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A review of the effects of dietary organic acids fed to swine

Journal of Animal Science and Biotechnology 2016年第1期7卷 67-77页

作者： Mocherla v A N Suiryanrayna J v Ramana Livestock Research Station Sri Venkateswara Veterinary University

Animal production depends on nutrient utilization and if done there is an accelerated momentum towards growth with a low cost to feed ratio Public concern over the consumption of pork with antibiotic residues of the animals fed with antibiotic growth promoters （AGP） has paved the way to use other additives like herbs and their products, probiotics, prebiotics etc. Numerous feed additives are in vogue for achieving this target and one such classical example is the usage of organic acids and their salts. Usage of organic acids was in progress for over four decades. Early weaned piglets are （3-4 weeks age） exposed to stress with a reduced feed intake, little or no weight gain. This post weaning lag period is due to a limited digestive and absorptive capacity due to insufficient production of hydrochloric acid, pancreatic enzymes and sudden changes in feed consistency and intake. Lowering dietary pH by weak organic acids was found to overcome these problems. The main activity of organic acids is associated with a reduction in gastric pH converting the inactive pepsinogen to active pepsin for effective protein hydrolysis. Organic acids are both bacteriostatic and bactericidal. Lactic acid has been reported to reduce gastric pH and delay the multiplication of an enterotoxigenic E. coil These acids are the intermediary products in Kreb＇s cycle and thus act as an energy source preventing the tissue breakdown resulting from gluconeogenesis and lipolysis. Excretion of supplemental minerals and nitrogen are minimized with organic acids as these form complexes with minerals and aids for their bio-availability. Short chain fatty cids like acetic, propionic and n-butyric acid produced by microbial fermentation of dietary fibre in the large intestines may increase the proliferation of epithelial cells and have stimulatory effects on both endocrine and exocrine pancreatic secretions in pigs. Organic acids also enhances apparent total tract digestibility and improves growth performa

关键词： Chelation Improved productivity Organic acids Pathogen inhibition Protein utility Swine

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Synthesis of Pharmaceutical Intermediates by Toluene Benzylation over Heteropoly Acids on Different Support

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Journal of Natural Gas Chemistry 2007年第2期16卷 186-192页

作者： v. v. Bokade G. D. Yadav Catalysis Division National Chemical LaboratoryPune 411008India University Institute of Chemical TechnologyMumbai-19India University Institute of Chemical Technology Mumbai-19India

Selective formation of pharmaceutical intermediates like diphenylmethane, dimethyldiphenylmethane, benzyl toluene and benzoic acid by liquid phase, toluene benzylation with benzyl chloride as a benzylating agent, was systematically studied over plane clay （K-10, montmorillonite）, plane H-Beta, plane MFI structured titanosilicate （TS-1） and heteropoly acids [HPA, namely dodecatungstophosphoric acid [H3PO4.12WOa-xH2O] （TPA）, dodeca-molybdo phosphoric acid ammonium salt hydrate [H12Mo12N3040P＋aq] （DMAA）, sodium tungstate hydrated purified [Na12WO4.2H2O] （STH）] supported on clay, H-beta and TS-1. The 20%TPA/Clay, 30%TPA/H-Beta and 30%TPA/TS-1, were observed to be the best catalyst samples over plane clay, plane H-Beta and plane TS-1. The catalyst samples are compared with respect to benzyl chloride conversion and selectivities for diphenylmethane, dimethyl-diphenylmethane, benzyl toluene and benzoic acid. The reaction follows the pseudo-first order rate power law model. The apparent rate constants are calculated and compared with the reported ones.

