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991.
Marieke M. Hoog Antink Lisa Röpke Julia Bartels Christian Soltmann Andreas Kunzmann Kurosch Rezwan Stephen Kroll 《Ceramics International》2018,44(14):16561-16571
The growing demand for stony corals as ornamental aquarium animals requires defined aquacultural breeding strategies. For the sexual propagation of corals, material substrates are needed, that attract larvae and support their settlement and development. In this study, five types of highly porous ceramic materials were developed following the example of coral skeleton. The applicability of these settlement substrates was tested using larvae of the stony coral Pocillopora damicornis. Partial sintering of pressed clay pellets, freeze casting of clay and alumina-mullite based slurries and direct foaming of high alkane phase emulsified suspensions (HAPES) using alumina were employed. By the addition of mm-sized spherical polystyrene beads as sacrificial templates during freeze casting (alumina-mullite), superficial pores in the size of the larvae were created. The inorganic substrates featured open porosities between 35% (pressed clay) and 83% (foamed alumina), pore sizes ranging from nm to mm-scale and pore morphologies dominated by interparticle porosity (pressed), lamellar pores (freeze casting) and cellular pore types (direct foaming). The ceramic substrates were incubated in artificial sea water for 3 months to induce necessary biofilm formation and algae growth. Afterwards, individual substrates were exposed to 5 coral larvae, and their settlement behavior was monitored over 14 days. At the end of this period, all ceramic materials were successfully accepted as settlement substrates, with a mean settlement rate of 46.2%, and no significant differences between the substrate types. On samples with large surface superficial pores, a significantly reduced survival of settled larvae (79%) compared to the other porous materials (93–98%) was determined, suggesting a non-ideal surface topography. While alumina foam samples (HAPES) exhibit the most promising results in terms of settlement and survival of larvae, clay-based substrates provide a more economic solution for the sexual propagation of corals in aquaculture. 相似文献
992.
Dr. Ferenc Zsila 《Chembiochem : a European journal of chemical biology》2018,19(9):895-901
Inhalational anesthetics are routinely employed in clinical practice to accomplish general anesthesia. Concerns have recently emerged regarding the deleterious impact of these volatile agents on cognitive performance, immune functions, and tumor recurrence and metastasis. These agents have been shown to modify the gene‐expression pattern as well as cell signaling in tumor cells, but the underlying molecular mechanisms remain a matter of conjecture. Regulatory/signaling proteins either of cytosolic or membrane origin abundantly contain intrinsically disordered sequences, the conformational pliability of which is pivotal in their biological functions. It is well known that chloroform (an anesthetic itself), trifluoroethanol, hexafluoroisopropanol, and related haloalcohols markedly affect the structure of disordered proteins and protein regions by inducing folding, misfolding, or even aggregation. Taking into consideration the physicochemical similarities and protein interaction modes of these volatile solvents and inhaled anesthetics, it is postulated that administration of these drugs can also modify the secondary structure of disordered protein segments. Accordingly, pharmacological effects of anesthetics may, at least in part, be mediated by conformational perturbations of intrinsic disorder‐based regulatory protein networks of cells. 相似文献
993.
MAO Jianzhao GAO Huihui XUE Runping YANG Chen LIU Pengqing XU Jianjun CHEN Sheng JIANG Mengjin 《储能科学与技术》2019,8(2):304-310
以硫酸肼(HS)、对苯二甲酸(TPA)、4,4'-联苯醚二甲酸(DPE)为单体,发烟硫酸做溶剂和脱水剂一步合成了一系列不同TPA和DPE单体配比的磺化聚芳噁二唑(SPOD),再通过氢氧化锂中和得到聚芳噁二唑磺酸锂(Li-SPOD)聚合物电解质,采用浇铸成膜法制得Li-SPOD电解质膜,研究改变TPA和DPE两种单体配比对Li-SPOD结构及性能的影响。结果表明,几种不同单体配比均能实现在聚合过程中一步得到SPOD,磺酸基团接枝在DPE结构的苯环上,并且可以达到理论接枝量;同时Li-SPOD电解质膜的聚集态结构差异很小;热性能的表现均非常优异,初始热分解温度都在450 ℃以上;力学性能随DPE单体含量的增加稍有下降但依然保持在较高的水平;电导率约为10-5S/cm级别,随DPE含量增加而逐渐降低;Li-SPOD固态电解质电化学稳定性较好,对锂稳定电化学窗口均在4.0 V以上。 相似文献
994.
995.
Pedro García-Serrano Concepción Romero Pedro García-García Manuel Brenes 《International Journal of Food Science & Technology》2021,56(2):919-926
The preservation of olives intended for processing as black ripe olives must be done in a salt-free environment although it involves the use of calcium addition to retard olive softening. Calcium chloride and calcium lactate were added by up to 1600 mg Ca L−1 (i) in the preservation liquid of olives before darkening and (ii) in the cover packing brine. The highest texture and calcium absorption were found in the latter case. In addition, the sensory characteristics of the final product were not affected by the use of any of the calcium salts studied at concentrations of up to 1600 mg Ca L−1. Calcium chloride and calcium lactate can be employed to obtain higher texture and calcium content in black ripe olives, although it is advisable to add the cation to the cover packing brine of pitted olives rather than to the preservation liquid. 相似文献
996.
