995 resultados para 33-316


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A series of complex perovskite solid solutions of Ba[(Mg1-xCdx)(0.33)Nb-0.67]O-3 have been synthesized by the columbite method. Detailed Rietveld refinement of their X-ray diffraction data show that Ba[(Mg1-xCdx)0(.33)Nb(0.67)]O-3 has an order trigonal structure. The ordering degree as determined by the B-site occupancies increases with the partial substitution of Cd for Mg.

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Ti-Zr-V-Mn-Ni-based multi-component alloys demonstrate high discharge capacity in KOH electrolyte. However, the drastic decrease in their discharge capacities makes them unsuitable for use as negative electrode material in the Ni/MH battery. In present work, Ni is partially replaced by Cr in the Ti-Zr-V-Mn-Ni-based alloys to improve their cycle life. The effects of Cr substitution on microstructures and the electrochemical characteristics of the alloys are investigated. It is found that Cr substitution is very effective to improve the cyclic durability of the alloys although the discharge capacity decreases with changing x from 0.05 to 0.20. Some kinetic performances have been also investigated using electrochemical impedance spectroscopy (EIS) and potentiostatic discharge technique.

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Bulk novel cemented carbides (W1-xAlx)C-10.1 vol% Co (x = 0.2, 0.33, 0.4, 0.5) are prepared by mechanical alloying and hot-pressing sintering. Hot-pressing (HP) is used to fabricate the bulk bodies of the hard alloys. The novel cemented carbides have good mechanical properties compared with WC-Co. The density and operating cost of the novel material is much lower than a WC-Co system. The material is easy to process and the processing leads to nano-scaled, rounded, particles in the bulk material. The hardness of (W1-xAlx)C-10.1 vol% Co (x = 0.2, 0.33, 0.4, 0.5) hard material is 20.37, 21.16, 21.59 and 22.16 GPa, and the bending strength is 1257, 1238, 1211 and 1293 MPa, with the aluminum content varying from 20% to 50%. The relationship between the microstructure and the mechanical properties of the novel hard alloy is also discussed.

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采用溶胶-凝胶法制备了不同烧结温度的钙钛矿类锰氧化物La0.67Sr0.33MnO3样品。实验结果表明,在1573 K以上烧结的样品,晶粒出现异常长大,晶界效应明显。随着烧结温度的提高,磁化强度逐渐增大,但样品的居里温度基本不变。此外,在1173和1573 K温度下烧结的样品,均出现了低于居里温度的金属-半导体导电行为转变。在合适的烧结条件下,可以观察到隧道磁电阻(TMR)和超大磁电阻(CMR)2种磁电阻效应。实验表明,自旋电子的输运,不仅与样品平均粒径的大小和密度有关,而且与晶界的微观结构有密切关系。

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W1-xAlxC (x = 0.33, 0.50, 0.75, 0.86) solid solutions have been synthesized directly by ball-milling tungsten powder, aluminum powder and activated carbon. The structural development of W0.5Al0.5C phase with the milling times up to 160 h has been followed using X-ray diffraction. X-ray photoelectron spectra demonstrate that Al atom takes the place of W. High temperature annealing experiment reveals that Al is stable in hexagonal structure to 1873 K. Transmission electron microscopy image shows that the grain size of the prepared powders is about 5 nm.

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This paper presents results concerning structure and electrochemical characteristics of the La0.67Mg0.33 (Ni0.8Co0.1Mn0.1) (x) (x=2.5-5.0) alloy. It can be found from the result of the Rietveld analyses that the structures of the alloys change obviously with increasing x from 2.5 to 5.0. The main phase of the alloys with x=2.5-3.5 is LaMg2Ni9 phase with a PuNi3-type rhombohedral structure, but the main phase of the alloys with x=4.0-5.0 is LaNi(5)phase with a CaCu5-type hexagonal structure. Furthermore, the phase ratio, lattice parameter and cell volume of the LaMg2Ni9 phase and the LaNi5 phase change with increasing x. The electrochemical studies show that the maximum discharge capacity increases from 214.7 mAh/g (x=2.5) to 391.1 mAh/g (x=3.5) and then decreases to 238.5 mAh/g (x=5.0). As the discharge current density is 1,200 mA/g, the high rate dischargeability (HRD) increases from 51.1% (x=2.5) to 83.7% (x=3.5) and then decreases to 71.6% (x=5.0). Moreover, the exchange current density (I-0) of the alloy electrodes first increases and then decrease with increasing x from 2.5 to 5.0, which is consistent with the variation of the HRD. The cell volume reduces with increasing x in the alloys, which is detrimental to hydrogen diffusion and accordingly decreases the low-temperature dischargeability of the alloy electrodes.

