First observation of the decay B@?_s⁰→D⁰K^@?0 and a measurement of the ratio of branching fractions B(B@?_s⁰→D⁰K^@?0)B(B@?⁰→D⁰ρ⁰)

LHCb Collaboration,Aaij, R.,Abellan Beteta, C.,Adeva, B.,Adinolfi, M.,Adrover, C.,Affolder, A.,Ajaltouni, Z.,Albrecht, J.,Alessio, F.,Alexander, M.,Alkhazov, G.,Alvarez Cartelle, P.,Alves, A.A.,Amato, North-Holland Pub. Co 2011 Physics letters: B Vol.706 No.1

The first observation of the decay B@?<SUB>s</SUB><SUP>0</SUP>→D<SUP>0</SUP>K<SUP>@?0</SUP> using pp data collected by the LHCb detector at a centre-of-mass energy of 7 TeV, corresponding to an integrated luminosity of 36 pb<SUP>-1</SUP>, is reported. A signal of 34.4+/-6.8 events is obtained and the absence of signal is rejected with a statistical significance of more than nine standard deviations. The B@?<SUB>s</SUB><SUP>0</SUP>→D<SUP>0</SUP>K<SUP>@?0</SUP> branching fraction is measured relative to that of B@?<SUP>0</SUP>→D<SUP>0</SUP>ρ<SUP>0</SUP>: B(B@?<SUB>s</SUB><SUP>0</SUP>→D<SUP>0</SUP>K<SUP>@?0</SUP>)B(B@?<SUP>0</SUP>→D<SUP>0</SUP>ρ<SUP>0</SUP>)=1.48+/-0.34+/-0.15+/-0.12, where the first uncertainty is statistical, the second systematic and the third is due to the uncertainty on the ratio of the B<SUP>0</SUP> and B<SUB>s</SUB><SUP>0</SUP> hadronisation fractions.

Enhanced strength and ductility in particulate-reinforced aluminum matrix composites fabricated by flake powder metallurgy

Kai, X.Z.,Li, Z.Q.,Fan, G.L.,Guo, Q.,Xiong, D.B.,Zhang, W.L.,Su, Y.S.,Lu, W.J.,Moon, W.J.,Zhang, D. Elsevier Sequoia 2013 Materials science & engineering. properties, micro Vol.587 No.-

Reinforcement agglomeration always leads to severe stress concentration and porosity, which is detrimental to the deformation ability and mechanical properties of particulate-reinforced metal matrix composites. In this study, uniform distribution of 32vol%B<SUB>4</SUB>C has been achieved in B<SUB>4</SUB>C/Al composite by means of flake powder metallurgy (Flake PM), in which flake Al powder is used as the starting material. The flake Al powder exhibits higher apparent volume than spherical powders of the same mass, and thus can provide more space to accommodate the B<SUB>4</SUB>C particles. Therefore, compared with conventional PM, Flake PM can lead to more uniform distribution of B<SUB>4</SUB>C particles in the composite powder as well as in the consolidated composite. Meanwhile, the flake Al powder has a nano skin of Al<SUB>2</SUB>O<SUB>3</SUB>, which could be fractured and dispersed inside the fine matrix grains during consolidation, and were found to induce a higher normalized strain hardening rate for the composite during deformation. As a result, the Flake PM 32vol%B<SUB>4</SUB>C/Al composite exhibits an ultimate tensile strength of 305MPa and a uniform elongation of 6.6%, 63% stronger and 13% more ductile than its counterpart fabricated by conventional PM.

