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1.
1. INTRODUCTION Methionine, namely 2-amido-4-thiomethyl butyric acid with a structure of CH3SCH2CH2CHCOOH, is one of the essential amino acids and has two natural enantionmers, D and L-methionine. The mixture of L- and D-isomers can be used as analeptics or nutritive additives to maintain the equilibrium of amino acids of feed [1,2]. L-methionine can release active methyl and accelerate the synthesis of choline, which further speeds up the conversion of the lipid accumulated in liv…  相似文献   
2.
PURE STATE APPROACH TO C(x)_αZ_nLIBINGREN;LINQING(InstituteofMathematics,AcademiaSinica,Beijing100080,China.Projectsupportedbyth?..  相似文献   
3.
§1.IntroductionandResultsLet{Xn,n1}beasequenceofrandomvariableswithacommondistributionfunctionF(x)andletXn1Xn2…Xnnbetheor...  相似文献   
4.
In this paper,we study some permanence and global stability to a nonau- tonomous nonlinear discrete single species system,and obtain some sufficient condition of global stability to the system.  相似文献   
5.
Weperformedthehigh-pressureRaman measurementofthethreenanosizedZnOcrystals. Wefoundthesmallerthesize,thehigherthe pressuretoinducethephasetransitionfrom w櫣rzitetorock-saltstructure. High-pressureRamanmeasurementsof nona-shapedZnOcrystalswerepreformed.The…  相似文献   
6.
Great attention is currently paid to the synthesis of polynuclear transition metal complexes as well as their photochemical, photophysical, and electrochemical properties. The design of multicomponent systems capable of performing useful light- and/or redox-induced function is of special interest1. The oxo-centered carboxylate-bridge trinuclear ruthenium clusters have been investigated extensively during recent decades because they have remarkable electron-transfer properties, intense visibl…  相似文献   
7.
陈颖琪  Lin  Guixu  Wang  Feng  Hu  Jianling  Tan  Zhiming 《高技术通讯(英文版)》2007,13(3):297-301
A multiple MIPS 4Kc processor cores based interrupt processing system is introduced. The interrupt controller plays a key role in the high definition television (HDTV) system-on-a-chip (SoC) platform, especially when it is a multiple processor system. Based on a general introduction to the whole HDTV SoC platform, a layered interrupt controller and its implementation are discussed in detail. The proposed scheme was implemented in our FPGA verification board. The results indicate that our scheme is reliable and efficient. Meanwhile, as a functional intellectual property (IP), the interrupt controller has reusability and expandability with the layered structure.  相似文献   
8.
The solution transformations and properties of the R-matrices for two-component systems under these transformations are analyzed in details.Not all transformed R-matrices can be put into the Skalyanin‘s formalism.For those R-matrices with all required properties,the effects of solution transformations to the six-and eight-vertex systems with open boundary conditions are discussed.these effects can be one of the following types:the Hamiltonian is invariant or transposition-invariant or made in a similarity transformation,or its coupling coefficients are multiplied by an overall factor,or the spin of the system is rotated around the z axis or/and reflected with respect to some plane.In these cases,the transformed systems remain to be integrable.  相似文献   
9.
Sulfonylureaherbicidesisanewclassofherbicidesdiscoveredinthemid-l97O's',whosemodeofactionhasbeenestablishedastheinhibitionofacetolactatesynthase(ALS,alsoreferredasacetohydroxyacidsynthase)'-Muchattentionhasbeenfocussedonthiskindofcompound,sincetheyhaveunprecedenteduserates,ahighdegreeofselectivity,andexcellentenvironmentalsafety'.NumerousmodificationsofthestrUctureofthisclassofherbicideshavebeenreported'.Wehavetakenattentiontothesimi1alltybetweenthesulfonylgroup(-SO2-)andphosphoryIgroup[-P…  相似文献   
10.
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