关键词： toluene benzylation benzyl chloride heteropolyacid diphenylmethane dimethyl-diphenyl methane benzyl toluene benzoic acid

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ZrB_(2)-SiC based composites for thermal protection by reaction sintering of ZrO_(2)+B_(4)C+Si

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Journal of Advanced Ceramics 2017年第4期6卷 320-329页

作者： R.v.KRISHNARAO v.v.BHANUPRASAD G.MADHUSUDHAN REDDY Defence Metallurgical Research Laboratory KanchanbaghHyderabad-500058India

Synthesis and sintering of ZrB_(2)-SiC based composites have been carried out in a single-step pressureless reaction sintering(PLRS)of ZrO_(2),B_(4)C,and Si.Y_(2)O_(3) and Al_(2)O_(3) were used as sintering *** effect of ratios of ZrO_(2)/B_(4)C,ZrO_(2)/Si,and sintering additives(Y_(2)O_(3) and Al_(2)O_(3)),was studied by sintering at different temperatures between 1500 and 1680℃in argon ***_(2),SiC,and YAG phases were identified in the sintered *** as high as 4.2 g/cm^(3),micro hardness of 12.7 GPa,and flexural strength of 117.6 MPa were obtained for PLRS *** material was also prepared by PLRS for tungsten inert gas(TIG)welding of the ZrB_(2)-SiC based *** shear strength of the weld was 63.5 *** PLRS ZrB_(2)-SiC composites exhibited:(i)resistance to oxidation and thermal shock upon exposure to plasma flame at 2700℃for 600 s,(ii)thermal protection for Cf-SiC composites upon exposure to oxy-propane flame at 2300℃for 600 s.

关键词： ZrB_(2) SiC reactive sintering synthesis composites

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Disproportionation of ethylbenzene in the presence of C_8 aromatics

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Journal of Natural Gas Chemistry 2009年第3期18卷 369-374页

作者： N.Sharnappa S.Pai v.v.Bokade Catalysis Division National Chemical Laboratory

The selective synthesis of p-diethylbenzene （p-DEB） by disproportionation of ethylbenzene （EB） in the presence of aromatics like m- and p- xylene isomers has been studied over a pore size regulated HZSM-5 catalyst. The industrial feed having different compositions of ethylbenzene and xylene isomers was used for the experimentation. Hence, they were expected to hinder the movement of reactant molecules both on the external surface and within the zeolite channels. It was observed that irrespective of the different feed compositions the concentration of the xylene isomers was intact in the product. There is no other byproducts formation like para-ethylmethyl benzene. The effects of varying the concentration of aromatic compounds in the feed on ethylbenzene conversion and product distribution over the parent and modified H-ZSM-5 catalyst have been discussed. Ethylbenzene disproportionation reaction follows the pseudo first order reaction with an activation energy of 8.6 kcal/mol.

关键词： ethylbenzene xylene isomers catalyst disproportionation diethylbenzene

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Cladophora mats in a Crimean hypersaline lake:structure,dynamics,and inhabiting animals

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Journal of Oceanology and Limnology 2018年第6期36卷 1930-1940页

作者： Alexandr v.PRAZUKIN Elena v.ANUFRIIEvA Nickolai v.SHADRIN The A.O.Kovalevsky Institute of Marine Biological Research of RAS 2 Nakhimov Av.Sevastopol 299011Russia

Filamentous green algae play an important functional role in element cycling and productivity in the diff erent water bodies. In hypersaline lakes and lagoons of the Crimea, filamentous green algae are present and form bottom and floating mats that occupy large areas with high biomass, up to 4–5 kg(wet biomass)/m2. Cladophora spp. dominated in those mats. Five species of filamentous green algae(Chlorophyta) in Lake Chersonesskoye: C ladophora vadorum(Aresch.) Kütz., C. siwaschensis C. Meyer, C. echinus(Biasol.) Kütz., Ulothrix implexa(Kütz.) Kütz., Rhizoclonium tortuosum(Dillw.) Kütz., and seagrass(Angiospermae) R uppia cirrhosa(Petagna) Grande were found. Cladophora spp. and R. cirrhosa were found in the lake throughout the year, other types of algae were encountered episodically. In most cases the biomass of bottom mat exceeded that of the floating mat. In general, the total biomass of the bottom and floating mats in the lake areas at depths up to 30 cm was in a stable range of values from 100 to 290 mg(dry weight)/cm2. Animal and infusorian average abundance in mats reach high values: infusorians—up to 15 000 000 ind./m2, Cletocamptus retrogressus(Copepoda, Harpacticoida)—up to 730 000 ind./m2, Eucypris mareotica(Ostracoda)—up to 91 000 ind./m2 and Chironomidae larvae(Insecta, Diptera)—up to 140 ind./m2. Those values were much higher than in the plankton.