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Silicate oxyapatite La-9.33 (SiO6)(4)O-2:A (A = Eu3+, Tb3+ and/or Ce3+) phosphor films and their patterning were fabricated by a sol-gel process combined with soft lithography. X-ray diffraction (XRD), Fourier transform infrared spectroscopy, atomic force microscopy, optical microscopy and photoluminescence spectra, as well as lifetimes, were used to characterize the resulting films. The results of XRD indicated that the films began to crystallize at 800degreesC and the crystallinity increased with the increase in annealing temperatures. Transparent nonpatterned phosphor films were uniform and crack-free, which mainly consisted of rodlike grains with a size between 150 and 210 nm. Patterned thin films with different bandwidths (20, 50 mum) were obtained by the micromoulding in capillaries technique. The doped rare earth ions (Eu3+, Tb3+ and Ce3+) showed their characteristic emission in crystalline La-9.33(SiO6)(4)O-2 phosphor films, i.e. Eu3+ D-5(0)-F-7(J) (J = 0, 1, 2, 3, 4), Tb3+ D-5(3,4)-F-7(J) (J = 3, 4, 5, 6) and Ce3+ 5d (D-2)-4f (F-2(2/5), F-2(2/7)) emissions, respectively. Both the lifetimes and PL intensity of the Eu3+, Tb3+ ions increased with increasing annealing temperature from 800 to 1100 degreesC, and the optimum concentrations for Eu3+, Tb3+ were determined to be 9 and 7 mol% of La3+ in La-9.33(SiO6)(4)O-2 films, respectively. An energy transfer from Ce3+ to Tb3+ was observed in the La-9.33(SiO6)(4)O-2:Ce, Tb phosphor films, and the energy transfer efficiency was estimated as a function of Tb3+ concentration.

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合成了新化合物K_5H[Co_4(VW_9O_(33))·5H_2O,并运用IR,UV-ViS,DTA和单晶X射线衍射对其结构进行了表征.测定结果证实标题化合物具有α-B-Keggin型结构,两个(VW_9O_(33)~(7-)结构单元由四个Co(Ⅱ)O_6 八面体连接.杂多化合物属单斜晶系P2_(1/n),a=1.2307(3)nm,b=2.1250(4)nm,c=1.5817(3)nm,β=91.86(3)°,V=4.1343(14)nm~3,R=0.0895,R_w=0.2180.

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采用固相反应法在Al2O3-B2O3体系中合成了Al4B2O9和Al18B4O33两个相关化合物,测定了在两种基质中Ce3+,Tb3+和Ce3+-Tb3+的光谱,观察到在两种基质中Ce3+的光谱相似,Ce3+的发射峰位置在Al18B4O33中比Al4B2O9稍有红移。实验表明,Al18B4O33将是一种好的发光基质

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Chemically modified electrodes prepared by adsorbing prussian blue on a glassy carbon electrode are shown to catalyse the electro-oxidation of cysteine, N-acetylcysteine and glutathione in acidic media. The catalytic response is evaluated with respect to the potential scan rate, the solution pH, the concentration dependence, and other variables. Covering the electrode with Nafion(R) film improved the stability and reproducibility in liquid chromatography with electrochemical detection to the extent that repetitive sample injections produced relative standard deviations of less than 5% over several hours of operation. The limit of detection was 4 pmol for cysteine, 33 pmol for glutathione and 61 pmol for N-acetylcysteine.

