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81.
Summary Summary
The assigned chirality at each center of the synthetic nonapeptide histrelin (L-pyroglutamyl-L-histidyl-L-tryptophyl-L-seryl-L-tyrosyl-D-Nim-benzyl-histidyl-L-leucyl-L-arginyl-L-proline-ethylamide) was verified using chiral gas chromatography. The procedure involved
acid hydrolysis of histrelin to the constituent amino acids, derivatization as the N-pentafluoropropionyl/isopropyl esters
and the analysis of the mixture using a commercially available 25m chiral capillary column (Chirasil-L-Val). There was no
significant difference in the retention time of the amino acids obtained from the hydrolysate mixture when compared to the
appropriate standards. Additionally, the hydrolysate was spiked with the D and L amino acids to prove the identity of closely
eluting peaks.
Luteinizing hormone-releasing hormone 相似文献
82.
《Macromolecular rapid communications》2017,38(16)
Herein, the development and characterization of a 3D gradient structure of gold nanoparticles is described. The gradient of gold nanoparticles is made in situ in a macroporous nonionic block copolymer hydrogel matrix, through gold ion diffusion control. The polymer provides a matrix for diffusion of gold ions, acts as a template for controlling nanoparticle growth, and facilitates the in situ reduction of gold ions to gold nanoparticles. A clear gradient in gold nanoparticles is observed across the 3D space of the polymer matrix using scanning electron microscopy, fluorescence microscopy, atomic force microscopy, and thermogravimetric analysis. The particle gradient is further functionalized with both hydrophobic and hydrophilic groups via thiol‐gold linkage to demonstrate the ability to form gradients with different chemical functionalities. Using additive manufacturing, the polymer can also be printed as a porous network with possible applications for 3D cell culturing in, e.g., biomaterials research. 相似文献
83.
Huaping Xu Dr. Jurriaan Huskens Prof. Dr. 《Chemistry (Weinheim an der Bergstrasse, Germany)》2010,16(8):2342-2348
Microcontact printing is a heavily used surface modification method in materials and life science applications. This concept article focuses on the development of versatile stamps for microcontact printing that can be used to bind and release inks through molecular recognition or through an ink reservoir, the latter being used for the transfer of heavy inks, such as biomolecules and particles. Conceptually, such stamp properties can be introduced at the stamp surface or by changing the bulk stamp material; both lines of research will be reviewed here. Examples include supramolecular stamps with affinity properties, polymer‐layer‐grafted PDMS stamps, and porous multilayer‐grafted PDMS stamps for the first case, and hydrogel stamps and porous stamps made by phase‐separation micromolding for the second. Potential directions for future advancement of this field are also discussed. 相似文献
84.
85.
Jong Seob Choi 《European Polymer Journal》2010,46(3):389-15196
Highly conductive and transparent poly(3,4-ethylenedioxythiophene) (PEDOT) thin films can be prepared effectively via vapor-phase polymerization (VPP) with the addition of imidazole (Im) based derivatives. The addition of Im that has one and/or two alkyl substituents significantly improved the electrical conductivity of PEDOT thin films. In an effort to develop a facile PEDOT micro-patterning method, we investigated ink-jet printing and soft lithography. The procedure of oxidant patterning with a weak base followed by VPP of a 3,4-ethylenedioxythiophene (EDOT) monomer provides an effective and simple method for micro-patterning of an intrinsic conductive polymer (ICP). 相似文献
86.
以丝阵内爆零维模型为基础,采用Pspice模拟行为建模方法,建立了丝阵内爆动态电感与Z箍缩驱动器耦合的全电路模型,实现驱动器放电过程与丝阵内爆过程的自洽求解,并研究了丝阵参数、电路参数对内爆过程的影响.结果表明:丝阵负载与驱动器存在强耦合关系,丝阵参数、电路参数对丝阵峰值箍缩电流、内爆时间、内爆动能影响很大;在驱动器参数不变,内爆时间不超过电路固有放电周期1/4的前提下,峰值箍缩电流、内爆时间、内爆动能随丝阵质量的增加而增大,内爆时间随丝阵初始半径的增加而增大;在丝阵参数不变时,随着驱动器等效电容的增大,内爆时间减小,丝阵内爆动能增大,但驱动器储能转化为内爆动能的效率却先增大后减小.对于特定的驱动器,优化的丝阵参数应使内爆过程充分利用驱动器固有放电周期的上升沿,使丝阵快速收缩的时间起点接近电路固有放电周期的四分之一,以获得最大的动能效率.
关键词:
Z箍缩驱动器
零维内爆模型
模拟行为建模
耦合特性 相似文献
87.
通过从一个导数值等式的证明谈起,探讨教师在课堂教学中如何根据教学内容创设能激起学生新异感的问题情景,启发和引导学生发散思考,类比、联想、猜想,探索和发现新问题并给出解答.使学生思维不断攀升,丰富教学内容,激发学生兴趣,培养学生科学思维方法和创新能力. 相似文献
88.
Marie Devert 《Tetrahedron》2010,66(35):7227-2584
The first total synthesis of (±)-17-norcamptothecin, a novel camptothecin analog possessing an α-hydroxy-γ-lactone E-ring, has been accomplished by using a short and flexible route. The stability of this new compound in aqueous medium has been evaluated through fluorescence spectroscopy. 相似文献
89.
Michael W. Lodewyk 《Tetrahedron letters》2010,51(1):170-173
Syntheses of several (sulfonyl)methylphosphonate analogs of geranyl, neryl, and farnesyl diphosphates are described. Key steps include utilization of an (E)-selective Horner-Wadsworth-Emmons olefination which couples an aldehyde to the sulfone phosphonate moiety, and a selective reduction of the resulting dienyl sulfone phosphonate substrates. 相似文献
90.
A network for motion detection of an approaching object without influence of the moving background was proposed based on the
insect visual system. The two-dimensional array of the analog complementary metal oxide semiconductor (CMOS) circuits for
extracting the edge signals of the approaching object without outputting those of the moving background was inserted at the
first stage of the network. At the next stage, analog CMOS circuits for detection of approaching velocity and direction, which
accept the extracted edge signals, were inserted based on the locust vision system. A chip of the proposed network was fabricated
with the 1.2 mm CMOS process. It was clarified from the measured results and the simulation results with the simulation program
with integrated circuit emphasis (SPICE) that the two-dimensional circuits of the first stage can only generate the signals
of target edges. The measured results showed that the chip can detect the approaching velocity and direction of the target
in the image which contains the moving background. 相似文献