关键词： green algae mats hypersaline lake photosynthesis invertebrates

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Influence of Zr and Mn additions on microstructure and properties of Mg-2.5wt%Cu-Xwt%Zn(X=2.5,5 and 6.5)alloys

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International Journal of Minerals,Metallurgy and Materials 2022年第9期29卷 1733-1745页

作者： A.v.Koltygin v.E.Bazhenov I.v.Plisetskaya v.A.Bautin A.I.Bazlov N.Y.Tabachkova O.O.voropaeva A.A.Komissarov v.D.Belov Foundry Department National University of Science and Technology(MISiS)Moscow 119049Russia Department of Metallurgy Steel New Production Technologies and Protection of MetalsNational University of Science and Technology(MISiS)Moscow 119049Russia Laboratory of Advanced Green Materials National University of Science and Technology(MISiS)Moscow 119049Russia Department of Materials Science of Semiconductors and Dielectrics National University of Science and Technology(MISiS)Moscow 119049Russia Fianit Laboratory(Laser Materials and Technology Research Center at GPI) Prokhorov General Physics Institute RASMoscow 119991Russia Laboratory of Hybrid Nanostructured Materials National University of Science and Technology(MISiS)Moscow 119049Russia Laboratory of Medical Bioresorption and Bioresistance Moscow State University of Medicine and DentistryMoscow 127473Russia

This work studied the effects of adding Zr and Mn in amounts less than 1wt%on the microstructure,mechanical properties,casting properties,and corrosion resistance of Mg-Zn-Cu alloys containing 2.5wt%Cu and 2.5wt%-6.5wt%*** hardness and electrical conductivity measurements were used to find an optimal heat treatment schedule with the best mechanical *** has been established that Zr significantly increases the yield strength of the alloys due to a strong grain refinement ***,the presence of Mn and Zr has a detrimental effect on alloy’s elongation at *** was shown that the precipitation of the Mg_(2)Cu cathodic phase in the alloy structure negatively affects the corrosion ***,the addition of Mn decreases the corrosion rate of the investigated *** best combination of the mechanical,casting,and corrosion properties were achieved in the alloys containing 2.5wt%Cu and 5wt%***,the Mn or Zr addition can improve the properties of the alloys;for example,the addition of Mn or Zr increases the fluidity of the alloys.

关键词： magnesium alloy Mg-Zn-Cu casting alloy Mn addition Zr addition

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Magnetic nanoparticles and concentrated magnetic nanofluids:Synthesis,properties and some applications

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China Particuology 2007年第1期5卷 43-49页

作者： Ladislau vks Doina Bica Mikhail v. Avdeev Lab Magnetic Fluids CFATR Romanian Academy-Timisoara Division Timisoara Romania National Center for Engineering of Systems with Complex Fluids Univ. Politehnica Timisoara Timisoara Romania Lab Magnetic Fluids CFATR Romanian Academy-Timisoara Division Timisoara Romania Frank Laboratory of Neutron Physics Joint Institute for Nuclear Research Dubna Russia

This paper reviews some recent results concerning chemical synthesis of magnetic nanoparticles and preparation of various types of magnetic nanofluids. Structural properties and behaviour in external magnetic field of magnetic nanofluids will be emphasized with relation to their use in leakage-free rotating seals and in biomedical applications.

