Overcharge protection effect and reaction mechanism of cyclohexylbenzene for lithium ion batteries

We studied the relationship between the structure of aromatic compounds and the overcharge protection effect, using cyclohexylbenzene, isopropylbenzene, and toluene as the overcharge protection agents. Cyclohexylbenzene proved to be the most effective overcharge protection agent among these aromatic compounds. The effect is enhanced using a higher concentration of cyclohexylbenzene and elevated temperatures. The reaction product of cyclohexylbenzene was analyzed using field desorption mass spectrometry to elucidate its reaction mechanism. The results suggested that some of the overcharge reaction products of CHB were more reactive than that of IPB, which is consistent with the better suppressing effect on overcharging of the active material in the positive electrode.     

Improved electrochemical activity of LiMnPO4 by high-energy ball-milling

Olivine lithium manganese phosphate (LiMnPO₄) becomes research focus because of its high energy density and improved thermal stability. However, its application in lithium ion batteries suffers severely from poor electrochemical activity due to low conductivity and structural instability upon the charge and discharge process. By applying a high-energy ball-milling method we succeed in improving the capacity delivery and rate capability. LiMnPO₄ materials ball-milled without or with acetylene black are able to deliver a high capacity of 135 and 127 mAh g⁻¹, respectively, more than 50% greater than the pristine one. Particularly, the latter also shows an improved discharge plateau and stable cyclability. High-energy synchrotron radiation X-ray diffraction (XRD), scanning electron microscopy (SEM), Raman spectroscopy, laser particle analysis, and galvanostatic charge and discharge are employed to understand the effect of ball-milling on the LiMnPO₄ material.     

Index profiling of three-dimensional optical waveguides by the propagation-mode near-field method

The refractive-index profiles of a single-mode fiber and a three-dimensional waveguide are measured by the propagation-mode near-field method. This paper describes the method applied to anisotropic waveguides. The near-field pattern is observed by vidicons, and the index profile is calculated from the measured data. The light transfer characteristic of an infrared vidicon is measured and the intensity data from the infrared vidicon is corrected for the power-law response.     

The concept and potentials of cardiovascular gene therapy

TOPIC: A nursing theory framework for teaching health assessment. PURPOSE: To improve teaching of health assessment and nursing process to beginning-level baccalaureate nursing students. SOURCES: The Assessment and Analysis Guideline Tool, published and unpublished literature, personal observation, and faculty feedback were used in tool development. CONCLUSIONS: Faculty concluded that students who could envision the connection of the Neuman Systems Model and NANDA nursing diagnoses through the nursing process would be better able to understand the nursing model and choose appropriate nursing diagnoses for client care.     

Negative regulation of local hepatocyte growth factor expression by angiotensin II and transforming growth factor-beta in blood vessels: potential role of HGF in cardiovascular disease

BACKGROUND: The death rate for fatal fire accidents in Denmark has doubled since 1951, mostly due to an increase in the number of fire accidents associated with smoking. The most common cause of residential fire deaths in Denmark today is smoking, often combined with alcohol intoxication or handicap. METHODS: This was a case-control study of fatal fire accidents in private homes in the municipality of Copenhagen from 1991 to 1996. The fatal fire accidents were identified from a police register, and the two non-fatal fire accidents registered immediately before and after each fatal fire were selected as a control group. Information about the circumstances surrounding the fires was derived from the police reports. Multivariate logistic regression analysis was used to estimate the risk associated with each variable after adjusting for confounders. The analysis was performed on the basis of the theoretical model in which the variables were part of a causal network. RESULTS: The following five variables seemed to be of most importance: (1) localization of the victim close to the source of ignition (OR = 11), (2) physical handicaps (OR = 5), (3) chronic alcoholism (OR = 7), (4) clothing fires (OR = 24), and (5) alarm being given by a person not present at the scene of fire (OR = 33). Preventive measures are discussed in the light of the results.     

