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91.
92.
徐亚国 《北京石油化工学院学报》2021,29(1):16-18
为了提高水下设备安装精度与工作效率,基于海上工作经验及查阅国内外相关文献,对水下设备的安装过程进行了研究,其总体过程大致分为5个阶段,即装船固定、提升操作、穿越飞溅区、深水下放、落地坐放;分析了影响水下设备安装过程的主要因素,其中水深主要影响吊放系统和设备在水下的横向偏移;波浪载荷主要应用船舶的动态响应,在设备经历穿越飞溅区阶段时对设备及缆绳造成损伤的风险较大;水下设备自身参数主要影响安装方式和安装船舶的选用。 相似文献
93.
本文参照德国一实例,即利用多种类型PE衬层,在一定温差及有气体扩散阻挡层和无气体扩散阻挡层的条件下,详细地叙述了高压酸性气体对其进行长期渗透作用的试验。结果显示:水蒸气和腐蚀性气体(如H2S)的渗透作用是不能忽视的,甚至当PE层为5mm时亦有一定渗透性;此外,在衬层底部尚产生了化学腐蚀作用,从而促使人们必须考虑须正确选择PE下边的防腐底层。 相似文献
94.
Prof. Ren-Xiao Wang Mi Zhou Hui-Lai Ma Prof. Yuan-Biao Qiao Prof. Qing-Shan Li 《ChemMedChem》2021,16(10):1576-1592
Chronic inflammation represents a long-term reaction of the body's immune system to noxious stimuli. Such a sustained inflammatory response sometimes results in lasting damage to healthy tissues and organs. In fact, chronic inflammation is implicated in the development and progression of various diseases, including cardiovascular diseases, respiratory diseases, metabolic diseases, neurodegenerative diseases, and even cancers. Targeting nonresolving inflammation thus provides new opportunities for treating relevant diseases. In this review, we will go over several chronic inflammation-associated diseases first with emphasis on the role of inflammation in their pathogenesis. Then, we will summarize a number of natural products that exhibit therapeutic effects against those diseases by acting on different markers in the inflammatory response. We envision that natural products will remain a rich resource for the discovery of new drugs treating diseases associated with chronic inflammation. 相似文献
95.
Dr. Daisuke Okuno Dr. Noriho Sakamoto Dr. Mohammed S. O. Tagod Yoshiko Akiyama Dr. Sakiko Moriyama Dr. Takuto Miyamura Dr. Atsuko Hara Dr. Takashi Kido Dr. Hiroshi Ishimoto Prof. Yuji Ishimatsu Prof. Takashi Tanaka Prof. Jun Ishihara Prof. Kohsuke Takeda Prof. Yoshimasa Tanaka Prof. Hiroshi Mukae 《ChemMedChem》2021,16(16):2515-2523
Heat shock protein 47 (HSP47), a collagen-specific molecular chaperone, is causally related to fibrotic diseases, including idiopathic pulmonary fibrosis. The identification of Compounds that interfere with the HSP47-collagen interaction is essential for the development of relevant therapeutics. Herein, we prepared human HSP47 as a soluble fusion protein expressed in E. coli and established an assay system for HSP47 inhibitor screening. We screened a natural and synthetic Compound library established at Nagasaki University. Among 1023 Compounds, 13 exhibited inhibitory activity against human HSP47, of which three inhibited its function in a dose-dependent manner. Epigallocatechin-3-O-gallate, one of these three Compounds, is a typical polyphenol Compound derived from tea leaves. Structurally related Compounds were synthesized and examined for their activity, revealing a hydroxyl group at A-ring position 5 as important for its activity. The present findings provide valuable insight for the development of natural product-derived therapeutics for fibrotic diseases, including idiopathic pulmonary fibrosis. 相似文献
96.
为了提高天然染料对棉纤维的染色固色性能,以聚马来酸(PMA)和柠檬酸(CA)为交联剂应用于天然染料指甲醌对棉织物的交联染色。采用FTIR、SEM和XRD分析了染色前后棉织物的表面形态及结构,探讨了酯交联对棉织物性能的影响以及多元羧酸复配交联染色机理。结果表明,染色前后棉织物表面差别不大,各纤维间不粘连;直接染色后的棉纤维表面变化不明显,仅有少量染料附着,而交联染色后的棉纤维表面负载较多的染料导致其粗糙度增加,酯化反应主要发生在纤维的非晶态区。与直接染色棉织物相比,交联染色棉织物的染色深度(K/S)和上染率分别提高了88%和38%;染品的绿光、黄光增加,颜色饱和度提高;摩擦色牢度提高了1~2级;耐洗色牢度提高了1~2级;交联染色后棉织物的折皱回复角(WRA)提高了约60%,UPF值达到了50+,具有优异的抗紫外性能。 相似文献
97.
98.
Natural polysaccharides (NPS) are regarded as biomolecular and structural components for preparing high-performance tough hydrogels. But the one-step fabrication of NPS-containing hydrogels in seconds and the template-free design of complicated high-resolution structures are still significant challenges in this field. To meet these requirements, various NPS-containing tough hydrogels are fabricated and processed into 2D/3D structures via the combination of Ru(bpy)32+-mediated photochemistry and extrusion 3D printing technique. The whole fabrication process is one-step, completed in tens of seconds under visible light irradiation. It is found that the used NPS plays a key role in achieving the fabrication of high-performance structured tough hydrogels. The high reactivity of functional groups in the used NPS can shorten their gelation times. Long rigid chains of the used NPS, their hierarchical assemblies, and contrasting multinetworks benefit from the efficient dissipation of mechanical energy and enhancement of its operational stability. Strong supramolecular interactions enable hydrogel precursors to have high viscosities, therefore providing good controllability to design high-resolution and complicated tough hydrogel structures via extrusion 3D printing. It is anticipated that this straightforward fabrication strategy and findings will open new horizons for NPS-containing materials. 相似文献
99.
The mechanical properties and post-thermal aging properties of natural rubber (NR) and polybutadiene rubber (BR) blends at
different blending ratios are investigated herein. The experimental results show that both tensile and tear strengths of NR/BR
blends increase with increasing NR content. BR has a higher compression stiffness than NR. The deformation of BR is less than
that of NR under the same load conditions. With regard to aging properties, both tensile stress and strain of NR/BR blends
decrease after prolonged aging. In addition, the stress loss of BR is lower than that of NR, meaning that the aging resistance
property of BR is superior to that of NR. Furthermore, accumulated thermal history has shifted the glass transition temperature
(T
g) of NR/BR blends toward lower temperatures while the loss tangent (tan δ) value increases with prolonged thermal aging. 相似文献
100.