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排序方式: 共有6500条查询结果,搜索用时 109 毫秒
61.
Yaoyu Ren Timo Danner Alexandra Moy Martin Finsterbusch Tanner Hamann Jan Dippell Till Fuchs Marius Müller Ricky Hoft André Weber Larry A. Curtiss Peter Zapol Matthew Klenk Anh T. Ngo Pallab Barai Brandon C. Wood Rongpei Shi Liwen F. Wan Tae Wook Heo Martin Engels Jagjit Nanda Felix H. Richter Arnulf Latz Venkat Srinivasan Jürgen Janek Jeff Sakamoto Eric D. Wachsman Dina Fattakhova-Rohlfing 《Liver Transplantation》2023,13(1):2201939
The garnet-type phase Li7La3Zr2O12 (LLZO) attracts significant attention as an oxide solid electrolyte to enable safe and robust solid-state batteries (SSBs) with potentially high energy density. However, while significant progress has been made in demonstrating compatibility with Li metal, integrating LLZO into composite cathodes remains a challenge. The current perspective focuses on the critical issues that need to be addressed to achieve the ultimate goal of an all-solid-state LLZO-based battery that delivers safety, durability, and pack-level performance characteristics that are unobtainable with state-of-the-art Li-ion batteries. This perspective complements existing reviews of solid/solid interfaces with more emphasis on understanding numerous homo- and heteroionic interfaces in a pure oxide-based SSB and the various phenomena that accompany the evolution of the chemical, electrochemical, structural, morphological, and mechanical properties of those interfaces during processing and operation. Finally, the insights gained from a comprehensive literature survey of LLZO–cathode interfaces are used to guide efforts for the development of LLZO-based SSBs. 相似文献
62.
Nitrous oxide emissions from silage maize fields under different mineral nitrogen fertilizer and slurry applications 总被引:6,自引:1,他引:6
J.W. van Groenigen G.J. Kasper G.L. Velthof A. van den Pol-van Dasselaar P.J. Kuikman 《Plant and Soil》2004,263(1):101-111
Intensive dairy farming systems are a large source of emission of the greenhouse gas nitrous oxide (N2O), because of high nitrogen (N) application rates to grasslands and silage maize fields. The objective of this study was to compare measured N2O emissions from two different soils to default N2O emission factors, and to look at alternative emission factors based on (i) the N uptake in the crop and (ii) the N surplus of the system, i.e., N applied minus N uptake by the crop. Twelve N fertilization regimes were implemented on a sandy soil (typic endoaquoll) and a clay soil (typic endoaquept) in the Netherlands, and N2O emissions were measured throughout the growing season. Highest cumulative fluxes of 1.92 and 6.81 kg N2O-N ha–1 for the sandy soil and clay soil were measured at the highest slurry application rate of 250 kg N ha–1. Background emissions from unfertilized soils were 0.14 and 1.52 kg N2O-N ha–1 for the sandy soil and the clay soil, respectively. Emission factors for the sandy soil averaged 0.08, 0.51 and 0.26% of the N applied via fertilizer, slurry, and combinations of both. For the clay soil, these numbers were 1.18, 1.21 and 1.69%, respectively. Surplus N was linearly related to N2O emission for both the sandy soil (R2=0.60) and the clay soil (R2=0.40), indicating a possible alternative emission factor. We concluded that, in our study, N2O emission was not linearly related to N application rates, and varied with type and application rate of fertilizer. Finally, the relatively high emission from the clay soil indicates that background emissions might have to be taken into account in N2O budgets. 相似文献
63.
64.
Petr Vetrovsky Jean-Claude Stoclet Gustav Entlicher 《The international journal of biochemistry & cell biology》1996,28(12):1311-1318
It has been speculated that NG-hydroxy-l-arginine (OH-l-Arg), which is an intermediate in NO production from l-arginine, may be converted to NO by superoxide ion. However, there is still no direct evidence for this conversion. In the present study this was investigated using superoxide ion generated either in acellular or cellular systems. It was found that OH-l-Arg and hydroxylamine were converted to nitrite and nitrate apparently via NO by superoxide ion in aqueous solution. Arginine remained unaffected. These changes were observed during reaction of chemical substances as well as in a biological system (zymosan-activated macrophages in culture). Superoxide dismutase prevented this transformation. OH-l-Arg was also spontaneously hydrolysed to hydroxylamine and l-citrulline, however this occurred at pH > 9 only. Activated microsomes (containing different isoforms of cytochrome P450) were unable to replace NO-synthase in its ability to produce OH-l-Arg from l-arginine. These data support the hypothesis that a pathway alternative to the well-known synthesis of NO by NO-synthase via OH-l-Arg exists. This pathway may involve the production of OH-l-Arg by NO-synthase and decomposition of OH-l-Arg to NO by the action of superoxide ion. Alternatively, hydrolysis of OH-l-Arg to hydroxylamine may occur followed by its oxidation to NO, again by superoxide ion. 相似文献
65.
P. Nicotera M. Ankarcrona E. Bonfoco S. Orrenius S. A. Lipton 《Apoptosis : an international journal on programmed cell death》1996,1(1):5-10
The type of cell death encountered in neuronal cell cultures exposed to excitatory amino acids — such as glutamate, the major excitatory neurotransmitter in the central nervous system, or free radicals, such as nitric oxide (NO.) and superoxide anoin (O2.
