Recent advances in hydrogen storage technologies based on nanoporous carbon materials

AbstractHydrogen is a promising energy carrier that can potentially facilitate a transition from fossil fuels to sustainable energy sources without producing harmful by-products. Prior to realizing a hydrogen economy, however, viable hydrogen storage materials must be developed. Physical adsorption in porous solids provides an opportunity for hydrogen storage under low-stringency conditions. Physically adsorbed hydrogen molecules are weakly bound to a surface and, hence, are easily released. Among the various surface candidates, porous carbons appear to provide efficient hydrogen storage, with the advantages that porous carbon is relatively low-cost to produce and is easily prepared. In this review, we summarize the preparation methods, pore characteristics, and hydrogen storage capacities of representative nanoporous carbons, including activated carbons, zeolite-templated carbon, and carbide-derived carbon. We focus particularly on a series of nanoporous carbons developed recently: metal–organic framework-derived carbons, which exhibit promising properties for use in hydrogen storage applications

KINEMATIC FACTORS AFFECTING THE SCORE IN ARCHERY: USING SEM

INTRODUCTION: The shooting movements of Archery are paths of continuous and causal movements. Structural equation modeling (SEM) grows out of and serves purposes similar to multiple regression and may be used as a more powerful alternative to multiple regression, path analysis, factor analysis, time series analysis, and analysis of covariance. Some reachers in marketing have used SEM to analyze data deprived from experiments (e.g.,Mackenzie,Lutz, and Belch,1986; Ryan,1982). The purpose of this study was to investigate the structural equations between kinematic factors affecting score during backtension which was basic and important in archer

Unusual thermopower of inhomogeneous graphene grown by chemical vapor deposition

We report on thermopower (TEP) and resistance measurements of inhomogeneous graphene grown by chemical vapor deposition (CVD). Unlike the conventional resistance of pristine graphene, the gate-dependent TEP shows a large electron-hole asymmetry. This can be accounted for by inhomogeneity of the CVD-graphene where individual graphene regions contribute with different TEPs. At the high magnetic field and low temperature, the TEP has large fluctuations near the Dirac point associated with the disorder in the CVD-graphene. TEP measurements reveal additional characteristics of CVD-graphene, which are difficult to obtain from the measurement of resistance alone

Quantum Hall effect in graphene decorated with disordered multilayer patches

Quantum Hall effect (QHE) is observed in graphene grown by chemical vapour deposition using platinum catalyst. The QHE is even seen in samples which are irregularly decorated with disordered multilayer graphene patches and have very low mobility (<500 cm2V−1s−1). The effect does not seem to depend on electronic mobility and uniformity of the resulting material, which indicates the robustness of QHE in graphene

A Toxicological Study of HangAmDan-B in Mice

AbstractThe aim of the study was to define the toxicity of HangAmDan-B (HAD-B) in mice over the short and long term. HAD-B was studied in 1-week single and 5-week repeated oral dose toxicity tests on male Imprinting Control Region mice. Doses used in 1 week single oral dose toxicity tests were 0, 0.2, 1, 5, and 25 g/kg/day and those of repeated toxicity test were 0, 0.04, 0.2, 1, and 2 g/kg/day. Blood and urine samples were assayed and their morphology observed. Numerical data were compared using Mann-Whitney U test and analysis of variance. Significantly decreased red blood cell levels in mice from S2-HAD-B, S3-HAD-B, S4-HAD-B, and S5-HAD-B groups were observed in single oral dose toxicity tests. Hemoglobin, hematocrit, and mean cell hemoglobin values in mice from the S4-HAD-B and S5-HAD-B groups were also significantly decreased. No mortalities or significant differences in all factors were observed during the dosing period of the repeated dose toxicity test. Administering 2 g/kg/day of HAD-B in mice over a 5-week period showed no significant hematological changes. However, risk of anemia with more than 5 g/kg/ day administration of HAD-B was found. In general, HAD-B appears to be safe and nontoxic, and a no observed adverse effect level in mice was established at 2 g/kg/ day. This data serves as satisfactory preclinical evidence for the safety of HAD-B should a future clinical trial for HAD-B be launched. Further studies are required to confirm these safety results and to carry out a safety trial in humans

Successful Endourologic Management of Lower Pole Moiety Ureteropelvic Junction Obstruction in a Partially Duplicated Collecting System

We present two cases of symptomatic lower pole moiety ureteropelvic junction obstruction (UPJO) in a partially duplicated collecting system that were successfully treated with minimally invasive endourologic procedures. In the first case, we performed retrograde endopyelotomy with the Acucise® ureteral cutting balloon device, and in the latter case, we performed percutaneous nephrolithotomy and antegrade endopyelotomy because of the presence of multiple renal stones. Subsequent intravenous pyelography confirmed marked resolution of the obstruction, and both patients remained asymptomatic during 1 year of follow-up

Development and validation of a prediction model for knee joint line orientation after high tibial osteotomy

Background Maintenance of optimal knee joint line orientation (KJLO) is important after high tibial osteotomy (HTO). No tools, however, are currently available that could predict the value of postoperative KJLO before surgery. First, this study sought to determine the effects of various preoperative anatomical alignment parameters to postoperative KJLO. Based upon these analyses, we aimed to devise an equation that predicts the value of postoperative KJLO. Methods A total of 14 radiographic parameters were measured in preoperative and postoperative full-limb standing anteroposterior radiographs on 50 patients who underwent open-wedge HTO. The parameters were analysed using multivariable linear regression to predict KJLO after HTO. External validation of the equation was done with 20 patients who underwent HTO at another institution. Results After HTO, KJLO increased from − 0.8° to 2.9° (P < 0.001). Based on the multivariable linear regression analysis, an equation was derived that can estimate postoperative KJLO after HTO; postoperative KJLO(°) = 1.029 + 0.560 × preoperative KJLO(°) + 0.310 × preoperative tibia plateau inclination(°) + 0.463 × aimed correction angle(°). The adjusted coefficients of determination value for this equation was 0.721. The equation also showed good calibration and predictability in external validation with predicted squared correlation coefficient of 0.867. Conclusions This study analysed the effects of preoperative anatomical alignment parameters on the postoperative KJLO. An equation which predicts postoperative KJLO with preoperative anatomical alignment factors was devised and validated. This equation would help in selecting optimal patients for HTO and in selecting the optimal target correction angle in HTO

Multiple Unilateral Zosteriform Connective Tissue Nevi on the Trunk

Connective tissue nevus is not a true tumor, but rather a hamartoma involving various components of connective tissue. It presents as a slow-growing, painless, flesh-colored, or pink nodule or plaque that is evident from childhood. While any region of the body may be affected, there is a predilection for the trunk and extremities. A 20-month-old girl presented with three ipsilateral confluent popular plaques with zosteriform distribution that had formed over the previous 17 months on the left chest and abdomen. The patient remained asymptomatic. Unlike all previously reported cases demonstrating a single lesion, we report a connective tissue nevi in a child who presented with multiple unilateral zosteriform lesions, an unusual pattern of distribution without evidence of tuberous sclerosis complex