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1.
Over the past decades, the number of patients with dry eye disease (DED) has increased dramatically. The incidence of DED is higher in Asia than in Europe and North America, suggesting the involvement of cultural or racial factors in DED etiology. Although many definitions of DED have been used, discrepancies exist between the various definitions of dry eye disease (DED) used across the globe. This article presents a clinical consensus on the definition of DED, as formulated in four meetings with global DED experts. The proposed new definition is as follows: “Dry eye is a multifactorial disease characterized by a persistently unstable and/or deficient tear film (TF) causing discomfort and/or visual impairment, accompanied by variable degrees of ocular surface epitheliopathy, inflammation and neurosensory abnormalities.” The key criteria for the diagnosis of DED are unstable TF, inflammation, ocular discomfort and visual impairment. This definition also recommends the assessment of ocular surface epitheliopathy and neurosensory abnormalities in each patient with suspected DED. It is easily applicable in clinical practice and should help practitioners diagnose DED consistently. This consensus definition of DED should also help to guide research and clinical trials that, to date, have been hampered by the lack of an established surrogate endpoint.  相似文献   
2.
ABSTRACT

Fukushima Daiichi nuclear power plants (1F) were damaged by unprecedented severe accident in the great east Japan earthquake, and seawater and freshwater had been injected as an emergency countermeasure for the core cooling. Although, the primary containment vessel (PCV) was not supposed to be exposed to diluted seawater, the PCV will be exposed to diluted seawater environment until fuel debris removal is completed. Therefore, it is necessary to establish a countermeasure of corrosion for the PCVs made of carbon steel. In this study, the effect of the addition of corrosion inhibitor, which is one of the corrosion countermeasures, was investigated by two types of corrosion tests. As a result of the immersion corrosion test, it was found that any of the three kinds of corrosion inhibitor could suppress corrosion of carbon steel. In addition, as a result of the inhibitor interim addition test, it was found that corrosion of carbon steel covered with corrosion products could be suppressed by optimizing the additive amount of corrosion inhibitor in the cooling water.  相似文献   
3.
4.
广州国际会议展览中心标志系统设计   总被引:2,自引:0,他引:2  
以广州国际会议展览中心标志系统的设计为例,对设计手法及理念进行了探讨,希望能对今后类似设施的设计有所启迪。  相似文献   
5.
This study is the first report on synthesis, characterization and catalytic application of propylsulfonic acid-functionalized mesoporous composites based on natural rubber (NR) and hexagonal mesoporous silica (HMS). In comparison with propylsulfonic acid-functionalized HMS (HMS-SO3H), a series of NR/HMS-SO3H composites were prepared via an in situ sol–gel process using tetrahydrofuran as the synthesis media. Tetraethylorthosilicate as the silica source, was simultaneously condensed with 3-mercaptopropyltrimethoxysilane in a solution of NR followed by oxidation with hydrogen peroxide to achieve the mesoporous composites containing propylsulfonic acid groups. Fourier-transform infrared spectroscopy and 29Si MAS nuclear magnetic resonance spectroscopy results verified that the silica surfaces of the NR/HMS-SO3H composites were functionalized with propylsulfonic acid groups and covered with NR molecules. After the incorporation of NR and organo-functional group into HMS, the hexagonal mesostructure remained intact concomitantly with an increased framework wall thickness and unit cell size, as evidenced by the X-ray powder diffraction analysis. Scanning electron microscopy analysis indicated a high interparticle porosity of NR/HMS-SO3H composites. The textural properties of NR/HMS-SO3H were affected by the amount of MPTMS loading to a smaller extent than that of HMS-SO3H. NR/HMS-SO3H exhibited higher hydrophobicity than HMS-SO3H, as revealed by H2O adsorption–desorption measurements. Moreover, the NR/HMS-SO3H catalysts possessed a superior specific activity to HMS-SO3H in the esterification of lauric acid with ethanol, resulting in a higher conversion level.  相似文献   
6.
Conventional microstrip gas chambers (MSGCs) have encountered many difficulties, such as limited gas gain and sparking damages. We propose a new multigrid-type MSGC (M-MSGC) to overcome some of these difficulties. Additional grid strips are inserted between the anode and the cathode in this new type of MSGC. Gaps between these strips are chosen to be as small as 10 μm where one can expect an efficient removal of the surface charge. With the existence of other strips with lower potentials than the anode, the field strength around the neighboring grid to the anode strip is not as high as the conventional small-gap MSGCs. The contribution of the surface streamer to the damage is greatly suppressed because the electric field parallel to the surface is screened by the intermediate grid electrodes. However, additional electrodes also screen all the electric field of the upper part of the substrate, and we cannot observe induced signals from the backside of the substrate. To overcome that difficulty, we propose another signal readout method using a patterning approach. Floating pads are placed close to the cathode strip on the surface of the M-MSGC, and the induced charges are read out via the pads. If the area of the pads is sufficiently large and the positive charges are moving toward the pads, the backside electrodes can sense the induced charge. Collected charges on the pads are leaked through the surface resistance. The backside signal through 2.3-mm-thick glass readout of the position along the cathode strips is successfully confirmed through experimental results  相似文献   
7.

