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981.
982.
对具有复合介质的感应电炉的电磁场理论进行了研究,导出工程实用的电参数计算公式,计算分析目前常用的两种典型复合介质熔炼炉的电参数,其结果更符合复合介质感应熔炉的实际。 相似文献
983.
HP1-EDM电火花加工喷孔机床的应用 总被引:5,自引:1,他引:5
介绍了瑞士HP1-EDM电火花喷油嘴喷孔加工机床的结构原理、特点、加工精度及各种因素对加工精度的影响,并叙述了对该机床应用的体会。从应用中体会到,在加工喷孔时要特别注意U轴的正确使用,否则将对孔的尺寸、加工时间等均会带来影响。 相似文献
984.
Lianqi Zhang Hideyuki Noguchi Decheng Li Takahisa Muta Xiaoqing Wang Masaki Yoshio Izumi Taniguchi 《Journal of power sources》2008
On the basis of extreme similarity between the triangle phase diagrams of LiNiO2–LiTiO2–Li[Li1/3Ti2/3]O2 and LiNiO2–LiMnO2–Li[Li1/3Mn2/3]O2, new Li–Ni–Ti–O series with a nominal composition of Li1+z/3Ni1/2−z/2Ti1/2+z/6O2 (0 ≤ z ≤ 0.5) was designed and attempted to prepare via a spray-drying method. XRD identified that new Li–Ni–Ti–O compounds had cubic rocksalt structure, in which Li, Ni and Ti were evenly distributed on the octahedral sites in cubic closely packed lattice of oxygen ions. They can be considered as the solid solution between cubic LiNi1/2Ti1/2O2 and Li[Li1/3Ti2/3]O2 (high temperature form). Charge–discharge tests showed that Li–Ni–Ti–O compounds with appropriate compositions could display a considerable capacity (more than 80 mAh g−1 for 0.2 ≤ z ≤ 0.27) at room temperature in the voltage range of 4.5–2.5 V and good electrochemical properties within respect to capacity (more than 150 mAh g−1 for 0 ≤ z ≤ 0.27), cycleability and rate capability at an elevated temperature of 50 °C. These suggest that the disordered cubic structure in some cases may function as a good host structure for intercalation/deintercalation of Li+. A preliminary electrochemical comparison between Li1+z/3Ni1/2−z/2Ti1/2+z/6O2 (0 ≤ z ≤ 0.5) and Li6/5Ni2/5Ti2/5O2 indicated that charge–discharge mechanism based on Ni redox at the voltage of >3.0 V behaved somewhat differently, that is, Ni could be reduced to +2 in Li1+z/3Ni1/2−z/2Ti1/2+z/6O2 while +3 in Li6/5Ni2/5Ti2/5O2. Reduction of Ti4+ at a plateau of around 2.3 V could be clearly detected in Li1+z/3Ni1/2−z/2Ti1/2+z/6O2 with 0.27 ≤ z ≤ 0.5 at 50 °C after a deep charge associated with charge compensation from oxygen ion during initial cycle. 相似文献
985.
2-Acetyl-1-pyrroline: A key aroma component of aromatic rice and other food products 总被引:1,自引:0,他引:1
2-Acetyl-1-pyrroline is an aroma compound that gives aromatic rice its characteristic flavor. This compound either is present naturally in various food sources or is generated during certain processing methods, as reported in a number of studies. This review focuses on several sources of 2-acetyl-1-pyrroline, including aromatic rice, and the factors, including chemical and genetic parameters, affecting the formation of 2-acetyl-1-pyrroline. Extensive work has been conducted on the agricultural parameters, postharvest processing, storage, and cooking methods, influencing the concentrations of 2-acetyl-1-pyrroline in different food commodities. This article is an attempt to emphasize the importance of this compound in the food industry as a major aroma compound. 相似文献
986.