关键词： Magnetic nanoparticle Magnetic nanofluid Rotating seal Biomedical application Chemical co-precipitation Structural characterization

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Joining and machining of(ZrB2-SiC)and(Cf-SiC)based composites

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Defence Technology（防务技术） 2018年第5期14卷 385-395页

作者： R.v.Krishnarao G.Madhusudan reddy v.v.Bhanuprasad Defence Metallurgical Research Laboratory KanchanbaghHyderabad500058India

Filler materials of(ZrB_2-SiC-B_4C-YAG) composite were developed for gas tungsten arc welding(GTAW) of the ZrB_2-SiC and Cf-SiC based composites to themselves and to each other. Reaction with filler material,porosity and cracks were not observed at weld interfaces of all the joints. Penetration of filler material in to voids and pores existing in the Cf-SiC composites was observed. Average shear strength of 25.7 MPa was achieved for joints of Cf-SiC composites. By incorporation of Cf-SiC(CvD) ground short fibre reinforcement the(ZrB_2-SiC-B_4C-YAG) composite was machinable with tungsten carbide tool. The joint and machined composites were resistance to oxidation and thermal shock when exposed to the oxy-propane flame at 2300℃ for 300s. The combination of(ZrB_2-SiC-B_4C-YAG) and Cf-SiC based composites can be used for making parts like thermal protection system or nozzles for high temperature applications.

关键词： ZrB2-SiC Composite Sintering Machining Gas tungsten arc welding

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Multiscalar B-L extension based on S_(4)flavor symmetry for neutrino masses and mixing

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Chinese Physics C 2021年第4期45卷 181-191页

作者： v.v.vien H.N.Long Institute of Research and Development Duy Tan University182 Nguyen Van LinhDa Nang CityVietnam Department of Physics Tay Nguyen University567 Le DuanBuon Ma ThuotDakLakVietnam Theoretical Particle Physics and Cosmology Research Group Advanced Institute of Materials ScienceTon Duc Thang UniversityHo Chi Minh CityVietnam Faculty of Applied Sciences Ton Due Thang UnivesityHo Chi Minh CityVietnam

A multiscalar and nonrenormalizable B-L extension of the standard model(SM)with S_(4)symmetry which successfully explains the recently observed neutrino oscillation data is *** tiny neutrino masses and their hierarchies are generated via the type-I seesaw *** model reproduces the recent experiments of neutrino mixing angles and Dirac CP violating phase in which the atmospheric angle(θ_(23))and the reactor angle(θ_(13))get the best-fit values while the solar angle(θ_(12))and Dirac CP violating phase(δ)are in 3σrange of the best-fit value for the normal hierarchy(NH).For the inverted hierarchy(IH),θ13 gets the best-ft value andθ_(23)together withδare in the lσrange,whileθ12 is in 3δrange of the best-fit *** effective neutrino masses are pre-dicted to be(m_(ee))=6.81 mev for the NH and(m_(ee))=48.48 mev for the IH,in good agreement with the most re-cent experimental data.

关键词： neutrino mass and mixing extensions of electroweak Higgs sector flavor symmetries

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Conditions for formation and trapping of the two-ion Coulomb cluster in the dissipative optical superlattice

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Chinese Physics B 2015年第6期24卷 305-313页

作者： I.v.Krasnov Institute of Computational Modeling Siberian DivisionRussian Academy of Sciences

Conditions have been studied under which a polychromatic optical superlattice can form and trap the Coulomb cluster of two strongly interacting ions. In our previous work （Krasnov I v and Kamenshchikov L P 2014 Opt. Comm. 312 192） this new all-optical method of obtaining and confining the Coulomb clusters was demonstrated by numerical simulations for special values of the optical superlattice parameters and in the case of Yb ions. In the present paper the conditions are explicitly formulated, under which the long-lived two-ion cluster in the superlattice cell is formed. The peculiarity of these conditions is the renormalization of the ion-ion Coulomb interaction. Notably, the renormalized Coulomb force is determined by the effective charge which depends on the light field parameters and can strongly differ from the ＂bare＂ ion charge. This result can be accounted for by the combined manifestation of the quantum fluctuations of optical forces, nonlinear dependence of these forces on the velocity, and non-Maxwellian （Tsallis type） velocity distribution of the ions in the optical superlattice. Explicit analytical formulas are also obtained for the parameters of the optical two-ion cluster.

关键词： optical trap ion trap rectified gradient force Coulomb clusters

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