 详细信息

采用地表水的反渗透系统,经过混凝处理后外观清澈,经砂滤和活性炭过滤后浊度接近0.1 NTU,但污染指数(SD I)仍然在4以上,投运反渗透会导致产水量随时间的增加而递减速度加快,需要高压泵升压维持产水量,使反渗透膜寿命降低。本文就这一问题进行分析并提出了可行的解决方案。

关键词：地表水反渗透(RO) 污染指数(SDI) 混凝絮凝

CaH2-promoted activity of Ni-carbonate interface for CO2 methanation

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Journal of Energy Chemistry 2025年第1期100卷 522-532页

作者： Jin-Peng Wang Guo-Cui Mao Hui-Lin Jiang Bao-xia Dong Yun-Lei Teng School of Chemistry and Chemical Engineering Yangzhou University

Transition metal-carbonate interfaces often act as active sites in heterogeneous catalytic *** interface between transition metal and metal carbonate exhibits a dynamic equilibrium during the CO2hydrogenation reaction,involving surface carbonate hydrogenation and ***,there have been few reports on engineering the activity of the interface between transition metal and alkaline earth metal carbonate for catalytic *** work demonstrated that the incorporation of CaH2in Ni/CaCO3enhances the CO2methanation activity of the *** CO2conversion for Ni/CaH2-CaCO3reached 68.5%at 400°C,which was much higher than that of the Ni/CaCO3（31.6%） and Ni/CaH2-CaO （42.4%） ***,the Ni/CaH2-CaCO3catalysts remained stable during the stability test for 24 h at 400°C and 8 *** research revealed that CaH2played a crucial role in promoting the activity of the Ni-carbonate interface for ***2could modify the electronic structure of Ni and tune the structural properties of CaCO3to generate medium basic sites （OH groups）,which are favorable for the activation of H2and ***-situ Fourier transform infrared spectroscopy （FTIR） analysis combined with density functional theory calculations demonstrated that CO2activation occurs at the hydroxyl group （OH） on the CaH2-modified Ni-carbonate surface,leading to the formation of CO3H****,our study has confirmed that CO2methanation over the Ni/CaH2-CaCO3catalysts proceeds via the formate pathway.

关键词： Metal hydride Ni catalysts Carbonate Metal-carbonate interface

Effect of annealing treatment on microstructure and mechanical properties of Al/Ni multilayer composites during accumulative roll bonding (ARB) process

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Journal of Iron and Steel Research International 2020年第1期27卷 96-104页

作者： Hui-wen Zhu Bao-yi Yu Hao Zhang Bo-ning Yu shu-ning Lv Li Zheng Run-xia Li School of Material Science and Engineering Shenyang University of TechnologyShenyang 110870LiaoningChina School of Mechanical Engineering Dongguan University of TechnologyDongguan 523808GuangdongChina

Al/Ni multilayer composites are produced by accumulative roll bonding process and then annealed with different temperatures and *** images,microstructure and mechanical properties of Al/Ni multilayer composites are *** for the macroscopic images,although there was an edge crack along the rolling direction at the third pass,the defect of composites was not serious and the forming quality of composites was relatively *** yield strength and elongation of Al/Ni multilayer composites are improved after the annealing treatment;however,with the increase in annealing temperature and time,the yield strength and ciongation of Al/Ni multilayer composites are *** the process of annealing treatment,aluminum atoms diffuse in the way of vacancy diffusion,which results in the formation of Al3Ni intermetallic phase at Al/Ni interface and Kirkendall void in the aluminum *** content of Al3Ni intermetallic phase and Kirkenckill void would increase with the increase in annealing temperature and time.

关键词： Al/Ni multilayer composite Accumulative roll bonding process Annealing treatment Interrnetallic phase

New phenolic compounds from the leaves of Artocarpus heterophyllus

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Chinese Chemical Letters 2017年第1期28卷 37-40页

作者： xiao-Ling Wang xia-xia Di Tao Shen shu-Qi Wang xiao-ning Wang The Second Hospital of Shandong University Jinan 250033 China Department of Natural Product Chemistry Key Laboratory of Chemical Biology (Ministry of Education) School of Pharmaceutical Sciences Shandong University Jinan 250012 China

One new 2-arylbenzofuran derivative, artocarstilbene B（1）, one new benzaldehyde derivative,（E）-3,5-dihydroxy-4-（3-methylbut-1-enyl）benzaldehyde（2）, as well as 18 known compounds（3–20） were obtained from the leaves of Artocarpus heterophyllus. Their structures were elucidated on the basis of extensive spectroscopic techniques including 2D NMR and HR-ESIMS. Many compounds exhibited moderate to weak inhibitory activity against the proliferation of the PC-3, NCI-H460, and A549 cancer cell lines.