Abstract  

Cr/silicalite-1 and Cr/H[B]MFI catalysts were prepared by the impregnation method, and Cr/H[B]MFI were further treated by steaming. The catalysts were employed for the oxidative dehydrogenation of propane to propylene with CO2 as the oxidant. Cr/H[B]MFI showed significantly higher catalytic activity than Cr/silicalite-1, and steamed Cr/H[B]MFI was superior in the reaction stability to Cr/H[B]MFI. The nature of the supported chromium species have been characterized by a number of physicochemical techniques, such as Raman, UV–vis and NMR. It is concluded that the steaming led to the auto-reduction of some Cr6+ to Cr3+, and resultant Cr3+ species might be located near the boron center in the borosilicate framework to counterbalance the negative charge of the framework. The transformation of Cr6+ species to Cr3+ species, facilitated by the steaming process and the presence of boron in the catalyst, is responsible for the enhanced stability of oxidative dehydrogenation of propane to propylene with carbon dioxide as the oxidant.  相似文献   
8.
Summary The reaction of cellulose with N-carbonyl α-amino acid ester 1 leading to cellulose carbamate 2 was carried out in N,N-dimethylacetamide at 100 °C. For N-carbonyl L-leucine ethyl ester (1a), the degree of the carbamate substituent (DS) in 2a was 2.5 for [1a]/[glucose units in cellulose] = 3.0 and reached ca. 3.0 for [1a]/[glucose units in cellulose] = 4.0. Cellulose carbamate 2a was highly soluble in not only aprotic polar solvents but also other organic solvents such as ethyl ether and methyl alcohol. The chiral discrimination ability of 2a was higher than those of the cellulose carbamates having L-phenylalanine and L-aspartic acid moieties.  相似文献   
9.
Bis(4-dimethylamino-2-dihydroxyphenyl)squaraine (1-1 OHSQ) dyes were deposited on van der Waals surfaces of SnS2 single crystals by two methods, dipping in a dye solution and evaporation of dye solution. Dye morphologies and photosensitization properties on the same samples were studied with atomic force microscopy (AFM) and photoelectrochemical measurements. AFM experiments in air revealed two distinct morphologies of dye aggregates and photocurrent measurements on the same samples in aqueous electrolytes showed correspondingly different photocurrent spectra. Three-dimensional needle-shaped 1-1 OHSQ aggregates aligned along crystal directions and showed a broad excitation spectrum that extended into the near-IR region with a peak around 800 nm. In contrast, flat aggregates presumably consisting of monolayers of 1-1 OHSQ molecules, had a sensitization maximum around 680 nm. Both peaks were red-shifted from absorption peak of 1-1 OHSQ in bulk dichloromethane solution. Spectral differences between these dye aggregates are discussed in terms of intermolecular interactions.  相似文献   
10.
Yamada  T.  Horino  M.  Yokoi  K.  Satoh  M.  Kohno  A. 《Journal of Materials Science Letters》1991,10(14):807-809
Journal of Materials Science Letters -  相似文献   
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