–), which react to form peroxynitrite (ONOO–) — appears to depend on the intensity of the exposure and may involve two temporarily distinct phases. Following relatively fulminant insults, an initial phase of necrosis — associated with extreme energy depletion — may simply reflect the failure of neurons to carry out the default apoptotic death program used to efficiently dispose of aged or otherwise unwanted cells. Neurons recovering mitochondrial energy potential after an initial fulminant insult or following a more subtle inciting injury may subsequently undergo apoptosis, possibly associated with a factor released from mitochondria that triggers this death program. The maintenance of balanced energy production may be a decisive factor in detemining the degree, type, and progression of neuronal injury caused by excitotoxins and free radicals. Similar events could possibly occur in vivo after ischemia or other insults. 相似文献
66.
It has been previously reported that iron release from ferritin could be promoted by nitric oxide (NO) generated from sodium nitroprusside. It was thus proposed that some of the toxic effects of NO could be related to its ability to increase intracellular free iron concentrations and generate an oxidative stress. On the contrary, the iron exchange experiments reported here show that NO from S-nitrosothiols is unable to promote iron release from ferritin. The discrepancy may be explained by the disregarded ability of ferrozine, the ferrous trap used in the previous report, to mobilize iron both from ferritin and from sodium nitroprusside spontaneously. 相似文献
67.
David A. Randolph James W. Verbsky Liping Yang Yifu Fang Razqallah Hakem Larry E. Fields 《Transgenic research》1996,5(6):413-420
Gene targeting by double homologous recombination in murine embryonic stem (ES) cells is a powerful tool used to study the cellular consequences of specific genetic mutations. A typical targeting construct consists of a neomycin phosphotransferase (neo) gene flanked by genomic DNA fragments that are homologous to sequences in the target chromosomal locus. Homologous DNA fragments are typically cloned from a murine genomic DNA library. Here we describe an alternative approach whereby the inducible nitric oxide synthase (NOS2) gene locus is partially mapped and homologous DNA sequences obtained using a long-range PCR method. A 7 kb NOS2 amplicon is used to construct a targeting vector where theneo gene is flanked by PCR-derived homologous DNA sequences. The vector also includes a thymidine kinase (tk) negative-selectable marker gene. Following transfection into ES cells, the PCR-based targeting vector undergoes efficient homologous recombination into the NOS2 locus. Thus, PCR-based gene targeting can be a valuable alternative to the conventional cloning approach. It expedites the acquisition of homologous genomic DNA sequences and simplifies the construction of targeting plasmids by making use of defined cloning sites. This approach should result in substantial time and cost savings for appropriate homologous recombination projects. 相似文献
68.
Shigemichi Iha Kunzo Orita Tomoko Kannoh Toshihiko Utsumi Eisuke F. Sato Masayasu Inoue Kozo Utsumi 《Free radical research》1996,25(6):489-498
Effect of nitric oxide (NO) on the respiratory burst of neutrophils was examined under different oxygen tensions. Phorbol myristate acetate (PMA) stimulated oxygen consumption and superoxide (O2-) generation in neutrophils by a mechanism which was inhibited reversibly by NO. The inhibitory effect of NO increased significantly with a decrease in oxygen tension in the medium. The inhibitory effect of NO was suppressed in medium containing oxyhemoglobin (HbO2), a NO scavenging agent. In contrast, 3-morpholinosydnonimine (SIN-1), a compound that rapidly generates peroxynitrite (ONOO-) from the released NO and O2-, slightly stimulated the PMA-induced respiratory burst. These results suggested that NO, but not ONOO, might reversibly inhibit superoxide generation by neutrophils especially at physiologically low oxygen tensions thereby decreasing oxygen toxicity particularly in and around hypoxic tissues. 相似文献
69.
Shoichi Asano Toshio Matsuda Kazuhiro Takuma Hye Sun Kim Tomoaki Sato Takashige Nishikawa Akemichi Baba 《Journal of neurochemistry》1995,64(6):2437-2441
Abstract: The effects of nitric oxide (NO)-generating agents on 45 Ca2+ uptake in rat brain slices and cultured rat astrocytes were studied in the presence of monensin, which is considered to drive the Na+ -Ca2+ exchanger in the reverse mode. Sodium nitroprusside (SNP) at >10 µ M increased monensin-stimulated Ca2+ uptake in the slices, although it did not affect high K+ -stimulated Ca2+ uptake. Another NO donor, 3-morpholinosydnonimine, was effective. The effect of SNP was antagonized by hemoglobin (50 µ M ), a NO scavenger, and mimicked by 8-bromo-cyclic GMP (100 µ M ). In rat brain synaptosomes, SNP increased monensin-stimulated Ca2+ uptake, but it did not affect high K+ -stimulated Ca2+ uptake. 8-Bromocyclic GMP, but not SNP, increased Na+ -dependent Ca2+ uptake significantly in synaptic membrane vesicles in the absence of monensin. In cultured rat astrocytes, SNP and 8-bromo-cyclic GMP increased Ca2+ uptake in the presence of ouabain and monensin, which were required for the Ca2+ uptake in the cells. These findings suggest that NO stimulates the Na+ -Ca2+ exchanger in neuronal preparations and astrocytes in a cyclic GMP-dependent mechanism. 相似文献
70.
Abstract: A component of Hamilton Harbour sediment prevented nitrous oxide (N2 O) reduction in denitrification assays with a mixed population of endogenous bacteria and a pure culture (HH1) isolated from the sediment. A 5% (v/v) concentration of sediment in nutrient broth caused near maximum inhibition of N2 O reduction. Sediment taken from a site closer to pollution sources (Site 906) was twice as inhibitory (as measured by N2 O accumulation) as sediment from Site 910, further from pollution sources. N2 O persistence was associated with the particulate sediment fraction only. Several heavy metals were tested at in situ concentrations, and ionic cadmium (Cd) and chromium (Cr) caused N2 O accumulation. Ashed sediment did not cause N2 O accumulation, but did decrease initial nitrate reduction rates with HH1. 相似文献