Search for the decayB0→ϕγ

King, Z.,Pal, B.,Schwartz, A. J.,Adachi, I.,Aihara, H.,Al Said, S.,Asner, D. M.,Atmacan, H.,Aushev, T.,Ayad, R.,Bakich, A. M.,Behera, P.,Bhardwaj, V.,Bhuyan, B.,Biswal, J.,Bobrov, A.,Bozek, A.,Browder American Physical Society 2016 Physical Review D Vol.93 No.11

<P>We have searched for the decay B-0 -> phi gamma sing the full Belle data set of 772 x 10(6) B (B) over bar pairs collected at the gamma(4S) resonance with the Belle detector at the KEKB e(+)e(-) collider. No signal is observed, and we set an upper limit on the branching fraction of B(B-0 -> phi gamma) < 1.0 x 10(-7) at the 90% confidence level. This is the most stringent limit on this decay mode to date.</P>

Influences of Enzyme Complex Supplementation on Growth, Ileal and Apparent Fecal Digestibility and Morphology of Small Intestine in Pigs

Kim, B.G.,Tian, J.Z.,Lim, J.S.,Kil, D.Y.,Jeon, H.Y.,Chung, Y.K.,Kim, Y.Y. Asian Australasian Association of Animal Productio 2004 Animal Bioscience Vol.17 No.12

A total of 140 weaning pigs were used to determine the effects of digestive enzyme supplementation to corn-soybean meal diets on growth performance, physiological changes of small intestine, microorganisms and pH in the gastrointestinal tract. Two kinds of enzyme complex (A, B) were used in this experiment. Pigs were allotted in a completely random design (CRD) to five replicates with four pigs per pen. Diets and water were provided for ad libitum consumption. Treatments included 1) Control: without enzyme supplementation, 2) Enzyme A 0.05%, 3) Enzyme A 0.10%, 4) Enzyme A 0.15%, 5) Enzyme B 0.05%, 6) Enzyme B 0.10%, 7) Enzyme B 0.15% in the diets. A total of 24 crossbred barrows 25.78${\pm}$0.55 kg BW fitted with simple ileal T-cannulas were used to evaluate the effect the enzyme addition on the nutrient digstibility. Pigs were allotted 4 treatments (No enzyme, enzyme A 0.05%, enzyme A 0.1%, enzyme A 0.15%), 6 replicates according to a completely random design (CRD). Another digestibility trial was followed for enzyme complex B. Twenty pigs, average 31.92${\pm}$0.37 kg BW, fitted with simple ileal T-cannulas for digestibility trial. Neither enzyme A nor enzyme B affected on fecal or ileal digestibility of dry matter, gross energy, crude protein, crude fat and crude ash (p>0.05). The apparent fecal digestibilities of all the nutrients were higher in total feces collection method than in indirect method. At the end of feeding trial, 21 pigs were slaughtered for examining the morphological changes of small intestine and the concentration of microorganisms in the ileum and the colon. Growth performance, intestinal morphology and pH of ileum and colon were not affected by the either enzyme complex supplementation (p>0.05). These results suggested that enzyme complex A and enzyme complex B were of no benefit to early-weaned pigs when corn-soybean meal based diet was provided.

Microstructure and friction/wear behavior of (TiB+TiC) particulate-reinforced titanium matrix composites

Choi, B.J.,Kim, I.Y.,Lee, Y.Z.,Kim, Y.J. Elsevier Sequoia [etc.] 2014 Wear: An international journal on the science and Vol.318 No.1

<P>This study examined the microstructure and friction/wear behavior of (TiB+TiC) particulate-reinforced titanium matrix composites (TMCs) fabricated by in situ synthesis. Boron carbide (B4C) particles with 1500 mu m (1500 mu m B4C) or 150 mu m (150 pm B4C) diameter were added to a titanium matrix during vacuum induction melting to provide in situ synthesized (TiB+TiC) particulate reinforcement. The reinforcements prepared with 150 mu m B4C were finer than those prepared with 1500 mu m B4C. The size of the reinforcement particles affected their tendency to fragment under the applied load and thus produce more wear of the TMCs. Therefore, the friction and wear behavior of the TMCs is discussed on the basis of the coefficient of friction, hardness, and reinforcement fragmentation during sliding wear. The fine TMC reinforcements prepared with 150 mu m B4C were more easily fragmented from the Ti matrix than the coarse reinforcements, and this debris further decreased the wear resistance. An adherent transfer layer on the worn surface was formed from hardened particles of oxide debris, reinforcements, and base material. Its presence produced two-body abrasion. (C) 2014 Elsevier B.V. All rights reserved.</P>