Shahira Said Aly Tsuyoshi Imai Mohamed Salah Hassouna Diem-Mai Kim Nguyen Takaya Higuchi Ariyo Kanno Koichi Yamamoto Rinji Akada Masahiko Sekine 《International Journal of Hydrogen Energy》2018,43(10):5300-5313
The ability of Clostridium butyricum RAK25832 to use casamino acids as a nitrogen source was investigated. Strain RAK25832 showed the capacity to utilize different types of carbon sources. With glucose as a carbon source (10 g/L), the preferred final concentration of casamino acids was 26.67 g/L, with a cumulative hydrogen production, production rate, and yield of 2505 mL H2/L, 160 mL/h, and 1.81 mol H2/mol glucose, respectively. Eighteen metal elements were screened to identify the most important metals for biohydrogen production, and four elements were optimized. The optimal medium composition was MgCl2·6H2O (0.1 g/L), K2HPO4·3H2O (6.67 g/L), NaHCO3 (2.6 g/L), and FeCl2·4H2O (0.002 g/L). Vitamin supplementation of the medium showed no significant effect on hydrogen production. Under the optimized conditions, cumulative hydrogen production reached 3074 mL H2/L. This is the first study to demonstrate the use of casamino acids as a nitrogen source by C. butyricum. 相似文献
987.
988.
Pramodkumar D. Jadhav Yang Zuo Youn Young Shim Jianheng Shen Martin J. T. Reaney Ning Zhang Yong Wang 《International Journal of Food Science & Technology》2018,53(8):1972-1982
Linusorbs (LOs; a.k.a. cyclolinopeptides) are naturally occurring orbitides derived from flaxseed. These compounds consist of 8–10 amino acid residues, which are linked via an N ‐ to C‐terminal peptide bond with molecular masses of approximately 1 kDa. The LO circular structure makes them candidates for metal binding studies. Flaxseed extracts are known to suppress Pb and Cd toxicity. Hence, four metal salts surveyed include Zn(CH3COO)2, ZnSO4, Pb(CH3COO)2 and Cd(NO3)2 with pure LOs 1–5 . Proton NMR spectra indicated interaction of LOs with metal salts in solution and were used to determine impacts of methionine oxidation on interactions with metal ions. The methyl group of methionine S,S ‐ dioxide of related LOs did not show the same shift in the presence of Zn(CH3COO)2 and Pb(CH3COO)2 observed in their methionine S ‐ oxide analogues. Metal complexes were observed forming at 10?2 m to 10?4 m but not at lower concentrations (10?5 m to 10?8 m ). Mass spectrometry data confirmed that metal binding strength varied by metal in the order Zn(CH3COO)2<Pb(CH3COO)2<ZnSO4<Cd(NO3)2. 相似文献
989.
Dejing Chen Jingyuan Sun Weixue Dong Yixiao Shen Zhimin Xu 《International Journal of Food Science & Technology》2018,53(10):2335-2341
The effects of polysaccharides, theaflavins, thearubigins and theabrownin fractions of Zijuan tea on α‐glucosidase and blood glucose level and intolerance of hyperglycaemic mice were evaluated. The polysaccharides or theaflavins fraction exhibited greater inhibition rate of α‐glucosidase than acarbose positive control, thearubigins fraction or theabrownin fraction. The four fractions were delivered to the treatment mice through oval gavage each day for 15 days. The mice in polysaccharides and theaflavins high‐ and low‐dose and theabrownin high‐dose treatments significantly lowered their blood glucose levels while all the treatment mice gained body weight. The mice in polysaccharides, theaflavins and theabrownin high‐ and low‐dose treatments had greater glucose tolerance as well. Thus, the theaflavins and polysaccharides fractions of Zijuan tea effectively moderated the complications of hyperglycaemic mice. The lower effectiveness of thearubigins and theabrownin fractions may be caused by the highly polymerised polyphenolics which decreased their accessibility to α‐glucosidase and digestibility in mice. 相似文献
990.
Sherif M. Sharroush 《International Journal of Electronics》2018,105(12):2009-2032
As well known by computer architects, the performance gap between the processor and the memory has been increasing over the years. This causes what is known as the memory wall. In order to alleviate the problem, a novel fast readout scheme is proposed in this article for the single-transistor single-capacitor dynamic random-access memory (1T-1C DRAM) cells. The proposed scheme works in the current domain in which the difference between the discharging rates of the bitline in the cases of ‘1’ and ‘0’ readings is detected. The proposed scheme is analysed quantitatively and compared with the conventional readout scheme. It is verified by simulation adopting the 45 nm CMOS Berkley predictive-technology model (BPTM) and shows 44 and 7.7% reductions in the average read-access and cycle times, respectively, as compared to the conventional readout scheme. It is also shown that the power is saved according to the proposed scheme if the probability of occurrence of ‘0’ storage exceeds 66.7%. This minimum value can be alleviated, however, at the expense of a smaller saving in the average read-access time. The impacts of process variations and technology scaling are also taken into account. 相似文献