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在室温和液氮温度下研究了(n-C_(16)H_(33)NH_3)_2MX_4(简称C_(16)MX)及其相应化合物n-C_(16)H_(33)NH_3X(简称C_(16)X)于4000~50cm~(-1)范围的红外光谱。结果表明,它们都形成N-H…X型氢键,氢键强度是C_(16)X大于C_(16)MX。后者氢键的强度是按Cl>Br>I的顺序递减。C_(16)MX的光谱性质可按金属离子性质分为Cu~(2+)(Cu~(2+)、Cd~(2+)、Mn~(2+))和Zn~(2+)(Zn~(2+)、Co~(2+))两组,阴离子配位多面体的形状对其光谱性质有明显影响。还比较了室温与低温下的远红外光谱,证明了M—X键是离子键。

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How to refine a near-native structure to make it closer to its native conformation is an unsolved problem in protein-structure and protein-protein complex-structure prediction. In this article, we first test several scoring functions for selecting locally resampled near-native protein-protein docking conformations and then propose a computationally efficient protocol for structure refinement via local resampling and energy minimization. The proposed method employs a statistical energy function based on a Distance-scaled Ideal-gas REference state (DFIRE) as an initial filter and an empirical energy function EMPIRE (EMpirical Protein-InteRaction Energy) for optimization and re-ranking. Significant improvement of final top-1 ranked structures over initial near-native structures is observed in the ZDOCK 2.3 decoy set for Benchmark 1.0 (74% whose global rmsd reduced by 0.5 angstrom or more and only 7% increased by 0.5 angstrom or more). Less significant improvement is observed for Benchmark 2.0 (38% versus 33%). Possible reasons are discussed.

