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1.
M油田C2井区阜三段油藏2012年投入开发,初期靠天然能量开采,2013年1月转注水开发,注水井层间矛盾突出形成单层突进,注水效果差。为了提高C2井区阜三段油藏开发效果,本文通过对阜三段油藏沉积特征、储层特征等进行研究,建立三维地质模型,并开展剩余油研究,提出阜三段油藏注采井网调整及稳产方案,方案部署调整井1口、注水井实施分注,方案实施后区块开发效果显著,日产油由初期的39 t/d上升至51.16 t/d。本文为M油田C2井区阜三段油藏稳产增产提供了重要依据,以及对苏北其它油田稳产具有一定的借鉴意义。  相似文献   

2.
C1酯酶抑制剂(C1 esterase inhibitor,C1-INH),又称C1抑制物(C1 inhibitor),是目前已知的唯一一种既能通过经典途径,又能通过凝集素途径对补体系统进行调节的血浆蛋白酶抑制物,其在补体系统、激肽释放酶-激肽系统、纤溶系统和凝血系统中发挥重要的调节作用。目前有4种C1-INH浓缩制剂批准上市,均用于治疗或预防遗传性血管性水肿(hereditary angioedema,HAE)。本文就C1-INH的生化性质与生理功能、相关疾病与临床研究、C1-INH浓缩制剂的制备工艺及产品比较作一综述。  相似文献   

3.
阐述了3C1B高固体分溶剂型涂装工艺(以下简称3C1B高固涂装工艺)的发展历史,从3C1B高固涂装的工艺流程图及参数、3C1B高固涂装工艺优点、3C1B高固涂装工艺VOC控制技术等各方面进行分析和对比,综合生态环境、涂装质量、经济性等各项指标论证了3C1B高固涂装工艺是减少VOC排放、降低能源消耗的精益工艺。  相似文献   

4.
C/C—SiC—Si材料是一种新型的复合材料。本文通过反应熔渗法将液态硅渗入C/C多孔体中得到致密的C/C—SiC—Si复合材料。重点研究了制备C/C多孔体的树脂浸渍裂解法,并测定了在不同浸渍次数下得到的不同的C/C多孔体的体积密度和气孔率,用扫描电镜观察了其形貌,讨论了不同的C/C多孔体对C/C—SiC—Si复合材料最终形貌的影响。  相似文献   

5.
C—C偶联反应作为C—C键构建的一种重要方法,在现代有机合成中应用极其广泛。综述了近年来钯催化剂催化重氮盐的C—C偶联反应的研究进展。该类反应大多具有条件温和、收率高等优点。  相似文献   

6.
过渡金属参与切断苄位C—H键构建C—C键是有机合成化学的研究热点之一。该领域具有广阔的应用前景和发展潜力,可应用于中间体的合成、医药和农药等领域。综述了过渡金属参与切断苄位C—H键构建C—C键的研究进展。  相似文献   

7.
化学气相沉积(CVD)法是目前制备C/C复合材料的首选方法,沉积炉内流场的均匀性直接影响目标产物的质量及产量。本文建立了CVD法制备C/C复合材料的沉积炉内气体流动仿真模型,采用计算流体力学方法对沉积炉内流场进行模拟,并研究主要工艺参数对沉积炉内流场分布的影响规律。结果表明,产品区域气体呈现低速均匀的流动特征,真空度增大会导致沉积炉内气体流速显著增加,但对流场均匀性几乎无影响;采用各路相同的送气方式时沉积炉内流场分布比中心增大的送气方式更均匀;较小进气量可以使沉积炉内流场更均匀。  相似文献   

8.
齐娜  宋伟  刘立明  吴静 《化工学报》2021,72(1):216-228
C—C成键反应是有机合成中构建有机分子碳骨架的关键反应。综述了近年来生物催化Aldol、Acyloin condensation、Stetter 、Pictet-Spengler 等C—C成键反应的关键酶制剂,以及这些酶制剂催化合成β-羟基-α-氨基、α-羟基酮、1,4-二酮、β-咔啉、四氢异喹啉等精细化学品的研究进展。此外,还对生物催化C—C成键反应的应用前景进行了展望,从而扩大生物催化在化学品生产中的应用范围。  相似文献   

