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991.
In this study,the nitrogen removal performance of partial denitrificaiton/anammox(PDA) process was investigated by using an UASB reactor.High total nitrogen(TN) removal efficiency(91.97%) was achieved at an influent nitrogen loading rate of 0.64 kg/(m3·d).Anammox bacteria did execute the function of converting nitrate to nitrite in PDA system according to 15N isotope labeling experiments and the contribution was approximately 36.3%.Candidatus_Brocadia,Candidatus_Kuenenia an...  相似文献   
992.
Placenta accreta spectrum (PAS) accounts for 7% of maternal mortality and is associated with intraoperative and postoperative morbidity caused by massive blood loss, infection, and adjacent organ damage. The aims of this study were to identify the protein biomarkers of PAS and to further explore their pathogenetic roles in PAS. For this purpose, we collected five placentas from pregnant subjects with PAS complications and another five placentas from normal pregnancy (NP) cases. Then, we enriched protein samples by specifically isolating the trophoblast villous, deeply invading into the uterine muscle layer in the PAS patients. Next, fluorescence-based two-dimensional difference gel electrophoresis (2D-DIGE) and MALDI-TOF/MS were used to identify the proteins differentially abundant between PAS and NP placenta tissues. As a result, nineteen spots were determined as differentially abundant proteins, ten and nine of which were more abundant in PAS and NP placenta tissues, respectively. Then, specific validation with western blot assay and immunohisto/cytochemistry (IHC) assay confirmed that heat shock 70 kDa protein 4 (HSPA4) and chorionic somatomammotropin hormone (CSH) were PAS protein biomarkers. Further tube formation assays demonstrated that HSPA4 promoted the in vitro angiogenesis ability of vessel endothelial cells, which is consistent with the in vivo scenario of PAS complications. In this study, we not only identified PAS protein biomarkers but also connected the promoted angiogenesis with placenta invasion, investigating the pathogenetic mechanism of PAS.  相似文献   
993.
通过磁控溅射法在纯钛表面溅射了一层ZrN涂层,研究了Ti/ZrN/瓷界面组织和力学性能.结果表明,Ti/瓷界面由富含Ti,Si,O元素的反应层和钛表面氧化层组成.钛表面溅射ZrN涂层后,Ti/瓷界面的连接转变为Ti/ZrN/瓷界面的连接,ZrN涂层能有效地防止钛表面生成过厚的氧化层.Ti/ZrN/瓷结合强度为29.2MPa,与Ti/瓷结合强度23.5MPa相比,提高了24.3%.  相似文献   
994.
The power conversion efficiency of organic–inorganic hybrid perovskite solar cells has increased rapidly, but the device stability remains a big challenge. Previous studies show the grain boundary (GB) can facilitate ion migration and initiate device degradation. Herein, methimazole (MMI) is employed for the first time to construct a surface “patch” by in situ converting residual PbI2 at GBs. The resultant MMI–PbI2 complex can effectively suppress ion migration and inhibit diffusion of the metal electrodes. The origin of the surface “patch” effect and their working mechanisms are investigated experimentally and theoretically at the microscopic level. It hence demonstrates a simple and effective method to prolong the device stability in the context of GB engineering, which could be extensively applied to perovskite‐based optoelectronics.  相似文献   
995.
Although silicon‐based materials are ideal candidate anodes for high energy density lithium‐ion batteries, the large volumetric expansion seriously damages the integrity of the electrodes and impedes commercial processes. Reasonable electrode design based on adjustable structures of silicon and strong binders prepared by a facile method is still a great challenge. Herein, a three‐pronged collaborative strategy via hollow nanocubes, amorphous Void@SiOx@C, and in situ cross‐linked polyacrylic acid and d ‐sorbitol 3D network binder (c‐PAA‐DS) is adopted to maintain structural/electrode integrality and stability. The all‐integrated c‐PAA‐DS/Void@SiOx@C electrode delivers excellent mechanical property, which is attributed to ductility of the c‐PAA‐DS binder and high adhesion energy between Void@SiOx@C and c‐PAA‐DS calculated by density functional theory. Benefiting from the synergistic effect of accommodation of the hollow structure, protection of outer carbon shell, amorphous Void@SiOx@C, and strong adhesive c‐PAA‐DS binder, c‐PAA‐DS/Void@SiOx@C shows excellent electrochemical performance. Long cycling stability with a reversible capacity of 696 mAh g?1 is obtained, as well as tiny capacity decay after 500 cycles at 0.5 A g?1 and high‐rate performance. The prelithiated Void@SiOx@C||LiNi0.5Co0.2Mn0.3O2 (NCM523) full cell is also assembled and shows a reversible capacity of 157 mAh g?1 at 0.5 C, delivering an excellent capacity retention of 94% after 160 cycles.  相似文献   
996.
997.
998.
To evaluate the ability of Mg–6Zn to replace titanium nails in the reconstruction of the intestinal tract in general surgery, we compared the Mg–6Zn and titanium implants with respect to their effects on rat’s intestinal tract by biochemical, radiological, pathological and immunohistochemical methods. The results indicated that Mg–6Zn implants started to degrade at the third week and disintegrate at the fourth week. No bubbles appeared, which may be associated with intestinal absorption of the Mg–6Zn implants. Pathological analyses (containing liver, kidney and cecum tissues) and biochemical measurements, including serum magnesium, creatinine, blood urea nitrogen, glutamic–pyruvic–transaminase and glutamic–oxaloacetic–transaminase proved that degradation of Mg–6Zn did not harm the important organs, which is an improvement over titanium implants. Immunohistochemical results showed that Mg–6Zn could enhance the expression of transforming growth factor-β1. Mg–6Zn reduced the expression of tumor necrosis factor at different stages. In general, our study demonstrates that the Mg–6Zn alloy had good biocompatibility in vivo and performed better than titanium at promoting healing and reducing inflammation. It may be a promising candidate for stapler pins in intestinal reconstruction.  相似文献   
999.
1000.
以电子转移再生催化剂的原子转移自由基聚合(ARGET ATRP)成功合成了大分子硅烷偶联剂即聚甲基丙烯酸甲酯-b-3-甲基丙烯酰氧基丙基三甲氧基硅烷(PMMA-b-PTMSPMA)。利用所制得的大分子偶联剂对玻璃表面进行了接枝改性,对改性后的玻璃表面形态及疏水性能进行了研究。结果表明,以CuBr2/PMDETA络合物为催化体系,溴化铜(CuBr2)用量为n(CuBr2)/n(单体)=5×10-4时,PMMA段以辛酸亚锡(Sn(EH)2)为还原剂,PTMSPMA段以铜(Cu)为还原剂,用ARGET ATRP两步法成功制备了嵌段共聚物PMMA-b-PTMSPMA。采用"接枝到(graft onto)"方法,在温和的条件下,在玻璃表面接枝上了大分子偶联剂。玻璃表面的接触角可从30°提高到65°,提高了玻璃表面的疏水性。  相似文献   
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