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变态过程是双壳贝类由幼虫向成体转变的一个必不缺少的发育阶段。研究双壳贝类幼虫的变态过程及其机理,对于阐明它们的种群数量变动,促进重要经济双壳贝类增养殖的发展有重要的理论和实践意义。本论文除了用化学物质对几种双壳贝类(海湾扇贝、墨西哥湾扇贝和硬壳蛤)幼虫的变态进行诱导外,主要以激素和神经递质的作用方式为基础,通过直接测定双壳贝类(以海湾扇贝为代表)幼虫体内激素和神经递质、第二信使cAMP等生化物质含量的变化来研究双壳贝类幼虫变态过程中的信息传递途径,从分子生物学和神经生物学角度阐明双壳贝类幼虫变态机理。主要结果如下:1.通过参考国内外大量文献的基础上,较为系统地评述了近二十年来海洋无脊椎动物幼虫附着变态研究的一些进展情况,主要包括诱导因子、附着变态机理模型、人工诱导物的应用和延迟变态四个方面。到目前为止,人们已经发现了许多海洋无脊椎动物幼虫附着变态的诱导物质,主要分为天然诱导物和人工诱导物两大类,一些人工诱导物如GABA、肾上腺素和去甲肾上腺素已经在经济贝类苗种生产中得到应用。幼虫附着变态机理模型主要有长牡蛎(Crassostrea gigas)幼虫附着变态的双调控模型、红鲍(Haliotis rufescens)幼虫附着变态的上行调节模型以及多毛类Phragmatopoma california幼虫附着变态的脂肪酸调控模型。本论文还评述了海洋无脊椎动物幼虫发生延迟变态的原因以及延迟变态对海洋无脊椎动物造成的影响,并提出了解决的方法和今后研究的重点问题。2.在室内用氯化乙酰胆碱、ATP和CaCl_2 3种化学物质对海湾扇贝幼虫的变态进行了诱导实验。结果表明,虽然在个别浓度和处理时间氯化乙酰胆碱和ATP有诱导作用,但总体诱导效果不显著。而10×10~(-3)~40×10~(-3M的CaCl_2在处理12~24h后诱导效果较显著,其诱导效果对处理时间的依赖性较显著,在浓度为40×10~(-3)M和处理时间为24h时诱导效果最好,与对照组相比,变态率提高23.18%。3种诱导物对幼虫死亡率均有显著影响,并且死亡率对浓度和处理时间均有显著的依赖性,浓度越高,处理时间越长,死亡率越高。3.用KCl、肾上腺素、去甲肾上腺素和氯化胆碱进行了墨西哥湾扇贝(Argopectenirradians concentricus Say)幼虫变态的诱导作用实验。结果表明,KCl、肾上腺素、去甲肾上腺素和氯化胆碱对墨西哥湾扇贝幼虫变态均有显著诱导作用。KCl在处理时间为12h~48h范围内均有诱导作用;13.42×10~(-3)M和20.13×10~(-3)M的KCl诱导效果较好,变态率平均提高10%以上。1.O×10~(-6)M~50×10~(-6)M的肾上腺素在处理时间为lh~12h较适宜,此时变态率均提高10%以上。1.0×10~(-6)M~50×10~(-6)M的去甲肾上腺素在处理时间为1h~24h都较适宜,变态率平均均提高10%以上,最高可提高31.07%。0.01×10~(-4)M~1.O×10~(-4)M的氯化胆碱在处理时间为12h~48h时诱导效果均较好,它们之间的平均变态提高率并没有显著差别,均在12%~13%之间。10×10~(-4)M的氯化胆碱在处理时间为12h时诱导效果较明显,变态率可以提高19.14%,超过12h,变态率明显下降,100×10~(-4)M的氯化胆碱明显产生毒害作用,幼虫变态率均为零,而幼虫的死亡率均为100%。4.用KCl、肾上腺素、去甲肾上腺素、L-DOPA、5-羟色胺(5-hydroxytryptamine,Serotonin,5-HT)和GABA(γ-氨基丁酸)进行了不同浓度不同处理时间对硬壳蛤(Mercenaria mercenaria L.)幼虫变态诱导实验。结果表明,KCl、肾上腺素、去甲肾上腺素、L-DOPA和5-羟色胺对硬壳蛤幼虫的变态均有诱导作用,而GABA的诱导 作用不显著。KCl的最佳诱导浓度随处理时间不同而有所不同。当处理时间为1~24h时,KCl的最佳诱导浓度为33.56×10~(-3)M,此时幼虫变态率均提高24%以上,当处理时间为48h时,KCl的最佳诱导浓度为20.13~26.85×10~(-3)M,处理时间为72h时,最佳诱导浓度为13.42×10~(-3)M。肾上腺素和去甲肾上腺素的诱导作用与浓度和处理时间均有关。肾上腺素的最佳处理浓度为100×10~(-6)M,最佳处理时间均为8h,此时幼虫变态率提高最大,为36.97%。当去甲肾上腺素的诱导浓度为100×10~(-6)M,处理时间为8h~16h时,幼虫变态提高率较高,均大于18%,死亡提高率均低于30%,当去甲肾上腺索诱导浓度为500×10~(-6)M时,虽然在8h~16h的处理时间范围内,幼虫变态提高率也较高,均大于18%,但当处理时间超过8h,在16~48h范围内,幼 虫死亡提高率明显升高,均大于50%。L-DOPA的适宜诱导浓度为10×10~(-6)M~50×10~(-6)M,适宜处理时间为8~24h,此时幼虫变态率均提高30%以上,最高可提高79.43%。