9.
ZSM—5沸石阳离子改性用于甲醇转化芳烃的研究,受到国内外学者广泛重视,产物成分复杂,有芳烃、C_+~5脂肪烃、C_1~C_4气态烃和永久性气体,为了提高芳烃收率,除改进催化剂外,急需建立准确而快速的检测方法。本方法采用一台色谱仪装四根分离柱:a.皂土:DNP:PEG_(4000=5:1:1/6201为柱-1(以下简称柱_1);b.60~80目PorapakQS为柱_2(以下简称柱_2);c.80~100目碳分子筛为柱_3(以下简称柱_3);d.40~60目胶酸为柱_4(以下简称柱_4)。靠五个阀的转动,每柱进样1ml,可在1小时45分内完成产物所有组分的全分析。可同时分  相似文献   

10.
C/C镜筒复合材料的性能研究   总被引:2,自引:0,他引:2  
镜筒是高分辨率光学望远镜中的重要零件,其选材和加工质量的好坏及刚度直接决定着最终产品的性能。本试验研究了所研制C/C镜筒复合材料的力学、热学性能,分析了体积密度、炭纤维角度变化以及最终工艺状态对c/c复合材料热膨胀系数的影响。研制的C/C复合材料试验件环向拉伸强度≥160MPa,-40E~60℃线膨胀系数仅为-0.09×10^-6 /K,在满足各项性能指标要求的基础上,成功通过正弦、脉冲振动、动力冲击、真空出气性、光反射等一系列试验考核。  相似文献   

11.
12.
The hepatic metabolism of 1−14C octanoic acid was compared with that of 1−14C palmitic acid in male rats which were fed. After intraportal injection only 1/6 to 1/18 as much octanoic acid as palmitic acid was incorporated into hepatic lipids. In contrast, octanoic acid yielded two to four times as much water-soluble product as did palmitic acid. Similar, but even more impressive, differences between the incorporation of these fatty acids into hepatic lipids were observed in liver slices incubated with14C octanoate and14C palmitate. The oxidation of octanoate to CO2 was more than 10 times as great as that of palmitate. With both substrates, triglycerides comprised almost half the labeled lipid recovered. However octanoate yielded a higher proportion of labeled, unesterified fatty acids and a lower proportion of labeled phospholipid and monoglycerides than did palmitate. Most of the14C recovered in hepatic lipids after incubation with 1−14C octanoate was found in the carboxyl groups of long-chain fatty acids, suggesting that the latter had been synthesized from 2-carbon fragments formed from the oxidation of octanoate. In contrast, only a small fraction of the palmitate was elongated. The similarities and differences between the metabolism of octanoic and palmitic acid in liver and intestine, and the possible nutritional significance of octanoic acid are discussed.  相似文献   

13.
The hepatic metabolism of 1-14C margaric acid, a 17 carbon long chain saturated fatty acid which is present in the liver in trace amounts, was compared with 1-14C octanoic acid and 1-14C palmitic acid to determine if the enhanced oxidation of medium chain fatty acids to CO2 was dependent on fatty acid chain length or the endogenous pool size of the fatty acid substrate. Despite the fact that endogenous margarate is present in trace amounts, there was no significant difference in the oxidation of margarate and palmitate to CO2, while the oxidation of octanoate to CO2 was significantly more rapid. Both margarate and palmitate were more readily incorporated into lipid soluble products in contrast to the low rate of incorporation of octanoate. However, margarate was less readily incorporated into triglyceride, phospholipid and monoglyceride than palmitate. These studies suggest that the chain length rather than hepatic content of the fatty acid determines whether the carboxyl group of equimolar amounts of a 1-14C-carboxyl labeled fatty acid will be preferentially oxidized to CO2 or incorporated into tissue lipid in the liver.  相似文献   

