北京周边地区低盐固态制曲过程中酶系活力的变化

通过对北京周边地区4个低盐固态酱油厂家制曲过程进行跟踪监控,测定分析其制曲过程中中性、酸性和碱性蛋白酶、淀粉酶、纤维素酶、谷氨酰胺酶和亮氨酸氨肽酶活力的变化.结果表明,即使是同种工艺不同厂家之间的各个酶活力存在显著性差异,同时现有工艺不能产生丰富且较高酶活的酶系.     

Multi-locus genotyping of bottom fermenting yeasts by single nucleotide polymorphisms indicative of brewing characteristics

Yeast plays a capital role in brewing fermentation and has a direct impact on flavor and aroma. For the evaluation of competent brewing strains during quality control or development of novel strains it is standard practice to perform fermentation tests, which are costly and time-consuming. Here, we have categorized DNA markers which enable to distinguish and to screen brewing strains more efficiently than ever before. Sequence analysis at 289 loci in the genomes of six bottom fermenting Saccharomyces pastorianus strains revealed that 30 loci contained single nucleotide polymorphisms (SNPs). By determining the nucleotide sequences at the SNP-loci in 26 other S. pastorianus strains and 20 strains of the top fermenting yeast Saccharomyces cerevisiae, almost all these strains could be discriminated solely on the basis of the SNPs. By comparing the fermentative phenotypes of these strains we found that some DNA markers showed a strong association with brewing characteristics, such as the production of ethyl acetate and hydrogen sulphide (H2S). Therefore, the DNA markers we identified will facilitate quality control and the efficient development of brewing yeast strains.     

Effect of pre-deformation on the precipitation process and magnetic properties of Fe–Cu model alloys

The effect of pre-deformation on the precipitation process and magnetic properties of Fe–Cu model alloys was investigated. These specimens simulate irradiation embrittlement of nuclear reactor pressure vessel (RPV) steels. Fe–1 wt%Cu alloys with and without pre-deformation in solid-state solution were thermally aged at 773 K for various times and the evolution of hardness, conductivity, and microstructure were investigated. Pre-deformation enhanced Cu precipitation and caused precipitation at dislocations. The coercive force tended to decrease for the pre-deformed specimen and the underlying mechanism is discussed. The results obtained are related to the magnetic characteristics of irradiated RPV steels.     

HRP-2W: A humanoid platform for research on support behavior in daily life environments

We introduce a concept of a real-world-oriented humanoid robot that can support humans’ activities in daily life. In such environments, robots have to watch humans, understand their behavior, and support their daily life tasks. In particular, these robots must be capable of such real-world behavior as handling tableware and delivering daily commodities by hand. We developed a humanoid robot, HRP-2W, which has an upper body of HRP-2 [K. Kaneko, F. Kanehiro, S. Kajita, H. Hirukawa, T. Kawasaki, M. Hirata, K. Akachi, T. Isozumi, Humanoid Robot HRP-2, in: Proceedings of the 2004 IEEE International Conference on Robotics & Automation, 2004, pp. 1083–1090] and a wheel module instead of legs, as a research platform to fulfill this aim. We also developed basic software configuration in order to integrate our platform with other research groups. Through experiments, we demonstrated the feasibility of the humanoid robot platform and the potential of the software architecture.     

Study on plastic deformation in cone-type rotary piercing process using model piercing mill for modeling clay

Pierce rolling is the rolling performed first in the production of seamless pipes. In both barrel-type rotary piercing and cone-type rotary piercing, the material is subjected to shearing deformation due to rotary forging. Only a few experimental studies on cone-type rotary piercing have been conducted to obtain the strain components. This paper describes the plastic deformation in the cone-type rotary piercing process using a model piercing mill with modeling clay. First, the model piercing mill is designed and fabricated, and then the effects of the cross-angle and feed angle on the strain components are clarified. It was found that, when the cross-angle is approximately 20°, the longitudinal section of the specimen before rolling becomes the longitudinal section of the specimen after rolling, irrelevant of the feed angle.     

Crystallization behavior of polypropylene filled with surface-modified calcium carbonate

Polypropylene (PP) and calcium carbonate (CaCO₃) were mixed in a two-roll mill. The mixed compounds were molded on the plate by using a compression press heater. To improve the affinity of the relation between CaCO₃ and the PP matrix, we modified the CaCO₃ surface through chemical reaction with alkyl dihydrogen phosphates. The CaCO₃ content and size modification affected the crystallization behavior of the filled PP composites. The crystallization temperature in the nonisothermal crystallization process increased with the increase of CaCO₃ content and the decrease of CaCO₃ size. The crystallization temperature revealed the function of log (1 + T_s) (T_s, total surface area of CaCO₃) irrespective of CaCO₃ content and size for modified and unmodified systems, respectively. The shoulder or double crystallization peak of PP composites is recognized for the unmodified system (particle sizes: 1.0 and 4.5 μm).     

Synthesis and blend morphology of BA/BC-type binary graft copolymers composed of polyelectrolyte trunks

Poly(α-methylstyrene) (PMS) macromonomer having one vinylbenzyl group per polymer chain was prepared by the couplings of living PMS with p-chloromethylstyrene (CMS). Subsequently, well-defined poly[acrylic acid (AA)-g-α-methylstyrene (MS)] and poly[4-vinylpyridine (4VP)-g-MS] graft copolymers composed of polyelectrolyte trunks were prepared by radical copolymerization of PMS macromonomer with AA and 4VP monomers, respectively. Binary poly(AA-g-MS)/poly(4VP-g-MS) or poly[AA · triethyl amine (Et₃N) salt-g-MS)/poly(4VP-g-MS) graft copolymer blend films were cast from a benzene/methanol mixture. The morphological results of binary graft copolymer blends are discussed with respect to three-phase separated structures.     

Asymmetric Intramolecular Ene Reaction Catalyzed by a Chiral Titanium Reagent and Synthesis of (—)-ε-Cadinene

A highly diastereo- and enantio-selective intramolecular ene reaction was developed by employing a chiral titanium reagent generated in situ from TiCl₂(OPrⁱ)₂ and a tartrate-derived chiral 1,4-diol. This reaction afforded masked cyclohexanone and cyclopentanone derivatives with high optical purities which were synthetically useful chiral building blocks. From the intramolecular ene product (—)-ε-cadinene was synthesized by the use of the newly developed intramolecular Michael reaction.