5-羟色胺的诱导作用较强,其适宜诱导浓度为100×10~(-6)M—1000×10~(-6)M,适宜处理时间为0.5~24h,此时幼虫变态率提高均在30%以上,当处理时间为8h时,最佳诱导浓度为1000×10~(-6)M,此时幼虫变态率提高57.5%,当处理时间为24h时,最佳诱导浓度为100×10~(-6)M,此时幼虫变态率提高69.29%。GABA的诱导作用较弱,最佳诱导浓度随处理时间的不同而有所不同。处理时间为24h和48h时,最佳诱导浓度为0.1×10~(-6)M;处理时间为0.5~16h时,最佳诱导浓度为100×10~(-6)M。5.KCl、肾上腺素、去甲肾上腺索、L-DOPA、5-羟色胺、GABA、茶碱和咖啡因8种诱导物对不同发育阶段海湾扇贝幼虫变态的诱导作用是不同的。13.42×10~(-3)M和20.13×10~(-3)M的KCl对第12天幼虫的变态有抑制作用,变态提高率为负值;之后当幼虫发育至第13和14天时,两浓度的KCl能够明显诱导幼虫变态,变态提高率均高于20%,而对于第16天的幼虫诱导作用有所减弱,变态提高率有所降低;26.85×10~(-3)M的KCl对第12和13天幼虫的变态均有抑制作用,变态提高率为负值,对第14和16天幼虫的变态却有明显的持续的诱导作用,变态提高率分别为22.98%和37.5%。神经递质肾上腺素、去甲肾上腺素、L-DOPA、5-羟色胺和GABA的诱导作用规律基本相似,即对第13天海湾扇贝幼虫的变态有明显的抑制作用,变态提高率均为负值,而对第14天幼虫的诱导作用较显著。茶碱和咖啡因作为影响细胞内cAMP的物质,它们的诱导作用规律与神经递质有所不同。它们对第13天海湾扇贝幼虫变态的诱导效果最好。6.测定了不同发育阶段及人工诱导后海湾扇贝幼虫体内去甲肾上腺素、多巴胺和5-羟色胺含量的变化规律。结果表明,海湾扇贝幼虫体内去甲肾上腺索含量在变态前和变态后没有明显变化,变态前为2352(pg/mg湿重),变态后为2770(pg/mg湿重)。多巴胺和5-羟色胺含量在变态前随幼虫的发育而增加,变态前(第13天)急剧增加,第13天的幼虫比第12天的幼虫分别增加了2.8倍和5.7倍,变态后急剧下降,变态后幼苗比第13天的幼虫分别降低了25.1倍和16.4倍。海湾扇贝幼虫体内DA:NE比和5-HT:NE比在变态前和变态后变化比较剧烈。DA:NE比和5-HT:NE比在变态前(第13天)急剧增加,第13天的幼虫比第12天的幼虫增加了3.O倍(DA:NE比)和5.0倍(5-HT:NE比);变态后急剧降低,变态后幼苗比第13天的幼虫降低了29.8倍(DA:NE比)和19.5倍(5-HT:NE比)。海湾扇贝幼虫经KCl和氯化钙诱导24h后,体内去甲肾上腺素、多巴胺和5-羟色胺以及DA:NE比和5-HT:NE比均有所降低。本实验的结果表明,多巴胺和5-羟色胺可能启动了海湾扇贝幼虫的变态过程。7.茶碱和咖啡因对墨西哥湾扇贝幼虫的变态均有明显诱导作用。它们的诱导作用均对浓度的依赖性较强,对处理时间的依赖性较弱。10×10~(-4)M的茶碱诱导效果最好,平均变态提高率达33%,其次为1.0×10~(-4)M和100×10~(-4)M的茶碱,平均变态提高率分别为23.15%和21.97%。处理时间对茶碱诱导效果影响不显著,在1~24h范围内,平均变态提高率在19.07~26.1%之间变动。10×10~(-4)M的咖啡因诱导效果最佳,4个处理时间的平均变态提高率为36.01%,其次为100×10~(-4)M,平均变态提高率为26.43%。处理时间对茶碱的诱导效果影响不大,在1~24h范围内,平均变态提高率在19.65~22.02%之间变动。8.采用直接测定cAMP的方法来研究cAMP是否参与了海湾扇贝幼虫的变态过程。结果表明,cAMP参与了海湾扇贝幼虫的变态过程。海湾扇贝幼虫体内cAMP含量随着发育阶段的不同而有所变化。在D形幼虫期最低,为73 pmol/(mg蛋白质);当到达壳顶期幼虫时cAMP含量明显增加,比D形幼虫期提高了12.7倍。从壳顶期幼虫到眼点幼虫(100%,第13天)cAMP含量增加速度较慢,各发育阶段分别比前一发育阶段增加了0.4倍、0.3倍和0.2倍。但当幼虫变态后,体内cAMP含量又急剧增加,幼苗体内cAMP含量比眼点幼虫(100%,第13天)增加了6.1倍。当用KCl、肾上腺索和L-DOPA诱导后,幼虫体内cAMP含量明显增加,分别比对照组提高了7.8倍、1.5倍和10.7倍,说明cAMP参与了这3种诱导物诱导海湾扇贝幼虫变态的过程。9.在前面实验结果和参考有关文献的基础上,初步提出了以海湾扇贝为代表的双壳贝类幼虫变态机理模型:幼虫变态分为两个过程:启动过程和后续过程。当幼虫发育到一定阶段,在外界刺激因子的作用下,体内分泌多巴胺和5-羟色胺,多巴胺和5-羟色胺通过某种信号转导途径(如以DG和IP_3为第二信使)启动变态过程,变态过程启动后,又激活以cAMP为第二信使的信号转导途径(暂时称为后续过程),两者共同完成了幼虫的变态过程。