Comparison of Motility, Acrosome, Viability and ATP of Boar Sperm with or without Cold Shock Resistance in Liquid Semen at 17℃ and 4℃, and Frozen-thawed Semen

Yi, Y.J.,Li, Z.H.,Kim, E.S.,Song, E.S.,Kim, H.B.,Cong, P.Q.,Lee, J.M.,Park, Chang-Sik Asian Australasian Association of Animal Productio 2008 Animal Bioscience Vol.21 No.2

This study was designed to analyze boar sperm to compare motility, acrosome morphology, viability and ATP by various preservation methods between Duroc boar A with cold shock resistance sperm and Duroc boar B with cold shock sensitivity sperm. Semen volume, sperm concentration, motility and normal acrosome between Duroc boar A and B did not show any differences within 2 h after collection. There were no differences in sperm motility and normal acrosome between boar A and B at 1 day of preservation at $17^{\circ}C$ and $4^{\circ}C$, respectively. However, sperm motility and normal acrosome from 2 day of preservation at $17^{\circ}C$ and $4^{\circ}C$, respectively, were higher for boar A than boar B. The frozen-thawed sperm motility and normal acrosome were higher for boar A than boar B. The sperm viability and ATP concentration according to storage period of liquid semen at $17^{\circ}C$ and $4^{\circ}C$ were higher for boar A than boar B. Also, the sperm viability and ATP concentration of frozen-thawed semen were higher for boar A than boar B. In conclusion, we found out that the original quality of boar semen with cold shock resistance sperm played an important role.

Investigation of PCR-RFLPs within Major Histocompatibility Complex B-G Genes Using Two Restriction Enzymes in Eight Breeds of Chinese Indigenous Chickens

R. F. Xu,K. Li,G. H. Chen,B. Y. Z. Qiang,D. L. Mo,B. Fan,C. C. Li,M. Yu,M. J. Zhu,T. A. Xiong,B. Liu 아세아·태평양축산학회 2005 Animal Bioscience Vol.18 No.7

New polymorphism of major histocompatibility complex B-G genes was investigated by amplification and digestion of a 401bp fragment including intron 1 and exon 2 using polymerase chain reaction-restriction fragment length polymorphism (PCRRFLP) technique with two restriction enzymes of Msp I and Tas I in eight breeds of Chinese indigenous chickens and one exotic breed. In the fragment region of the gene, three novel single nucleotide polymorphisms (SNPs) were detected at the two restriction sites. We found the transition of two nucleotides of A294G and T295C occurred at Tas I restriction site, and consequently led to a nonsynonymous substitution of asparagine into serine at position 54 within the deduced amino acid sequence of immunoglobulin variableregion- like domain encoded by the exon 2 of B-G gene. It was observed at rare frequency that a single mutation of A294G occurring at the site, also caused an identical substitution of amino acid, asparagine 54-to-serine, to that we described previously. And the transversion of G319C at Msp I site led to a non-synonymous substitution, glutamine 62-to-histidine. The new alleles and allele frequencies identified by the PCR-RFLP method with the two enzymes were characterized, of which the allele A and B frequencies at Msp I and Tas I loci were given disequilibrium distribution either in the eight Chinese local breeds or in the exotic breed. By comparison, allele A at Msp I locus tended to be dominant, while, the allele B at Tas I locus tended to be dominant in all of the breeds analyzed. In Tibetan chickens, the preliminary association analysis revealed that no significant difference was observed between the different genotypes identified at the Msp I and Tas I loci and the laying performance traits, respectively.

