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Two new zinc coordination polymers, {[Zn(iPrIPA)(bpa)]⋅2H2O}n (1) and [Zn2(iPrIPA)2(bpp)]n (2) (iPrIPA = 5-i-propoxyisophthalate, bpa = 1,2-bis(4-pyridyl) ethane, bpp = 1,3-bis(4-pyridyl)propane), have been synthesized under hydrothermal conditions. Complexes 1 and 2 represent 3-D polythreaded supra molecular architecture consisting of corrugated 2D layer for complexes 1 and a 2D network consisting of alternating Zn1 binuclear and paddel-wheel Zn2 binuclear units for compound 2. The structural comparison of these two complexes demonstrates that the characteristics of auxiliary ligands play a key role in governing the coordination motifs and the final supramolecular lattices. Fluorescence emission and room temperature phosphorescence (RTP) behavior of 1 and 2 were also investigated. [ABSTRACT FROM AUTHOR]

Industrial activities discharge a large amount of wastes containing hexavalent chromium [Cr(VI)] into the environment, which poses a threat to human health. Microorganisms can be used as efficient tools for Cr(VI) remediation. In this study, the Cr(VI) removal capacity of Aspergillus niger was evaluated. A. niger could tolerate and reduce Cr(VI) by nearly 100% at concentrations ranging from 10 to 50 mg/L. Overall, almost 97% of the Cr(VI) removal was caused by extracellular reduction whereas 3% was caused by accumulation. Extracellular reduction was mediated by non-enzymatic cell secretions, whereas extracellular accumulated Cr formed precipitates on the hyphal surfaces and was partially absorbed on the cell wall. Cr(VI) also entered the cell and was reduced by the strong chromate reductase activity in cell-free extracts and then accumulated within the cell. These data suggest that A. niger, which has the capacity to remove Cr(VI) by reduction and accumulation, can be a useful tool for Cr(VI) remediation. [ABSTRACT FROM AUTHOR]

Background: Numerous metabolic parameters can be changed during hemodialysis in the end-stage renal disease (ESRD) caused by systemic diseases, such as diabetes mellitus, hypertension. Some ocular parameters also can be variable due to the changes after hemodialysis. This study evaluates the effects of ocular parameters, including best-corrected visual acuity (BCVA), intraocular pressure (IOP), central macular thickness (CMT), subfoveal choroidal thickness (SFCT), retinal arteriolar caliber (RAC), retinal venular calibre (RVC), in ESRD patients following hemodialysis. Materials and methods: Two-hundred and two ESRD patients were recruited resulting in 404 eyes evaluations. All patients underwent hemodialysis in the Dialysis Unit of the Second Hospital of Tianjin Medical University. BCVA, CMT, IOP, SFCT, RAC and RVC were evaluated before and after hemodialysis. Systemic parameters were collected such as age, body weight, systolic blood pressure (SBP), diastolic blood pressure (DBP), duration of hemodialysis, body weight changes, high density lipoprotein cholesterol (HDLC), low density lipoprotein cholesterol (LDLC), very low density lipoprotein cholesterol (VLDLC), glycosylated hemoglobin (HbA1c). Results: The causes of ESRD patients included chronic glomerulonephritis (n = 65), diabetes mellitus (n = 60), hypertensive nephrosclerosis (n = 37), and other causes (n = 40). In our study, BCVA (p =.817), CMT (p =.252) and IOP (p =.978) did not significantly change after hemodialysis. SFCT significantly decreased from 254.29 ± 69.36 μm to 235.54 ± 659.90 μm (p =.002) following hemodialysis. SFCT changes were significantly correlated with SBP (p =.042) and body weight changes (p =.044). The RAC and RVC were dilated significantly (p =.033, p =.007). RVC changes were correlated with baseline DBP (p =.003), HDLC (p =.009), LDLC (p =.004) and changes in DBP (p =.037) and body weight (p =.001). Conclusion: Hemodialysis can affect various ocular parameters including SFCT, RAC and RVC, which changed significantly following hemodialysis. Whereas BCVA, IOP and CMT did not change after hemodialysis in ESRD patients. The systemic compensatory mechanisms of the changes in SBP, DBP, body weight following hemodialysis need further study. [ABSTRACT FROM AUTHOR]