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本文对真鲷心跳期胚胎对5种常用渗透性抗冻剂(DMSO、甘油、甲醇、丙二醇、乙二醇)和3种非渗透性抗冻剂(PVP、PEG-8000、蔗糖)的耐受性进行了研究。渗透性抗冻剂分6个浓度梯度(5%;10%;15%;20%;25%;30%)和3个时间组(10min;30min;1h)。非渗透性抗冻剂中,PVP、PEG-8000分3个浓度梯度(5%、10%、15%)和2个时间组(10min、30min),蔗糖为4个浓度梯度(5%、10%、15%、20%)和2个时间组(10min、30min)。实验结果表明,在渗透性抗冻剂组中,浓度为5%的处理组的孵化率(>90%)与对照组差异均不显著,随着抗冻剂浓度增大及处理时间的延长,真鲷心跳期胚胎的孵化率显著下降(P<0.05),在最高浓度的最长处理时间中胚胎孵化率均降到了0。总体上,真鲷心跳期胚胎对五种渗透性抗冻剂的耐受性从小到大依次为:甲醇 < 甘油 < 乙二醇 < DMSO < 丙二醇。对影响胚胎孵化率的三个因素(抗冻剂、浓度、时间)进行的因素效应分析结果表明,三种因素对孵化率的影响显著(P<0.05),并且浓度效应 > 时间效应 > 抗冻剂效应。在非渗透性抗冻剂组中,蔗糖组胚胎孵化率未呈显著变化;PVP组随着浓度及时间的增大,孵化率显著下降(P<0.05);PEG-8000组随着浓度增大孵化率显著下降(P<0.05),但在两个时间组间差异不显著。相同处理情况下PEG-8000对真鲷心跳期胚胎的毒性要小于PVP。因素效应分析比较结果表明仅时间效应不显著,且抗冻剂效应 > 浓度效应 > 时间效应。 对所用各种抗冻剂进行了渗透压测量,实验中使用的渗透性抗冻剂(5%-30%)的渗透压值在959-7980mOsm/kg之间,均高于使用海水的渗透压值(919mOsm/kg);使用的非渗透性抗冻剂的渗透压值在316-1040mOsm/kg之间,除20%蔗糖渗透压值(1040mOsm/kg)高于海水外,其他非渗透性抗冻剂的渗透压值均要低于海水。对孵化率与相应的溶液渗透压值进行相关回归分析结果表明,渗透性抗冻剂的渗透压与孵化率呈显著的负相关(P<0.05),而非渗透性抗冻剂的渗透压与孵化率相关不显著。渗透性抗冻剂组的回归分析结果表明,二次方程的曲线拟合度最高,得到的回归方程分别为:Y10min = -2×10-8X2 10min - 6×10-5 X 10min + 1.5635 (R2 = 0.713),Y30min= 5×10-8X2 30min-0.0007 X 30min + 2.097(R2 = 0.681),Y1h = 7×10-8X2 1h-0.0008 X 1h+ 2.0397(R2= 0.725)。 在真鲷胚胎对抗冻剂耐受性实验的基础上,挑选五种抗冻剂--10%DMSO、5%甘油、10%甲醇、20%丙二醇、10%乙二醇,浸泡真鲷心跳期胚胎30min后,分别以超速(130℃/min)、快速(20℃/min)、慢速(3℃/min)的速度降温并使用低温显微镜进行观察,依次记录Toif(油球结冰)、Teif(胚胎外部结冰)、Tiif(胚胎内部结冰)等结冰点,Toif值在-9~-23℃之间;Teif值在-21~-35℃之间;Tiif值在-21~-52℃之间。结冰顺序为先油球结冰,然后胚胎外部结冰随之内部马上瞬间变黑形成内部冰晶。随着降温速度的提高,各结冰温度值显著下降。各抗冻剂之间的Teif及Tiif值不同,Toif值之间没有显著差异。对两种玻璃化冷冻方法进行模拟观察,发现胚胎冰晶形成的顺序与非玻璃化过程不同--先内部结冰然后逐渐蔓延至外部形成外部冰晶,而且模拟玻璃化的内部结冰温度Tiif值(-52.56℃)显著(P<0.05)低于使用低浓度的同种抗冻剂超速降温组的Tiif值(-40.11℃)。在快速及慢速降温组中,20%丙二醇组的Tiif要显著的低于其他组(P<0.05);在超速降温中,甲醇组的Tiif值要显著的低于其他组(P<0.05)。在Tiif小于30℃的实验组中获得形态完整胚胎的比例平均仅有30.77%;在Tiif大于30℃的实验组中获得形态完整胚胎的平均比例高达70.37%,模拟玻璃化组达到100%。各抗冻剂之间,复温后胚胎形态完整率10%甲醇组最高(77.78%);其次依次为10%乙二醇(66.67%)、20%丙二醇(55.56%)和10%DMSO(55.56%);5%甘油组最低(11.11%);推测甲醇的对胚胎的渗透效果要好于其他组。综上推测:使用丙二醇、甲醇作为抗冻剂以及玻璃化冷冻保存方法对真鲷心跳期胚胎超低温保存也许较为合适。 我们对低温保存的真鲷精子核DNA损伤进行了研究以期为下一步胚胎遗传物质稳定性研究提供参考依据。研究方法为单细胞凝胶电泳(SCGE),针对研究对象,在实验过程中对传统的碱性单细胞凝胶电泳在铺胶方法、电泳条件等进行了改进。对精子细胞进行预处理,在碱性电泳液中使核DNA双链解链变性后电泳,EB染色lOmin后,在荧光显微镜下观察,每次随机观察50个左右的核DNA。结果表明,对荧光显微镜下观察到的精子核按彗尾长度及荧光强度划分等级,出现损伤的精子核DNA的损伤程度主要为轻度损伤和中度损伤,很少见有完全损伤的真鲷精子核。经5%、10%、18%、20%、25%、30%DMSO冷冻保存后的精子彗星率分别为33.47% ± 8.95%; 35.91% ± 19.44%; 48.95% ± 8.90%; 43.33% ± 11.19%; 55.80% ± 38.94%。鲜精彗星率为31.43 % ± 2.68%。对比真鲷冷冻精液与新鲜精液的精子DNA的损伤状况,表明仅用30% DMSO冷冻精子DNA损伤状况与鲜精差异显著(P<0.05)。 综上所述,渗透性抗冻剂对胚胎的毒性与其渗透压值呈显著的负相关关系。丙二醇对真鲷心跳期胚胎毒性最小,甲醇较其他抗冻剂能更好的渗透入胚胎;玻璃化方法能显著降低Tiif值并能更好的保持超低温保存后胚胎的形态完整性,因此,使用丙二醇、甲醇作为抗冻剂以及玻璃化冷冻保存方法对真鲷心跳期胚胎超低温保存也许较为合适。常规使用的用于超低温保存真鲷精子的DMSO(浓度<15%)不会对精子核物质稳定性造成明显影响。由于胚胎较精子结构要复杂许多,对于真鲷胚胎损伤机理的研究还有大量工作可以开展。

