共查询到20条相似文献,搜索用时 125 毫秒
1.
矿物质催化合成SP及SP—C 总被引:1,自引:0,他引:1
探索出一种以矿物质(橡胶填充剂)为催化剂合成SP及SP-C的新工艺,选择了最佳的工艺条件,此法制成的SP及SP-C产品性能优良,质量稳定。 相似文献
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通过对多种酚醛树脂固化促进剂的一系列考察、试验,成功地开发了酚醛片状模塑料(P-SMC)的碱性固化体系,并研究了P-SMC的潜伏性酸性固化体系;探讨了P-SMC的模压工艺;同时,考察了固化体系与树脂糊中各组分的匹配问题,并对P-SMC与UP-SMC制品性能进行了对比。 相似文献
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通过对多种酚醛树脂固化促进剂的一系列考察、试验,成功地开发了酚醛片状模塑料(P-SMC)的碱性固化体系,并研究了P-SMC的潜伏性酸性固化体系;探讨了P-SMC的模压工艺;同时,考察了固化体系与树脂糊中各组分的匹配问题,并对P-SMC与UP-SMC制品性能进行了对比。 相似文献
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简要介绍了第四次中国石化总公司硫磺回收技术协作组年会上美意德3公司交流的技术,分别为:BOCSURE富氧硫回收工艺、高转化率Claus工艺、Clinsulf-DO工艺和Clinsulf-SDP工艺,反映了目前国外硫回收及尾气处理的部分进展状况。 相似文献
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BR/PVC/SBS三元橡塑热弹性弹性体的配方设计及工艺研究 总被引:1,自引:0,他引:1
介绍了用动态硫化法挤出制备丁腈橡胶/聚氯乙烯/苯乙烯-丁二烯-苯乙烯共聚物(BR/PVC/SBS)三元橡塑热塑性弹性体,并采用DSC、SEM、布拉本达流变仪和力学方法研究其工艺条件、配方组成与结构、性能的关系。本研究的BR/PVC/SBS三元橡胶热塑性弹性体综合了PVC、SBS、BR三者的优点,可用于高档鞋料。 相似文献
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多孔磷酸三钙生物陶瓷的研制 总被引:12,自引:0,他引:12
本研究通过改变多孔磷酸三钙(PTCP)生物陶瓷的组成及制备工艺,制得了性能优良的PTCP生物陶瓷。采用TG-DTA、XRD、SEM、MTS陶瓷实验系统等现代测试技术对PTCP的微观结构、组成及性能进行了分析研究,并探讨了影响PTCP生物陶瓷的生物医学性能及物理性能的因素。 相似文献
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采用高效的RSP-Cu3Si与RSP-Cu3Si/Ag催化剂,气化的PhCl可经过Rochow过程直接合成Ph-SiCl3、Ph2SiCl2及Ph3SiCl。文中讨论了温度、载气流量及时间等因素对催化合成反应的影响。 相似文献
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硅烷(CH3)m(C6H5)nSiCL4—m—n的Rochow合成 总被引:2,自引:0,他引:2
用高效RSP-Su3Si合金催化剂,气化的氯苯PhCl与氯甲烷在400℃同时经过催化剂RSP-Cu3Si可制得重要硅烷化试剂(CH3)mPhnSiCl4-m-no讨论了反应的最佳条件及速度。 相似文献
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用高效RSP-Cu_3Si合金催化剂,气化的氯苯PhCl与氯甲烷在400℃同时经过催化剂RSP-Cu_Si可制得重要硅烷化试剂(CH_3)_mPh_nSiCl_(4-m-n)讨论了反应的最佳条件及速度。 相似文献
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Since the widespread use of exogenous lung surfactant to treat neonatal respiratory distress syndrome, premature infant survival and respiratory morbidity have dramatically improved. Despite the effectiveness of the animal-derived surfactant preparations, there still remain some concerns and difficulties associated with their use. This has prompted investigation into the creation of synthetic surfactant preparations. However, to date, no clinically used synthetic formulation is as effective as the natural material. This is largely because the previous synthetic formulations lacked analogues of the hydrophobic proteins of the lung surfactant system, SP-B and SP-C, which are critical functional constituents. As a result, recent investigation has turned toward the development of a new generation of synthetic, biomimetic surfactants that contain synthetic phospholipids along with a mimic of the hydrophobic protein portion of lung surfactant. In this Account, we detail our efforts in creating accurate mimics of SP-C for use in a synthetic surfactant replacement therapy. Despite SP-C's seemingly simple structure, the predominantly helical protein is extraordinarily challenging to work with given its extreme hydrophobicity and structural instability, which greatly complicates the creation of an effective SP-C analogue. Drawing inspiration from Nature, two promising biomimetic approaches have led to the creation of rationally designed biopolymers that recapitulate many of SP-C's molecular features. The first approach utilizes detailed SP-C structure-activity relationships and amino acid folding propensities to create a peptide-based analogue, SP-C33. In SP-C33, the problematic and metastable polyvaline helix is replaced with a structurally stable polyleucine helix and includes a well-placed positive