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131.
The hydrolysis of lithium hydride (LiH) is a promising technique for the supply of hydrogen. LiH can be stored in sealed tanks or cartridges of ∼6% mass effective hydrogen capacity. However, the lack of an efficient recycling method for the byproduct lithium hydroxide (LiOH) has been a limitation to its use. Here, we propose and demonstrate a recycling process based on the hot melt electrolysis of a LiOH–LiCl eutectic mixture at 380 °C. The electrolysis activation potential was measured at 3.08 V. Lithium production was observed around the cathode using differential scanning calorimetry (DSC) and cyclic voltametry. Current efficiency was estimated 37.9%, and the absence of LiCl decomposition was confirmed.  相似文献   
132.
Vibrio parahaemolyticus is a marine bacterium causing foodborne disease. Occurrence of the bacterium was investigated in six species of edible crustaceans available from markets in mainland China. The bacterium was detected in 22 of 45 whole-body, shell, and feces samples, including mitten crabs, which are supposed to be produced in freshwater ponds. The mean densities ranged from 2.8 log CFU/g in mitten crabs (Eriocheir sinensis) to 5.1 CFU/g in giant tiger prawns (Penaeus monodon). In hemolymph and muscle samples collected axenically, V. parahaemolyticus was detected in all of the prawns at a mean density of 2.6 log most probable number (MPN)/g, in two of five striped stone crabs (Charybdis feriatus) at a mean density of 1.1 log MPN/ml, and two of five mangrove mud crabs (Scylla serrata) at a mean density of 1.3 log MPN/ml. When six mitten crabs were collected from two freshwater ponds in China and were examined, V. parahaemolyticus was not detected. It seemed that cross-contamination occurred among live crustaceans at the markets. The results suggest that proper handling, storage, and cooking of these crustaceans will be necessary to lessen the risk of foodborne illness from V. parahaemolyticus.  相似文献   
133.
Vibrio vulnificus is a naturally occurring estuarine bacterium often associated with disease such as septicemia in humans following consumption of raw and lightly cooked seafood. In China and neighboring countries, rapid economic growth has encouraged increased consumption of seafood, and dietary habits are changing, with more people eating raw fish. In this study, the prevalence of V. vulnificus was investigated in 48 samples from 11 species of live seafood available from markets in coastal cities of China. The bacterium was detected in four of four razor clam samples, in seven of seven giant tiger prawn samples, and in five of nine mantis shrimp samples. The bacterium was also found in water samples of the prawn aquaria at the markets. The maximum level of V. vulnificus was 3.4 log CFU/g in the razor clam samples and 4.9 log CFU/g in the prawn samples by a direct spreading method. Differential bacterial counts on the prawn body revealed that most of the bacteria were found on the shells (exoskeletons), with very few in the edible muscle. However, dense populations can be found in the intestines. Biochemical tests indicated that the isolates of V. vulnificus were biotype 1 strain, which is pathogenic to humans. These isolates were susceptible to ampicillin, penicillin, kanamycin, streptomycin, and erythromycin. These results suggest that V. vulnificus is a potential health hazard to humans in cities consuming and handling live shellfish, especially giant tiger prawns.  相似文献   
134.
Continuous erythropoietin receptor activator (CERA) seems to maintain a stable hemoglobin (Hb) level because its half-life is longer than darbepoetin α (DA). Twenty chronic kidney disease (CKD) patients at the pre-dialysis stage who had been administered DA for over 24 weeks were randomly assigned to receive subcutaneous CERA or DA once every four weeks during 48 weeks. In both groups, the rate of achievement of target Hb level changed from 70% to 100% in weeks 0 to 48, with no significant difference between the groups. Compared with week 0, the Hb level was significantly increased from week 24 in the DA group and from week 8 in the CERA group. In addition, the reticulocyte count was significantly increased from week 4 in the CERA group compared with the DA group. There was no significant difference in the levels of estimated glomerular filtration rate and iron status between both groups. Because of the small number of patients in this study, only limited conclusions can be drawn. However, the results suggest that subcutaneous administration of DA or CERA once every four weeks to predialysis patients has similar effects on achievement of target Hb levels.  相似文献   
135.
利用金相和SEM,XRD,DSC和VSM研究了Co含量x对Ni52Ga28Fe20-xCox合金马氏体相变和铁磁性的影响。结果表明:x≤6%时(原子分数,下同),Co代替Fe显著提高合金的马氏体相变温度,每1%Co可以使马氏体相变温度提高50K~60K,但对Curie点的影响不大。淬火温度从1423K降低到773K对马氏体相变温度的影响不大,但使Curie点提高20K-30K,其原因是母相的B2→L21转变导致的有序化程度提高。粉末试样X射线衍射发现1423K和773K2种温度处理后都只出现L10(2M)晶体结构类型的马氏体,并且合金粉末化后降低了马氏体相变温度和增加了γ相的析出,但块状Ni52Ga28Fe17Co3合金773K淬火后为14M型马氏体。  相似文献   
136.
Artificial Life and Robotics - Percutaneous coronary intervention (PCI) is mainly used in the treatment of stenosis of the coronary arteries of the heart characteristic of coronary artery disease,...  相似文献   
137.
Chemical ligation reaction of DNA is useful for the construction of long functional DNA using oligonucleotide fragments that are prepared by solid phase chemical synthesis. However, the unnatural linkage structure formed by the ligation reaction generally impairs the biological function of the resulting ligated DNA. We achieved the complete chemical synthesis of 78 and 258 bp synthetic DNAs via multiple chemical ligation reactions with phosphorothioate and haloacyl-modified DNA fragments. The latter synthetic DNA, coding shRNA for luciferase genes with a designed truncated SV promoter sequence, successfully induced the expected gene silencing effect in HeLa cells.  相似文献   
138.
Metallurgical and Materials Transactions A - Herein, the behavior associated with strain-induced abnormally large grains in superalloy 718 was investigated using compression testing and subsequent...  相似文献   
139.
Recently, the noncontact conveyance methods that are applied magnetic levitation techniques have been studied in many institutes. In this paper, from the view point of practical use, the authors construct a magnetic levitation system without using gap sensors which have been essential for the conventional magnetic levitation of thin steel plates. This system adopts both current sensors and Hall‐effect sensors in place of the gap sensors. In addition, we consider the peculiar inductance characteristics of magnetic levitation for a thin steel plate. Moreover, we conduct the levitation, guidance, conveyance and disturbance experiments.  相似文献   
140.
The charge density produced by streamers on an insulator surface in SF6 has been investigated by using a probe method with a high-speed temporal resolution. Concentric circular probes, which also act as a plane electrode, are used in this probe method. Probe signals are observed oscilloscopically and converted into the charge densities through a numerical calculation. This method reveals the charge distribution before a disturbance caused by the “back discharge.” The charge density thus obtained ranges from several nC/cm2 up to about 60 nC/cm2. The density depends on the pressure, voltage height and the position of the streamer. The electric field on the insulator is analyzed numerically taking into account the surface charge. The internal electric field of the streamer is found to be 40 ~ 50 kV/cm · atm when the streamer ceases its propagation. However, it partly exceeds the critical one (89 kV/cm · atm) during the propagation.  相似文献   
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