Elevation of the phospholipase A2 activity in peritoneal fluid cells from women with endometriosis

OBJECTIVE: To assess the prostaglandin (PG) production on peritoneal fluid (PF) cells, phospholipase A2 (PLA2) activity of those cells in women with endometriosis was measured and compared with that of women without endometriosis. DESIGN: Prospective clinical controlled study. PATIENTS: Women who underwent laparoscopy and were found either to have endometriosis (n = 15) or not (n = 9) were included in this study. Mononuclear cells obtained from the patients at laparoscopy were immediately separated by a Ficoll-Paque technique, lysed by nitrogen cavitation, and stored at -80 degrees C. INTERVENTIONS: Phospholipase A2 activity was measured by Dole assay using 1-palmitoyl-2-[1-14C] palmitoyl phosphatidyl choline and assessed on a protein basis and a cell number basis. RESULTS: There were at least four measurable kinds of PLA2 activity detected in the cells: two calcium-dependent pH optima 7.0 and 9.0 activities and two calcium-independent pH optima 7.5 and 8.5 activities. A calcium-dependent and pH optima 9.0 activity was the highest, and it was significantly higher in women with endometriosis when compared with those who did not have endometriosis. CONCLUSION: These results indicate that the increase in the PGs in PF with endometriosis may be produced by PF cells in which PLA2 activity is elevated.     

Double exposure stabilization of positive photoresist

Positive photoresists appeared to be the most promising material in VLSI microfabrication for ten or more years from now. Thus, processing know-how needs to be accumulated continuously. This work deals with thermal characteristics of positive photoresist. The following facts were declared experimentally. The quinone diazide, photosensitizer, was thermally decomposed at around 140°C to release N₂. Simultaneously the surface layer of resist film was changed into innert state, called as ‘husk’, with low gas permeability and high chemical resistance. These thermal changes in resist film affect the photoresist to SiO₂ adhesion. In this work a noble process, named double exposure stabilization, is developed to get sufficient chemical resistance and good adhesion simultaneously.     

A patch technique for reconstruction of stenotic pulmonary bifurcation in a Rastelli-type operation after palliations for cyanotic congenital heart disease. A report of two cases

A Rastelli-type operation was successfully performed on two patients with cyanotic congenital heart disease with pulmonary artesia (PA) and severe stenosis or obstruction of the pulmonary bifurcation, following the improvement of a pulmonary artery index (PA index) after palliative systemic pulmonary shunts. It is a point that stenotic or obstructive pulmonary bifurcation was reconstructed by a patch technique. An extracardiac conduit was used a combination of a bicuspid valved pericardial roll and a prosthetic vessel graft. In a 5-year-old male with an extreme type of tetralogy of Fallot associated with PA and patent ductus arteriosus (PDA), the enlargement of stenotic pulmonary bifurcation was attempted using a brimshaped equine pericardial patch in order to get sufficient suture margin and be safely anastomosed with a conduit. In a 6-year-old female with complete transposition of the great arteries, PA, PDA and right aortic arch (RAA), an obstructive pulmonary bifurcation behind the RAA was enlarged using a brimshaped equine pericardial patch. The attachment of the conduit was shifted to the left pulmonary artery to avoid compression of an extracardiac conduit and pulmonary artery behind RAA. Reconstruction of the pulmonary bifurcation using an equine pericardial patch is useful to anastomose an extracardiac conduit and the stenotic or obstructive pulmonary bifurcation.     

Resonant Rutherford backscattering. Study ofa-axis YBaCuO films with very high crystallinity

Hybrid sputtering and the conventional dc-template sputtering methods were used to deposit highly crystallinea-axis films. The oxygen contents and disorder of the films were measured by the resonant Rutherford backscattering. The oxygen content of the films deposited by the hybrid sputtering depend on the deposition temperature. Films deposited at a low temperature have low oxygen content. The poor superconducting properties of these films may be due to the oxygen deficiency. The stoichiometry of the films deposited by the dc-template sputtering method was found to depend on the microstructure of the template. The disorder at the Ba and O sublattices of these highly crystallinea-axis films are uncorrelated.     

The effect of pre-oxidation atmosphere on the durability of EB-PVD thermal barrier coatings with CoNiCrAlY bond coats

The effects of pre-oxidation heat treatment on oxidation behavior and thermal cycle life of electron-beam physical deposited (EB-PVD) thermal barrier coatings (TBCs) with CoNiCrAlY bond coats were investigated as a function of the pO₂ of the pre-oxidation atmosphere. The pO₂ of the pre-oxidation atmosphere was controlled by using a solid-state electrochemical oxygen pump system. The purity and microstructure of the continuous Al₂O₃ layer formed on the bond coat during pre-oxidation at 1050 °C were highly influenced by the pO₂ of the atmosphere. High purity α-Al₂O₃ with large grain size was formed on the bond coats under a pO₂ of 10^− 12-10^− 9 Pa, which resulted in a lower growth rate of TGO and longer lifetime.