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11.
The new nickel selenite chloride, Ni5(SeO3)4Cl2, was obtained by high-temperature solid state reaction of NiCl2, Ni2O3 and SeO2 in a 1:2:4 molar ratio at 700 °C in an evacuated quartz tube. Its structure was established by single-crystal X-ray diffraction. Ni5(SeO3)4Cl2 crystallizes in the triclinic system, space group P-1 (No. 2) with cell parameters of a=8.076(2), b=9.288(2), c=9.376(2) Å, α=101.97(3), β=105.60(3), γ=91.83(3)° and Z=2. All nickel(II) ions in Ni5(SeO3)4Cl2 are octahedrally coordinated by selenite oxygens or/and chloride anions (([Ni(1)O5Cl], [Ni(2)O4Cl2], [Ni(3)O5Cl], [Ni(4)O6] and [Ni(5)O4Cl]). The structure of the title compound features a condensed three-dimensional (3D) network built by Ni(II) ions interconnected by SeO32− anions as well as Cl− anions. Magnetic property measurements show strong antiferromagnetic interaction between nickel(II) ions. 相似文献
12.
Hai-Long Jiang 《Journal of solid state chemistry》2006,179(6):1911-1917
Two new barium zinc selenite and tellurite, namely, BaZn(SeO3)2 and BaZn(TeO3)Cl2, have been synthesized by the solid state reaction. The structure of BaZn(SeO3)2 features double chains of [Zn(SeO3)2]2− anions composed of four- and eight-member rings which are alternatively along a-axis. The double chains of [Zn2(TeO3)2Cl3]3− anions in BaZn(TeO3)Cl2 are formed by Zn3Te3 rings in which each tellurite group connects with three ZnO3Cl tetrahedra. BaZn(SeO3)2 and BaZn(TeO3)Cl2 are wide bandgap semiconductors based on optical diffuse reflectance spectrum measurements. 相似文献
13.
Jie-Ping Fan Wen-Ya Dong Xue-Hong Zhang Jia-Xin Yu Cong-Bo Huang Li-Juan Deng Hui-Ping Chen Hai-Long Peng 《Molecules (Basel, Switzerland)》2022,27(21)
In order to improve the mechanical strength and imprinting efficiency, a novel bovine serum albumin (BSA) molecularly imprinted poly(ionic liquid)/calcium alginate composite cryogel membrane (MICM) was prepared. The results of the tensile test indicated that the MICM had excellent mechanical strength which could reach up to 90.00 KPa, 30.30 times higher than the poly (ionic liquid) membrane without calcium alginate; the elongation of it could reach up to 93.70%, 8.28 times higher than the poly (ionic liquid) membrane without calcium alginate. The MICM had a very high welling ratio of 1026.56% and macropore porosity of 62.29%, which can provide effective mass transport of proteins. More remarkably, it had a very high adsorption capacity of 485.87 mg g−1 at 20 °C and 0.66 mg mL−1 of the initial concentration of BSA. Moreover, MICM also had good selective and competitive recognition toward BSA, exhibiting potential utility in protein separation. This work can provide a potential method to prepare the protein-imprinted cryogel membrane with both high mechanical strength and imprinting efficiency. 相似文献
14.
The thermal annealing process was proposed to purify the pixel regions of a liquid crystal (LC) cell with polymer walls. This technique, based on thermal‐induced phase separation, successfully evicts the residual monomers from the LC volume and significantly improves electro‐optical properties of the polymer‐wall LC devices. The influence of the annealing process on the purity of LC‐rich domain and the electro‐optic properties of a LC cell was explored with a series of experiments. According to the experimental results, the annealing technique is extremely prospective for constructing flexible polymer‐wall LC display applications. 相似文献
15.
铈基催化剂催化氧化燃煤烟气中汞的实验及机理研究 总被引:1,自引:0,他引:1
采用超声波增强的浸渍法合成了CeO2-TiO2催化剂,并采用BET,XRD,XPS等分析手段对催化剂进行了表征。利用固定床反应器,在模拟燃煤烟气条件下研究了CeO2-TiO2催化剂对单质汞的催化氧化行为及机理。结果表明:CeO2-TiO2催化剂在低温范围(150~250°)具有很强的催化氧化汞的能力;最佳的CeO2/TiO2质量比在1.5左右,此时汞的氧化效率可高达90%以上;P25,Evonik TiO2比锐钛矿TiO2更适合做铈基催化剂载体;CeO2-TiO2催化剂上汞的催化氧化符合Langmuir-Hinshelwood机理,即吸附态的汞与其邻近的活性物质反应生成氧化态汞。 相似文献
16.