charge to prevent aggregation. SP-C33 is structurally stable and eliminates the association propensity of the native protein. The second approach follows the same design considerations but makes use of a non-natural, poly-N-substituted glycine or "peptoid" scaffold to circumvent the difficulties associated with SP-C. By incorporating unique biomimetic side chains in a non-natural backbone, the peptoid mimic captures both SP-C's hydrophobic patterning and its helical secondary structure. Despite the differences in structure, both SP-C33 and the SP-C peptoid mimic capture many requisite features of SP-C. In a surfactant environment, these analogues also replicate many of the key surface activities necessary for a functional biomimetic surfactant therapy while overcoming the difficulties associated with the natural protein. With improved stability, greater production potential, and elimination of possible pathogenic contamination, these biomimetic surfactant formulations offer not only the potential to improve the treatment of respiratory distress syndrome but also the opportunity to treat other respiratory-related disorders. 相似文献
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Surfactant protein C (SP-C) exists in α-helical and β-sheet conformation. The influence of these conformations on the surface behavior of spread layers containing dipalmytoyl phosphatodylcholine and the surfactant protein B was investigated. The β-sheet conformation of SP-C, which is formed during the preparation procedure at high lipid/protein concentrations, was confirmed by using circular dichroism (CD) and FTIR spectroscopy. Using a captive bubble device, the surface pressure/area isotherms, the surface dilatational elasticity and viscosity, and the main relaxation times of a transient stress relaxation were determined. Surface layers containing SP-C in β-sheet have no protein squeeze-out plateau. The surface dilatational elasticity is increased, which leads to a film of low compressibility. The relaxation times were increased by more than one order of magnitude, and the decays after surface compression and dilatation did not approach each other. Therefore, the surface behavior of layers containing SP-C in β-sheets remarkably differs from those containing SP-C in α-helical conformation. The presence of β–SP-C prevents the film from meeting the function of a pulmonary surfactant layer. 相似文献
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宝鸡氮肥厂尿素装置改造中引进SP专利技术,且大部分设备实现了国产化。简述该改造装置的工艺特点和试车情况;并对出现的问题提出解决办法 相似文献
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<正>天然橡胶(NR)和丁苯橡胶(SBR)常用作轮胎胎面胶的主体材料,而轮胎胎侧胶是贴覆于外胎侧壁表面的覆盖胶层,起着保护帘布层免受潮湿、大气作用及机械损伤等,一般要求胎侧胶料具有耐曲挠疲劳、耐臭氧老化等性能。 相似文献
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抗生素在地表水中广泛检出,且可诱导细菌菌群抗药性,因而发展新型抗生素的去除技术势在必行。本研究基于二茂铁(Fc)良好的可逆化学特性、难溶于水、环境友好特性发展了一种光助-二茂铁/H_2O_2(Fc+H_2O_2+UV)氧化技术。以水环境中经常检出的磺胺吡啶为模型化合物,研究了磺胺吡啶在该氧化体系中的降解行为。研究结果发现,相对于常见的Fenton体系,磺胺吡啶在Fc+H_2O_2+UV体系中呈现出优异的降解效率。自由基淬灭实验发现·OH是主导磺胺吡啶降解的最主要活性物种。自由基探针实验证实Fc+H_2O_2+UV体系中存在电子转移过程,H_2O_2接受电子后产生·OH进而促进磺胺吡啶降解。 相似文献
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Blanca J. Valdovino-Navarro Salvador Dueas G. Isaí Flores-Acosta Jahaziel Gasperin-Bulbarela Johanna Bernaldez-Sarabia Olivia Cabanillas-Bernal Karla E. Cervantes-Luevano Alexei F. Licea-Navarro 《International journal of molecular sciences》2022,23(20)