Lead is a major source of environmental pollution that has recently been the focus of a great deal of research. Bioremediation has been shown to be effective in remediation of lead pollution. Penicillium polonicum is a fungus with highly efficient adsorption of lead. In this study, the influence of electric current on the growth characteristics and adsorption of lead by the strain were investigated through applying different external voltages (1.5, 1.25, 1.0, 0.75, and 0.5 V). The results indicated that the electric current with voltage ranges from 1.0 to 1.25 V could promote the adsorption of lead. In addition, morphological characteristics and the quantity of lead-containing minerals formed on the surface of P. polonicum differed greatly under different experimental conditions. Further, the electric current intensity and electric energy consumption at voltages of 1.0, 1.25, and 1.5 V were higher than the blank control group, suggesting that the strain could utilize the energy supplied by an external electrochemical workstation to improve lead adsorption. After applying an external current, the lead adsorption of P. polonicum was affected by electric current changing the growth environment of the fungus and the electron transfer reaction between electrodes and P. polonicum. [ABSTRACT FROM AUTHOR]

Lead pollution is rapidly becoming a serious concern, and remediation of lead contamination is a major challenge. Biological remediation is both environmentally friendly and sustainable process. In this study, we investigated the application of Aspergillus niger (Bpb1) for removing lead ion from a liquid medium by using photoelectron generated from a light-semiconductor mineral-microbial system. Synthetic anatase electrodes were systematically characterized and used as a photoelectron provider. Under light irradiation, the adsorption rates of Pb(II) by A. niger in the experimental groups increased by 204% (the maximum) on the fourth day, while the total adsorption rates remained the same. Further study of lead products revealed that lead ion combines with organic acids to form extracellular lead-containing products, which wrap around the fungal hyphae and combine with the cell wall. The anatase photoelectron enhanced the adsorption rate of Pb(II) by A. niger by forming larger lead-containing products, and by accelerating the transportation of Pb(II) into the inner cell. This novel approach provides newer insights into the application of biological degradation for environmental remediation. [ABSTRACT FROM AUTHOR]

A novel phase change microcapsule with compound crust is briefly introduced in this paper, and the heat transfer enhancement due to a microencapsulated phase change material is investigated parametrically for laminar convective heat transfer in a circular tube with constant wall temperature. The size of the phase change mushy region and the phase change interface locations are given for the various governing parameters. Two enhancement ratios, the traditional enhancement ratio and a modified enhancement ratio, were used to quantify the enhanced heat transfer characteristics of the microencapsulated phase change suspension for six major parameters. The six parameters are the bulk Stephan number, the volumetric concentration of the solid-phase, the particle-to-tube radius ratio, the dimensionless initial subcooling, the dimensionless phase change temperature range, and the bulk Reynolds number. The simulations show that the bulk Stephan number and the volumetric concentration are the most important parameters influencing the heat transfer enhancement of the microencapsulated suspension. The influence of the microcapsule diameters on the heat transfer enhancement comes from the microconvection, instead of the latent heat release due to the phase change. In addition, the combined effect of changes in all of these parameters on the heat transfer enhancement was examined. [ABSTRACT FROM AUTHOR]

A D-shaped photonic crystal fibre filled with liquid crystal was demonstrated as an amphibious sensor for detection of both temperature and refractive index, when combined with plasma materials. Specifically, the optical component is implanted into a complete optical system ensuring modulation of the external electric field. When the refractive index of the external solution changes from 1.0 to 1.6, the y-polarised mode has a loss spectrum with a wavelength sensitivity of up to 2275 nm/RIU, and the corresponding amplitude sensitivity is −88.2RIU−1. When the perceived temperature changes from 15°C to 50°C, the temperature of the sensor is correspondingly expressed as the maximum wavelength sensitivity of 9.09 nm/°C and the amplitude sensitivity of −0.311°C−1. In addition, the actual micro-operation processes have been studied in detail, such as polishing depth, coating thickness and coating method. This provides practical ideas for real-time sensing analysis that requires harsh environments. [ABSTRACT FROM AUTHOR]