In this study, we propose a simple strategy based on flow injection and field‐amplified sample‐stacking CE–ESI‐MS/MS to analyze haloacetic acids (HAAs) in tap water. Tap water was passed through a desalination cartridge before field‐amplified sample‐stacking CE–ESI‐MS/MS analysis to reduce sample salinity. With this treatment, the signals of the HAAs increased 300‐ to 1400‐fold. The LODs for tap water analysis were in the range of 10 to 100 ng/L, except for the LOD of monochloroacetic acid (1 μg/L in selected‐ion monitoring mode detection). The proposed method is fast, convenient, and sensitive enough to perform on‐line analysis of five HAAs in the tap water of Taipei City. Four HAAs, including trichloroacetic acid, dichloroacetic acid, dibromoacetic acid, and monobromoacetic acid, were detected at concentrations of approximately 1.74, 1.15, 0.16, and 0.15 ppb, respectively. 相似文献
17.
Young Her Tae-Kyeong Lee Ji Hyeon Ahn Soon Sung Lim Beom-Goo Kang Jung-Seok Park Bora Kim Hyejin Sim Jae-Chul Lee Hyun Sook Kim Tae Heung Sim Hyun Sam Lee Moo-Ho Won 《Molecules (Basel, Switzerland)》2021,26(1)
Since ancient times, various herbs have been used in Asia, including Korea, China, and Japan, for wound healing and antiaging of the skin. In this study, we manufactured and chemically analyzed a novel distillate obtained from a fermented mixture of nine anti-inflammatory herbs (Angelica gigas, Lonicera japonica, Dictamnus dasycarpus Turcz., D. opposita Thunb., Ulmus davidiana var. japonica, Hordeum vulgare var. hexastichon Aschers., Xanthium strumarium L., Cnidium officinale, and Houttuynia cordata Thunb.). The fermentation of natural plants possesses beneficial effects in living systems. These activities are attributed to the chemical conversion of the parent plants to functional constituents which show more potent biological activities. In our current study, the distillate has been manufactured after fermenting the nine oriental medical plants with Lactobacillus fermentum, followed by distilling. We analyzed the chemical ingredients involved in the distillate and evaluated the effects of topical application of the distillate on ultraviolet B (UVB)-induced skin damage in Institute of Cancer Research (ICR) mice. Topical application of the distillate significantly ameliorated the macroscopic and microscopic morphology of the dorsal skin against photodamage induced by UVB radiation. Additionally, our current results showed that topical application of the distillate alleviated collagen disruption and reduced levels of proinflammatory cytokines (tumor necrosis factor alpha and interleukin 1 β expressions) in the dorsal skin against UVB radiation. Taken together, our current findings suggest that the distillate has a potential to be used as a material to develop a photoprotective adjuvant. 相似文献
18.
Dr. Long Jiao Dr. Weijie Yang Dr. Gang Wan Rui Zhang Dr. Xusheng Zheng Dr. Hua Zhou Prof. Dr. Shu-Hong Yu Prof. Dr. Hai-Long Jiang 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2020,132(46):20770-20776
Single-atom catalysts (SACs) are of great interest because of their ultrahigh activity and selectivity. However, it is difficult to construct model SACs according to a general synthetic method, and therefore, discerning differences in activity of diverse single-atom catalysts is not straightforward. Herein, a general strategy for synthesis of single-atom metals implanted in N-doped carbon (M1-N-C; M=Fe, Co, Ni and Cu) has been developed starting from multivariate metal–organic frameworks (MOFs). The M1-N-C catalysts, featuring identical chemical environments and supports, provided an ideal platform for differentiating the activity of single-atom metal species. When employed in electrocatalytic CO2 reduction, Ni1-N-C exhibited a very high CO Faradaic efficiency (FE) up to 96.8 % that far surpassed Fe1-, Co1- and Cu1-N-C. Remarkably, the best-performer, Ni1-N-C, even demonstrated excellent CO FE at low CO2 pressures, thereby representing a promising opportunity for the direct use of dilute CO2 feedstock. 相似文献
19.
20.
摘 要:基于第一性原理的计算方法,建立了本征石墨烯、空位石墨烯及钇( Y)掺杂空位石墨烯模型,并计算了CO、NO在三类石墨烯表面的吸附过程. 从表面能、吸附结构、吸附能和态密度四个方面进行分析讨论,研究掺杂Y对CO、NO气体吸附性能的影响. 结果表明:CO、NO与本征石墨烯之间的吸附为弱的物理吸附,掺杂Y后增强了材料表面对CO、NO的吸附效果,最大吸附能分别为7.414eV、6.702eV,属于化学吸附;掺杂Y使空位石墨烯费米能级附近有了更多的活跃电子,其吸附NO后体系由半金属转变为金属特性,该特性能为开发更加优良的石墨烯气敏材料提供理论支持. 相似文献