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951.
952.
国产SLC-B(L)催化剂在双峰聚乙烯管材料工业生产中的应用 总被引:1,自引:0,他引:1
将开发的SLC-B(L)催化剂应用于规模为250kt/a的"北星双峰"(Borstar)工艺的聚乙烯(PE)装置,生产的双峰PE管材料的性能指标达到现行企业质量标准的优等品标准。SLC-B(L)催化剂与同类进口催化剂的动力学行为有所不同。SLC-B(L)催化剂的小试聚合评价结果表明,与同类进口催化剂相比,SLC-B(L)催化剂的初始活性较高、氢调敏感性稍差、堆密度较大、小试产品中细粉含量较低。SLC-B(L)催化剂的工业应用结果表明,SLC-B(L)催化剂的活性比进口催化剂高近20%,氢调敏感性较进口催化剂略差,生产的双峰PE管材料粉料的平均粒径略小且细粉含量有所增加。 相似文献
953.
Piotr Wacinski Mariusz Gadzinowski Wojciech Dabrowski Justyna Szumilo Jakub Wacinski Nathalie Oru Eric Vicaut Stanislaw Czuczwar Janusz Kocki Teresa Basinska Stanislaw Slomkowski 《International journal of molecular sciences》2021,22(14)
Atherosclerosis involves an ongoing inflammatory response of the vascular endothelium and vessel wall of the aorta and vein. The pleiotropic effects of statins have been well described in many in vitro and in vivo studies, but these effects are difficult to achieve in clinical practice due to the low bioavailability of statins and their first-pass metabolism in the liver. The aim of this study was to test a vessel wall local drug delivery system (DDS) using PLA microstructures loaded with simvastatin. Wistar rats were fed high cholesterol chow as a model. The rat vessels were chemically injured by repeated injections of perivascular paclitaxel and 5-fluorouracil. The vessels were then cultured and treated by the injection of several concentrations of poly(L,L-lactide) microparticles loaded with the high local HMG-CoA inhibitor simvastatin (0.58 mg/kg) concentration (SVPLA). Histopathological examinations of the harvested vessels and vital organs after 24 h, 7 days and 4 weeks were performed. Microcirculation in mice as an additional test was performed to demonstrate the safety of this approach. A single dose of SVPLA microspheres with an average diameter of 6.4 μm and a drug concentration equal to 8.1% of particles limited the inflammatory reaction of the endothelium and vessel wall and had no influence on microcirculation in vivo or in vitro. A potent pleiotropic (anti-inflammatory) effect of simvastatin after local SVPLA administration was observed. Moreover, significant concentrations of free simvastatin were observed in the vessel wall (compared to the maximum serum level). In addition, it appeared that simvastatin, once locally administered as SVPLA particles, exerted potent pleiotropic effects on chemically injured vessels and presented anti-inflammatory action. Presumably, this effect was due to the high local concentrations of simvastatin. No local or systemic side effects were observed. This approach could be useful for local simvastatin DDSs when high, local drug concentrations are difficult to obtain, or systemic side effects are present. 相似文献
954.
Mohammad Saeed Alejandro Ibez-Costa Alejandra María Patio-Trives Laura Muoz-Barrera Eduardo Collantes Estvez María ngeles Aguirre Chary Lpez-Pedrera 《International journal of molecular sciences》2021,22(14)
Objectives: This study employed genetic and functional analyses using OASIS meta-analysis of multiple existing GWAS and gene-expression datasets to identify novel SLE genes. Methods: Four hundred and ten genes were mapped using SNIPPER to 30 SLE GWAS loci and investigated for expression in three SLE GEO-datasets and the Cordoba -dataset. Blood eQTL for significant SNPs in SLE loci and STRING for functional pathways of differentially expressed genes were used. Confirmatory qPCR on SLE monocytes was performed. The entire 12p11 locus was investigated for genetic association using two additional GWAS. Expression of 150 genes at this locus was assessed. Based on this significance, qPCRs for DNM1L and KRAS were performed. Results: Fifty genes were differentially expressed in at least two SLE GEO-datasets, with all probes directionally aligned. DDX11, an RNA helicase involved in genome stability, was downregulated in both GEO and Cordoba datasets. The most significant SNP, rs3741869 in OASIS locus 12p11.21, containing DDX11, was a cis-eQTL regulating DDX11 expression. DDX11 was found repressed. The entire 12p11 locus showed three association peaks. Gene expression in GEO datasets identified DNM1L and KRAS, besides DDX11. Confirmatory qPCR validated DNM1L as an SLE susceptibility gene. DDX11, DNM1L and KRAS interact with each other and multiple known SLE genes including STAT1/STAT4 and major components of IFN-dependent gene expression, and are responsible for signal transduction of cytokines, hormones, and growth-factors, deregulation of which is involved in SLE-development. Conclusion: A genomic convergence approach with OASIS analysis of multiple GWAS and expression datasets identified DDX11 and DNM1L as novel SLE-genes, the expression of which is altered in monocytes from SLE patients. This study lays the foundation for understanding the pathogenic involvement of DDX11 and DNM1L in SLE by identifying them using a systems-biology approach, while the 12p11 locus harboring these genes was previously missed by four independent GWAS. GSE50395相似文献
955.
Ying KAN Shi-hong ZHANG Li-wen ZHANG Ming CHENG Hong-wu SONG Hong-wei LU 《钢铁研究学报(英文版)》2014,21(9):862-868
The healing behavior of micropores in powder metallurgy (P/M) 316L stainless steel during hot forging and subsequent heat treatment was studied. The results showed that hot forging can improve the homogeneity of the pore size and enhance the relative density of material in varying degree due to different forging temperatures. As a re- sult of deformation and diffusion bonding at high temperature, the irregular pores were spheroidized and finally turned into stable inner grain pores. The comparison of compression behavior between P/M and wrought dense mate rials has shown that the pores can either be the obstacles of dislocation movement or be the nucleation sites accelera- ting the reerystallization according to the difference of deformation temperatures. 相似文献
956.
957.
反渗透浓水回用技术探讨 总被引:3,自引:0,他引:3
本文介绍了反渗透系统浓水用作预处理过滤器的反洗水及部分浓水回收至生水箱用作原水的技术分析及应用。采用此方法后 ,纯水系统的自用水率大大降低 相似文献
958.
In order to obtain an industrial strain with a higher L(+)-lactic acid yield, the strain Rhizopus oryzae RF3608 was mutated by means of nitrogen ion beam implantation and the mutant strain RLC41-6 was isolated. Under optimal conditions the yield of L(+)-lactic acid produced in a shake-flask reached 133 g/L - 137 g/L after 36 h cultivation, indicating that the conversion rate based on glucose was as high as 88% - 91% and the productivity was 3.75 g/L.h. It was almost a 115% increase in lactic acid production compared with the original strain RF3608. 相似文献
959.
960.