14.
The C1 and C2 stereocenters of α-glucosaminides can be prepared by establishing the stereocenters in either order. For the former, a C2-azido glucosyl donor is prepared first, and the restraining effect of a 4,6-O-benzylidene ring is used to induce α-coupling. For the latter, the C1 linkage is prepared first by use of an n-pentenyl-manno-1,2-orthoester donor which ensures (a) clean α-coupling and (b) a convenient C2-ester. The C2-ester is replaced with a triflate leaving group, and nucleophilic displacement is effected by use of a hypervalent silicon azide.  相似文献   

15.
Etherification of two alkenes, 2-methyl-1-butene and 2,4,4-trimethyl-1-pentene, was studied with seven different C1- to C4-alcohols. Although etherification was of primary interest, the isomerisation of the alkenes was the main reaction to occur. For the primary alcohols the etherification and isomerisation rates correlated well with the properties of the alcohols. Both rates increased with decreasing polarity and with increasing carbon number, acidity and Mulliken charge of the oxygen atom of the alcohol. It is difficult to distinguish the effect of each property separately, and probably the differences in the reactivities are not due to any one property alone but rather the synergy of the properties affects the reactivities. The secondary alcohols behaved in a different way than the primary ones: the etherification was almost negligible. The effect of alcohol on the isomerisation of alkenes was notable even though alcohol does not directly react in the reaction, which was concluded to be due to the stronger adsorption of the more polar alcohols which hinders the reactions of other components.  相似文献   

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17.
This work summarizes the most relevant facets of the current knowledge of the principal catalytic processes involved in one carbon-atom conversions. Without doubt, natural gas (or methane) chemical conversion into high molecular weight hydrocarbons via oxidative coupling (OCM) or partial oxidation into C1 oxygenates (POM) currently represents a great chemical and technological challenge for petrochemistry. Although the catalyst systems and the basic principles of the two types of processes are well known, a greater effort is needed towards the development of more efficient and stable catalysts under the severe operation conditions imposed by the reaction itself, as well as the need for suitable reaction design to minimize the extent of the homogeneous reaction. The alternative process is to obtain synthesis gas (CO/H2) in a first step through steam reforming followed by a second Fischer-Tropsch hydrogenation step. However, the unfavorable energetic balance of the reforming step and the absence of selective catalysts in the latter to obtain a narrow molecular weight distribution currently leads to compromise in solutions. Among these, the high molecular weight alcohol synthesis and the recently developed Shell middle distillate synthesis (SMDS) appear to be very attractive. Of no less importance are the reactions which incorporate a CO molecule into alcohols or olefins via carbonylations and hydroformylations. Within this framework, the use of organometallic complexes anchored to functionalized polymeric matrices initiated a very intense research activity, particularly in the development of stable catalysts.  相似文献   

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Siphonaxanthin is a carotenoid found in certain green algae, and its promising beneficial properties, such as its anti-obesity effect, have recently been demonstrated. However, there is little information about the molecular mechanisms underlying intestinal absorption of siphonaxanthin. In this study, we aimed to elucidate how siphonaxanthin is transported across the intestinal epithelium using differentiated Caco-2 cells (dCaco-2 cells), recombinant proteins, and an animal model. Siphonaxanthin was taken up by dCaco-2 cells, a model of intestinal epithelial cells, and its uptake linearly increased up to at least 6 h. Pharmacological inhibition of Nieman-Pick C1-like 1 (NPC1L1), but not that of scavenger receptor class B type 1 (SR-B1), significantly suppressed siphonaxanthin uptake by dCaco-2 cells. Results from an in vitro binding assay suggested that the N-terminal domain of NPC1L1, which is an extracellular domain of NPC1L1, binds with siphonaxanthin. Moreover, pretreatment with ezetimibe, an inhibitor of NPC1L1, significantly decreased the plasma level of siphonaxanthin following oral administration in mice. Considered together, we concluded that NPC1L1 promotes siphonaxanthin transport across the intestinal epithelium.  相似文献   

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