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141.
Sun Haitao Nan Zhaodong Liu Yongjun Zhang Honglin Zhang Tonglei 《Journal of Thermal Analysis and Calorimetry》1997,48(4):835-839
Bacterial growth power-time curves were determined with a 2277 Thermal Activity Monitor. Bacterial multiplication curves were measured at different temperatures and an experimental model was established. Both growth rate constants and lowest growth temperatures were calculated.Supported by the Natural Science Foundation of Shandong Province. 相似文献
142.
Yongjun He 《Applied Surface Science》2006,252(6):2115-2118
One-dimensional polyaniline nanostructures were synthesized by interfacial polymerization in a solids-stabilized oil/water emulsion for the first time. The products were characterized with TEM, FTIR and UV-vis. FTIR analyses proved the polyaniline synthesized were of emeraldine salt form; the results of TEM showed that when MgCO3 and CaCO3 particles were used as emulsifiers, polyaniline nanofibers with an average diameter of 33 nm and nanotubes with an average outer diameter of 28 nm were obtained, respectively. Comparing to ordinary interfacial polymerization approach, our new route needed much less amount of oil phase and shorter polymerization time. A possible mechanism for the formation of one-dimensional polyaniline nanostructures was suggested. 相似文献
143.
Shuang Liu Hong Zhang Yongjun Lu Xiaohui Qiu Wen Zhai 《Journal of Dispersion Science and Technology》2018,39(7):1018-1024
A novel amphoteric xanthan gum (AXG) containing anionic carboxyl groups and cationic quaternary ammonium substituents was prepared from xanthan gum (XG) and 3-chloro-2-hydroxypropyltriethanolammonium acetate. The rheological and microrheological properties of AXG and XG solutions were studied in this work. The rheological results showed that the apparent viscosity of the 0.4% AXG solution was 5.26 times that of the 0.4% XG solution, and the AXG solution exhibited more obvious thixotropy and much stronger viscoelasticity than the XG solution. Both experiment and numerical simulations were adopted to investigate the gel-breaking process of the AXG solution, and the rheokinetics equations can well describe the evolution of complex viscosity. Moreover, the optical microrheology method was also adopted to investigate the microrheological behavior of AXG and XG solutions. The microrheological results showed that the AXG solution exhibited higher viscosity index at zero shear and a more obvious solid-like behavior than the XG solution. Good agreement is found when comparing the results obtained from microrheology to classical rheology, which verifies the feasibility of the microrheology method for measuring the solution properties, especially some properties not well described by the current rheological approach. 相似文献
144.
Ultrathin Graphdiyne Nanosheets Grown In Situ on Copper Nanowires and Their Performance as Lithium‐Ion Battery Anodes 下载免费PDF全文
Hong Shang Zicheng Zuo Liang Li Fan Wang Huibiao Liu Yongjun Li Prof. Yuliang Li 《Angewandte Chemie (International ed. in English)》2018,57(3):774-778
A method is presented for the scalable preparation of high‐quality graphdiyne nanotubes and ultrathin graphdiyne nanosheets (average thickness: ca. 1.9 nm) using Cu nanowires as a catalyst. For the storage of Li+ ions, the graphdiyne nanostructures show a high capacity of 1388 mAh g?1 and high rate performance (870 mA h g?1 at 10 A g?1, and 449.8 mA h g?1 at 20 A g?1) with robust stability, demonstrating outstanding overall potential for its applications. 相似文献
145.
The oxidative degradation of nitrobenzene (NB) induced by gaseous glow discharge plasma in contact with aqueous solution was investigated.
The experimental results indicated that NB removal obeyed first-order kinetics under certain applied currents. The major degradation
byproducts such as nitrophenols, phenol, 1,3-dinitrobenzene and carboxylic acids have been detected. The distribution of nitrophenols
follows the order o- > p- > m- and oxalic, formic and acetic acids are major carboxylic intermediates. The eventual products were nitrate ion and carbon
dioxide. During the treatment, a large amount of hydrogen peroxide was produced. Addition of ferrous or ferric ions into the
solution greatly enhanced the degradation rate due to Fenton’s reaction. The energy efficiencies of NB removal and hydrogen peroxide formation were compared with those of other discharges. Hydroxyl radicals were shown
to be the most likely species responsible for NB degradation 相似文献
146.
