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101.
The human endometrium is a unique tissue undergoing important changes through the menstrual cycle. Under the exposure of different risk factors in a woman’s lifetime, normal endometrial tissue can give rise to multiple pathologic conditions, including endometriosis and endometrial cancer. Etiology and pathophysiologic changes behind such conditions remain largely unclear. This review summarizes the current knowledge of the pathophysiology of endometriosis and its potential role in the development of endometrial cancer from a molecular perspective. A better understanding of the molecular basis of endometriosis and its role in the development of endometrial pathology will improve the approach to clinical management.  相似文献   
102.
Crystalline silicon thin-film solar cells were fabricated on graphite substrates. A laser ablation process was developed for edge isolation of the thin-film cells. The shunt resistance was comparable to otherwise identical cells isolated by plasma etching, while the reproducibility of the laser isolation process was higher. The solar cells were characterized by current-voltage and light beam induced current measurements (LBiC). No interference was detected along the ablated edges. Spatial variations of the minority carrier lifetime are attributed to the grain structure of the seeding layer obtained by the zone melting recrystallization (ZMR).  相似文献   
103.
(S)-Curvularin and its 13-, 14-, and 16-membered lactone homologues were synthesized through a uniform strategy in which a Kochi oxidative decarboxylation and ring-closing metathesis reactions constitute the key processes. In the evaluation of the anti-inflammatory effects of the synthesized compounds in assays using cells stably transfected with a human iNOS promoter-luciferase reporter gene construct, the 14- and 16-membered homologues showed a slightly higher inhibitory effect towards iNOS promoter activity than curvularin itself. However, the larger ring homologues also exhibited higher cytotoxicity, manifest in downregulated eNOS promoter activity. In contrast, the di-O-acetyl and 4-chloro derivatives of (S)-curvularin showed higher inhibitory efficiency towards induction of the iNOS promoter and less negative effect on eNOS promoter activity than curvularin.  相似文献   
104.
The historical development, current status and future prospects of chlor-alkali electrolysis with oxygen depolarized cathodes (ODCs) are summarized. Over the last decades, membrane chlor-alkali technology has been optimized to such an extent that no substantial reduction of the energy demand can be expected from further process modifications. However, replacement of the hydrogen evolving cathodes in the classical membrane cells by ODCs allows for reduction of the cell voltage and correspondingly the energy consumption of up to 30%. This replacement requires the development of appropriate cathode materials and novel electrolysis cell designs. Due to their superior long-term stability, ODCs based on silver catalysts are very promising for oxygen reduction in concentrated NaOH solutions. Finite-gap falling film cells appear to be the technically most mature design among the several ODC electrolysis cells that have been investigated.
Thomas TurekEmail:
  相似文献   
105.
Through-silicon via (TSV) has been used for 3-dimentional integrated circuits. Mechanical stresses in Cu and Si around the TSV were measured using synchrotron X-ray microdiffraction. The hydrostatic stress in Cu TSV went from high tensile of 234 MPa in the as-fabricated state, to ?196 MPa (compressive) during thermal annealing (in situ measurement), to 167 MPa in the post-annealed state. Due to this stress, the keep-away distance in Si was determined to be about 17 μm. Our results suggest that Cu stress may lead to reliability as well as integration issues, while Si stress may lead to device performance concerns.  相似文献   
106.
Magnetic composite particles with a magnetic core consisting of superparamagnetic iron oxide and a cover layer of hydrophobic polyvinylbenzylchloride are described. The magnetite was prepared by precipitation starting with mixed iron II and iron III salts and coating of the solid with oleic acid. The coating is conducted via the liquid–liquid phase transfer. Thereby oleic acid adsorbed on the magnetite surface. In a second step the oleic acid treated magnetite was coated with polyvinylbenzylchloride in a miniemulsion polymerization to get a protective layer. The obtained magnetite core-shell nano-composites with chlorine functionality were characterized by different methods: particle size measurement, acid treatment, iron content, morphology and elemental profiles across the composite particles diameter. The test result reveals the binding of the iron oxide inside the composites which can be also recognize in TEM pictures.  相似文献   
107.
Scanning laser vibrometry was used to investigate the mechanical stability of free‐standing micro‐solid oxide fuel cell (micro‐SOFC) membranes. Arrays of square‐shaped 460 nm thin micro‐SOFC membranes were fabricated on silicon substrates using pulsed laser deposition for the yttria‐stabilized zirconia electrolyte and magnetron sputtering for the platinum electrodes. Resonance frequency, displacement and acceleration measurements were carried out using interferometry analysis of the membrane reflection. The resonance frequencies scale with the reciprocal of the membrane length. At the resonance, the 390 × 390 μm2 micro‐SOFC membranes exhibit an out‐of‐plane displacement of ca. 1.2 μm only. All free‐standing micro‐SOFC membranes survive the resonant vibration without rupturing. These results are promising for the failure‐free implementation of micro‐SOFC in portable electronic devices.  相似文献   
108.
针对光伏供电系统的特点,结合马斯理论可显著缩短充电时间、减少气化、提高充电效率的优点,提出了在光伏供电系统中应用马斯理论进行快速充电的思想,并通过测试对马斯理论的参数K1值进行了深入的实验研究,以探索马斯定律在光伏供电系统中应用的实现方法。结果发现:K1值在任何条件下都并非定值。  相似文献   
109.
The polymer electrolyte distribution in PEMFC electrodes plays an important role for the catalyst utilization and various transport processes in the electrode. Moreover, its influence on the transport processes is not only limited to proton transport but it may also affect gas transport, electron conductivity and water management of the cell. However, experimental techniques to study the polymer electrolyte distribution are scarce. In this paper we present various approaches based on scanning electron microscopy (SEM) and transmission electron microscopy (TEM) to characterize the polymer electrolyte distribution. The methods presented include staining of the polymer electrolyte with heavy metal ions, energy dispersive X-ray (EDX) mapping and energy filtered imaging (EFI). Their use for the analysis of the polymer electrolyte distribution and electrode structure will be presented and current limitations of these techniques will be discussed.  相似文献   
110.
Kunz GJ 《Applied optics》1996,35(18):3255-3260
Single-scatter lidar signals carry information on the spatial atmospheric backscatter coefficient, attenuated by the path-integrated extinction. Assuming that the relationship between the backscatter and the extinction is known, the inverted extinction profile and the path-integrated extinction are uniquely related to the input boundary value. The integrated extinction over a certain range interval is a measure of the optical transmission along that path. In reverse, for a given transmission over the path of interest, the input boundary value is uniquely defined. An analytical expression is derived that describes the input boundary condition for the inversion of the single-scatter lidar equation in terms of the transmission losses over the path of interest. The proposed method is useful in situations in which independent transmission measurements are carried out or in situations in which targets such as multiple cloud layers or beam stops are available in the lidar path. Equations for both the forward and the backward integration method are presented. Compared with the widely accepted inversion schemes that are based on single-point reference extinction values, the proposed method is less sensitive to noise.  相似文献   
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