Severe Acute Respiratory Syndrome Coronavirus 2 is the causal pathogen of coronavirus disease 2019 (COVID-19). The emergence of new variants with different mutational patterns has limited the therapeutic options available and complicated the development of effective neutralizing antibodies targeting the spike (S) protein. Variable New Antigen Receptors (VNARs) constitute a neutralizing antibody technology that has been introduced into the list of possible therapeutic options against SARS-CoV-2. The unique qualities of VNARs, such as high affinities for target molecules, capacity for paratope reformatting, and relatively high stability, make them attractive molecules to counteract the emerging SARS-CoV-2 variants. In this study, we characterized a VNAR antibody (SP240) that was isolated from a synthetic phage library of VNAR domains. In the phage display, a plasma with high antibody titers against SARS-CoV-2 was used to selectively displace the VNAR antibodies bound to the antigen SARS-CoV-2 receptor binding domain (RBD). In silico data suggested that the SP240 binding epitopes are located within the ACE2 binding interface. The neutralizing ability of SP240 was tested against live Delta and Omicron SARS-CoV-2 variants and was found to clear the infection of both variants in the lung cell line A549-ACE2-TMPRSS2. This study highlights the potential of VNARs to act as neutralizing antibodies against emerging SARS-CoV-2 variants. 相似文献
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Shao-Ju Shih Yu-Jen Chou Leon Valentino Posma Panjaitan 《Ceramics International》2013,39(8):8773-8779
Mesoporous bioactive glasses (MBGs) have recently been applied as important bone implant materials due to their high reactive surface areas and superior bioactivities. Various processes have been developed to fabricate MBGs. Among them, the sol–gel process is one of most popular. However, sol–gel has the drawbacks of discontinuous processing and long processing time, making it unsuitable for mass production. This study demonstrates a successful synthesis of MBGs using a spray pyrolysis (SP) method to overcome these problems. The bioactivities of the SP synthesized MBGs are correlated with the main SP processing parameter of calcination temperatures and their structures. Comparisons of the surface areas and bioactivities for the MBG particles prepared from the sol–gel and the SP process are included. Finally, the MBG formation mechanism using SP is proposed. 相似文献
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Fangfang Zhang Rong Ji Nannan Sun Jian Xu Xu Zhang Xiaoli Song Junliang Liu Ming Zhang Shiping Zhang Longlong Niu 《应用聚合物科学杂志》2020,137(42):49272
Spiropyran (SP) derivatives with different hydroxyl groups have been synthesized and incorporated with polyurethane (PU) to prepare mechano-chromic composites. With the content of hydroxyl groups in SP increasing, the stress transfer along PU molecular chain to SP have been effectively enhanced, resulting in the refined mechano-chromic response. The correlation coefficient between mechano-chromic efficiency and effective stress has been defined, which increased by using bishydroxyspiropyran (SP2) instead of SP. With an optimized SP2 content of 1.5 wt%, the composites demonstrated the improved mechano-chromic effect and mechanical properties. The double hydroxyl groups in SP2 grasped the PU chain in form of chemical bonding, leading to construction of micro-phase structures in PU matrix. 相似文献
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随着水泥熟料煅烧技术的发展,新型干法水泥生产线已使单位水泥熟料的热耗大幅度下降,但窑头熟料冷却机(AQC)和窑尾预热器(SP)等排放的低温废气热量约占水泥熟料烧成总耗热量的30%以上,因此回收其中的低温余热从而进一步降低水泥生产热耗是十分必要的。某水泥公司现有3条1000t/d回转窑生产线,满负荷生产条件下,窑头可产生平均温度为380℃,流量为1.395×105 Nm3/h的烟气,窑尾可产生平均温度为330℃,流量为2.76×105Nm3/h的烟气,根据此公司余热热源情况,经计算,装机方案确定为:1台额定容量为5 MW的单压凝汽式汽轮发电机组、3台单压AQC余热锅炉和3台单压SP余热锅炉。 相似文献