本文提出了可逆逐级电子转移过程(n_1=n_2)的1.5次和2.5次微分电分析法(卷积伏安法)的理论公式,用计算机绘出了相应的理论曲线图,讨论了标准分离电位(△E~0)及电子转移数(n)对电流~电压曲线的影响.选用氯化铜(Ⅱ)-氨水-氯化铵体系进行了实验验证,其结果与理论完全相符. 相似文献
147.
Dongju Zhang Yongjun Liu Haiquan Hu Chengbu Liu 《International journal of quantum chemistry》2002,86(5):468-477
The inner‐shell reorganization and activation models of the electron‐transfer reactions of transition‐metal hexammine complexes are presented. The inner‐shell reorganization and activation energies of several hexammine redox pairs M(NH3)62+/3+ (M=Mn, Fe, and Co) in self‐exchange reactions are studied by different formalisms. The extent of the anharmonicities in the vibration between the metal–ion and the ligands in the reorganization process of these complexes is determined. The inner‐shell barriers of these redox pairs are dependent on reorganization model used. The contribution of the individual reactants to the inner‐shell barrier is sensitive to the model used. © 2001 John Wiley & Sons, Inc. Int J Quantum Chem, 2001 相似文献
148.
149.
Bin Yang Yuan Li Wentao Shi Yingying Liu Yongjun Kan Jinlong Chen Juan Hu Wensheng Pang 《Molecules (Basel, Switzerland)》2022,27(10)
Polysaccharides are abundant in natural resources and perform numerous physiological functions. Polysaccharide structures often lack chromophore groups; thus, current analytical methods cannot distinguish polysaccharide metabolites in the body or polysaccharide prototypes in biological samples. Thus, the measurement of polysaccharides in blood, bodily fluid, and cell-culture medium is difficult. Our early-stage research resulted in the isolation of two homogeneous polysaccharides from Pseudostellaria heterophylla, PHP0.5MSC-F and PHPH-1-2, which have anti-hyperglycemia and insulin resistance improvement effects for type 2 diabetes. In this study, the reducing terminal sugars of PHP0.5MSC-F and PHPH-1-2 were labeled with 2-aminobenzamide (2-AB) to prepare novel fluorescent probes for HPLC-coupled fluorescence detection (HPLC-FLD). Quantitative analysis was performed in reference to T40, and the detection limit for PHP0.5MSC-F was found to be 8.84 μg/mL with a linear range of 29.45–683.28 μg/mL. In reference to T70, the detection limit for PHPH-1-2 was found to be 13.89 μg/mL with a linear range of 46.29–462.76 μg/mL. This method was used to measure the bidirectional transport of polysaccharides across caco-2 cells from apical to basolateral (AP→BL) or from basolateral to apical (BL→AP) directions and to evaluate the polysaccharide bioavailability. The drug absorption capacity was determined based on the apparent permeability coefficient (Papp), and the Papp values for the two polysaccharides were found to be greater than 1 × 10−6 cm/s, which suggests easy absorption. Regarding bidirectional transport, the AP→BL Papp values were greater than the BL→AP values; thus, PHP0.5MSC-F and PHPH-1-2 mainly underwent passive transference. The two membrane permeable polysaccharides were not P-gp efflux transporter substrates. The absorption mechanism of PHP0.5MSC-F complies with passive diffusion under a concentration gradient, whereas PHPH-1-2 mainly utilizes a clathrin-mediated endocytic pathway to enter caco-2 cells. This innovative HPLC-FLD method can help to track polysaccharide internalization in vitro and in vivo to facilitate cellular uptake and biodistribution exploration. 相似文献
150.