关键词： Artocarpus heterophyllus 2-Arylbenzofuran Artocarstilbene B( E)-3,5-Dihydroxy-4-(3-methylbut- 1 -enyl)benzaldehyde Cytotoxicity

Crystal structures, antibacterial activity and thermal decomposition kinetics of lanthanide complexes with 4-chloro-2-methoxybenzoic acid and 1,10-phenanthroline

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Chinese Science Bulletin 2014年第27期59卷 3398-3405页

作者： Ying-Ying Zhang shu-xia Ren Jian-Jun Zhang ning Ren shu-Ping Wang Testing and Analysis Center Hebei Normal University Material Science and Engineering School Shijiazhuang Tiedao University College of Chemistry and Material Science Hebei Normal University Department of Chemistry Handan College

A series of lanthanide complexes [Ln(4-Cl-2-MOBA)3phen]2(Ln=Sm(1), Nd(2), Ho(3), Eu(4), Dy(5), and Tb(6); 4-Cl-2-MOBA=4-chloro-2-methoxybenzoate, phen=1,10-phenanthroline) were synthesized and characterized. The single-crystal X-ray diffraction demonstrates that 1–3 are isomorphous, which present dimeric structures with four 4-Cl-2-MOBA anions function as bridging ligands. Complexes 1 and 4–6 display their characteristic luminescence emission bands of central Ln3?ions. The heat capacities, the thermodynamic functions and the thermogravimetry–Fourier transform infrared spectra of gaseous products of complexes 1–6 were *** non-isothermal kinetics of the second decomposition stage was studied by the integral isoconversional non-linear method and Stark method. Furthermore, 1–6 exhibited excellent antibacterial activity against Candida albicans,Escherichia coli and Staphylococcus aureu.

关键词：热分解动力学甲氧基苯甲酸稀土配合物晶体结构抗菌活性邻菲咯啉镧系元素金黄色葡萄球菌

呋虫胺和唑虫酰胺在茶叶加工过程中的残留特征及膳食风险评估

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食品科学 2025年第1期46卷 192-199页

作者：李春勇吕莹金静王霞秦曙山西农业大学山西功能农产品检验检测中心山西太原030031

为明确呋虫胺和唑虫酰胺微乳剂在茶叶种植、烘干、浸泡过程中的残留特征,在山东、浙江等10地开展规范农药登记残留田间试验,并进行加工因子校正膳食风险评估模型比较研究。样品经体积分数5%甲酸-乙腈提取、盐析分层、分散固相萃取净化后... 详细信息

为明确呋虫胺和唑虫酰胺微乳剂在茶叶种植、烘干、浸泡过程中的残留特征,在山东、浙江等10地开展规范农药登记残留田间试验,并进行加工因子校正膳食风险评估模型比较研究。样品经体积分数5%甲酸-乙腈提取、盐析分层、分散固相萃取净化后,经超高效液相色谱-串联质谱法检测,外标法定量。结果表明:在0.005~0.500μg/mL范围内,呋虫胺及其代谢物、唑虫酰胺质量浓度与其响应峰面积呈良好线性关系(R^(2)>0.99),在0.05、1.00、20.00、50.00 mg/kg(茶鲜叶、茶干叶),0.05、0.10、5.00 mg/kg(茶汤)添加水平下,呋虫胺及其代谢物1-甲基-3-[(3-四氢呋喃)甲基]脲、1-甲基-3-[(3-四氢呋喃)甲基]二氢胍盐的平均加标回收率为74%~103%,相对标准偏差为1%~9%;唑虫酰胺的平均加标回收率为75%~95%,相对标准偏差为1%~6%,方法定量限均为0.05 mg/kg;20%呋虫胺·唑虫酰胺微乳剂按推荐剂量施药后,呋虫胺(含代谢物)在茶鲜叶中的规范残留试验中值(supervised trials median residue,STMR)经烘干因子校正后与茶干叶中STMR相应的国家估算每日摄入量(national estimated daily intake,NEDI)均为4.08 mg,占每日允许摄入量(allowable daily intake,ADI)的32.4%;唑虫酰胺在茶鲜叶中的STMR经烘干因子校正后的NEDI为0.17581 mg,占ADI的46.5%,茶干叶中STMR对应的NEDI为0.18925 mg,占ADI的50.1%,呋虫胺和唑虫酰胺在不同评估模型下获得的长期膳食暴露风险均低于100%;呋虫胺(含代谢物)经加工因子校正后的国际短期膳食摄入量(international estimation of short-term dietary intake,IESTI)与校正前处于同一风险水平,低于急性参考剂量(acute reference dose,ARfD)(1 mg/kg);唑虫酰胺的IESTI为3.46×10^(-4) mg/kg(采收间隔7 d),低于ARf D(0.01 mg/kg),本研究方法在茶汤中未检测到唑虫酰胺残留,故未得到浸泡因子及相应的IESTI。综上,按推荐剂量在茶树上使用20%呋虫胺·唑虫酰胺微乳剂是安全的,最终残留量对应的长期及急性膳食摄入风险均在可接受范围,利用加工因子校正评估模型更切合实际风险水平。

关键词：呋虫胺唑虫酰胺茶叶加工因子残留特征风险评估