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By applying synthetically multi-subject theories, methods and technology, such as petroleum geology, sedimentology, seep mechanics, geochemistry, geophysics and so on; and by making full use of computer; combining quantity and quality, macroscopic and microscopic, intensive static and active description, comprehensive studying and physical modeling, 3 dimension and 4 dimension description; the paper took Wen-33 block of Zhongyuan oil field as an example; and studied reservoir macroscopic and microscopic parameter changing rule and evolve mechanics in different water-blood stage. The reservoir dynamic model and remaining-oil distribution mode was established, and several results were achieved as follows: (1) Three types of parameter gaining, optimizing and whole data body of Wen33th reservoir were established. Strata framework, structure framework, reservoir types and distribution of Wen33th reservoir were discussed. Reservoir genesis types, space distribution law and evolve rule of Wen33th reservoir were explained. 4D dynamic model of macroscopic parameter of reservoir flow dynamic geologic function of Wen33th reservoir was established. The macroscopic remaining-oil distribution and control factor was revealed. The models of the microscopic matrix field, pore-throat network field, fluid field, clay mineral field of Wen-33 block were established. The characters, changing rules and controlled factors in different water stage were revealed. The evolve rule and mechanics of petroleum fluid field in Wen-33 block reservoir were revealed. Macroscopic and microscopic remaining oil distribution mode of Wen-33 block were established. Seven types, namely 12 shapes of dynamic model of microscopic remaining oil were discussed, and the distribution of mover remaining oil was predicted. Emulation model: mathematical model and prediction model of Wen-33 block were established. The changing mechanics of reservoir parameter and distribution of remaining-oil were predicted. Firstly, the paper putting forward that the dynamic geologic function of petroleum development is the factor of controlling remaining-oil, which is the main factor leading to matrix field, network field, clay mineral field, fluid field, physic and chemical field, stress field and fluid field forming and evolving. (10) A set of theories, methods and technologies of investigating, describing, characterizing and predicting complex fault-block petroleum were developed.