《Intermetallics》2016
This study focuses on the fracture characteristics of Cu6Sn5 and Cu3Sn micro beams under micro-cantilever bending tests. These micro beams were fabricated by focused ion beam (FIB) from the Sn-rich solder joints aged at 175 °C for 1132.5 h, and then tested using a nanoindenter with a flat tip. Experimental results show that both Cu6Sn5 and Cu3Sn micro beams underwent elastic deformation before their failure. From fractographic analysis, both cleavage fracture and intergranular fracture can be identified from the tested Cu6Sn5 micro beams, while only intergranular fracture was found in Cu3Sn micro beams. Furthermore, based on the experimental results, finite element analysis was carried out to evaluate the tensile fracture strength and strain of Cu6Sn5 and Cu3Sn micro beams. For Cu6Sn, the tensile fracture strength was estimated to be 1.13 ± 0.04 Pa and the average tensile strain was 0.01. The tensile fracture strength and strain of Cu3Sn were evaluated to be 2.15 ± 0.19 GPa and 0.016, respectively. 相似文献
997.
WO3 membrane-encapsulated layered LiNi0.6Co0.2Mn0.2O2 cathode material for advanced Li-ion batteries
Guowen Song Hui Zhong Yanyang Dai Xiangyang Zhou Juan Yang 《Ceramics International》2019,45(6):6774-6781
Despite Nickel-rich materials have all the advantages of high capacity, long cycle life and low cost, there is still a disadvantage that the capacity decreases rapidly as the number of cycles increases. In order to solve this problem, WO3 was uniformly coated on the surface of LiNi0.6Co0.2Mn0.2O2 cathode materials by wet coating, and its cycling performance was greatly improved with the higher capacity. The coated materials were analyzed by X-ray diffraction(XRD), Scanning electron microscope (SEM), high resolution Transmission electron microscopy (TEM) and X-ray photoelectron spectroscopy(XPS). The results showed that the coating thickness was around 3.15?nm, and some tungsten ions were doped into the lattice of the near surface area of the LiNi0.6Co0.2Mn0.2O2 material. In addition, the results of charge-discharge test showed that 1?wt%WO3 coating LiNi0.6Co0.2Mn0.2O2 had the best performance, and delivered a discharge capacity of 140 mAh g?1 (the capacity retention rate is 84.8%) in the potential interval of 2.8–4.3?V at 1?C (1?C?=?165?mA?g?1) after 200 cycles, while the bare cathode material only delivered a discharge capacity of 120 mAhg?1 (the capacity retention rate is 75%). The phenomenon indicates that the WO3 coating plays a role in inhibiting the harmful side reactions between the cathode material and the electrolyte, improving the electrochemical and structure stability of LiNi0.6Co0.2Mn0.2O2 cathode materials. 相似文献
998.
钻孔灌注桩在岩溶作用严重地区施工时,给运营线铁路的正常运行安全带来很大的安全隐患。根据不同的地质情况,本文通过具体的工程实例,介绍了片石黏土填塞法和水泥注浆法在钻孔灌注桩岩溶地区施工中的运用,从两种处理方案的选择方面做详细分析并给予处理解决措施,为以后相关工程提供借鉴。 相似文献
999.
《分离科学与技术》2012,47(11):2471-2490
Abstract Significant performance differences in the separation of desamido-insulin from insulin and of amitriptyline from imipramine have been found for five, macroscopically similar, preparative C18 silica materials. Structure-performance relations have been used to understand this difference. Physical measurements on the unpacked silica gels as well as chromatographic measurements have been carried out. The latter measurements comprise: hydrophobicity, metal impurity, steric selectivity and silanol activity. The performance difference could not be explained by the difference in hydrophobicity, steric selectivity or metal impurity between the materials. Instead a correlation between the silanol ion exchange activity and the selectivity could be found. The highest performance was found under conditions where the silanol groups have a moderate activity. For the separations considered in this work, the silanol groups have a beneficial effect. 相似文献
1000.
《分离科学与技术》2012,47(15):2507-2515
ABSTRACTIn present study, illite flotation behavior with Cetyl Trimethyl Ammonium Chloride (CTAC) as the collector has been studied to investigate the effects of its residual concentration on froth stability and flotation. Results showed that, with increasing conditioning time, the residual concentration (frother concentration) and froth height decreased simultaneously, while the adsorbed amount (particle hydrophobicity) increased. Increasing CTAC conditioning time decreased the residual concentration in solutions, resulting in poor froth stability and flotation recovery at high pH; the adsorption rate of CTAC on illite surface was relatively high at higher pH due to strong electrostatic mechanism, making CTAC residual concentration decrease. 相似文献