Ndx(Fe0.9Co0.1)90-xB6Nb₃Cu₁(x=3, 4, 5) 초미세결정립합금의 자기특성

조용수(Y. S. Cho),김만중(M. J. Kim),천정남(Z. N. Qian),김택기(T. K. Kim),박우식(W. S. Park),김윤배(Y. B. Kim) 한국자기학회 1995 韓國磁氣學會誌 Vol.5 No.5

Magnetic properties of Nd_x(Fe_(0.9)Co_(0.1))_(90-x)B_6Nb₃Cu₁(X = 3, 4, 5) melt-spun alloys with 6 at% B content were studied aiming for finding out a new α-Fe based Nd-Fe-B nanocrystalline alloy with good hard magnetic properties. Nd_x(Fe_(0.9)Co_(0.1))_(90-x)B_6Nb₃Cu₁ melt-spun alloys prepared by RSP crystallized to nanocrystalline phase. An optimally annealed Nd₃(Fe_(0.9)Co_(0.1))_(87)B_6Nb₃Cu₁ melt-spun alloys had larger volume ratio of α-Fe (Co) than that of higher Nd content alloy and showed high remanence of about 1.6 T. On the contrary, the increase of Nd content in Nd_x(Fe_(0.9)Co_(0.1))_(90-x)B_6Nb₃Cu₁ alloys gave rise to gradual increase of an amount of Nd₂(Fe, Co)₁₄B phase and improved coercivity. An optimally annealed Nd_5(Fe_(0.9)Co_(0.1))_(85)B_6Nb₃Cu₁ alloy showed the most improved hard magnetic properties. The remanence, coercivity and energy product of the alloy were 1.35 T, 219 ㎄/m (2.75 kOe), and 129 kJ/㎥ (16.2 MGOe), respectively.

A fractional approach to the time-temperature dependence of dynamic viscoelastic behavior

Z. L. Li,Y. Qin,B. Sun,C. L. Jia,W. J. Zhang,B. J. Yan,Q. L. Shi 대한기계학회 2019 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.33 No.1

Fractional derivative and WLF equation are effective in describing the dynamic behavior and time-temperature effect of viscoelastic damping materials, respectively. These approaches have essentially evolved from the viscoelastic constitutive behavior. Based on such intrinsic relation, a fractional time-temperature superposition principle model (FTTSPM) that integrates the fractional constitutive relation and WLF equation was proposed. The parameters of this model were determined by performing tensile and DMA tests, and the master curves at 5 °C constructed by FTTSPM and WLF equation were compared. The theoretical prediction over the extended frequency span as the master curves was made by using the fractional standard linear solid model (FSLSM) to validate FTTSPM. The numerical results show that FTTSPM conforms to the time-temperature superposition principle. The parameters α and B¢ in this model denote the impact of the material and environment on the shifted factor, respectively. For the storage and loss modulus, the extended frequency obtained by FTTSPM is broader than that obtained by the WLF equation. Moreover, the evaluation of the storage and loss modulus by FTTSPM is much closer to the theoretical prediction compared with that by the WLF equation. Therefore, FTTSPM is a concise and experiment-based approach with a higher precision and greater frequency-extended capacity compared with the WLF equation. However, FTTSPM inevitably faces a vertical shift when non-thermo-rheologically simple materials are considered. The physical mechanism and practical application of FTTSPM will be examined in further research.

3㎾급 태양광발전시스템의 경년변화특성

박정국(Z.G. Piao),박정민(J.M. Park),이강연(K.Y. Lee),김평호(P.H. Kim),임양수(Y.S. Lim),조금배(G.B. Cho),오금곤(G.K. Oh) 전력전자학회 2008 전력전자학술대회 논문집 Vol.- No.-

본 논문에서는 태양에너지 실증연구단지에 설치된 서로 다른 2기 3㎾급 태양광발전 시스템에 대한 5년간의 데이터 분석을 통하여 시스템 구성요소인 태양전지와 인버터의 효율 특성 및 시스템의 운전특성의 경년변화에 대하여 비교분석하였다. A 시스템의 경우 PV 어레이 변환효율은 2004년 이후 약 0.2% 정도로 지속적으로 떨어지는 추세를 나타내고 있으며, B시스템의 경우 인버터의 효율은 약 0.5% 정도로 지속적으로 떨어지는 추세를 나타내고 있다. 2기의 PV 시스템의 발전효율, 이용율 및 성능비는 모두 2004년 이후 지속적인 효율저하를 나타내고 있음을 확인 하였다.