Room-temperature fast construction of outperformed ZnO nanoarchitectures on nanowire-array templates for dye-sensitized solar cells.

A ZnO nanoarchitecture composed of nanocactus (NCs) and nanosheets (NSs) is constructed on the ZnO-nanowire (NW)-array template within 4 min by a facile room-temperature (RT) chemical bath deposition (CBD) for use in dye-sensitized solar cells (DSSCs). Compared to the ZnO NW array, the spines and shells of NCs provide larger and more fitting surface for dye adsorption. The NSs developed on the top and side walls of the NWs afford the additional surface for dye adsorption as well as for light scattering. Moreover, the RT-grown ZnO nanostructures possess an upward-shifted conduction band edge and a fast electron transport rate compared to the primary ZnO NW array. With an anode thickness of 9 µm, an efficiency of 5.14% is therefore simply attained in the D149-sensitized ZnO NC-NS DSSC.

Investigation of charge transfer in Au nanoparticle-ZnO nanosheet composite photocatalysts.

Ohmic contact formation at the interface of the Au nanoparticle (NP)-ZnO nanosheet (NS), which facilitates photoelectron transfer from ZnO NSs to Au NPs, is determined by scanning Kelvin microscopy for the first time. Reduction of charge recombination in the ZnO NSs confirmed by the quench of green band emission results in the enhancement of photocatalytic activity of the Au NP-ZnO NS composite.

Intraosseous leiomyoma of the distal femur: a case report and review of literatures.

BACKGROUND: Leiomyoma is a benign tumor of smooth-muscle origin. They most commonly derived from the uterus. Besides, they were also usually diagnosed in the gastrointestinal tract, skin, and mucous membranes. However, it rarely occurs in the bone. CASE PRESENTATION: The authors reported one case of 56-year-old male with intraosseous leiomyoma of the distal femur. Initially, the patient felt left knee pain for 1 year. Radiographs film disclosed an ill-defined osteolytic lesion with thinning cortex over left distal femoral medial condylar region. Computed tomography (CT) revealed homogenous radiolucent lesion with thinning cortex over the metaphysis of distal femur. Magnetic resonance imaging showed focal marrow replacement by tumor. CT-guide biopsy was performed, and the pathology showed a picture of leiomyoma. Since the definite diagnosis, the lesion was treated with en-bloc resection and endoprosthetic knee joint reconstruction. Satisfied result and disease free were achieved during follow-up. CONCLUSIONS: Intraosseous leiomyoma of the extremities is difficult to be diagnosed due to extraordinarily rare. This rare benign tumor should be included in the differential diagnosis of any relatively intraosseous lesion with benign imaging findings. This is the first published case of primary intraosseous leiomyoma of distal femur after literature reviews.

Determination of diphenylether herbicides in water samples by solid-phase microextraction coupled to liquid chromatography.

Solid-phase microextraction (SPME) coupled to LC for the analysis of five diphenylether herbicides (aclonifen, bifenox, fluoroglycofen-ethyl, oxyfluorfen, and lactofen) is described. Various parameters of extraction of analytes onto the fiber (such as type of fiber, extraction time and temperature, pH, impact of salt and organic solute) and desorption from the fiber in the desorption chamber prior to separation (such as type and composition of desorption solvent, desorption mode, soaking time, and flush-out time) were studied and optimized. Four commercially available SPME fibers were studied. PDMS/divinylbenzene (PDMS/DVB, 60 microm) and carbowax/ templated resin (CW/TPR, 50 microm) fibers were selected due to better extraction efficiencies. Repeatability (RSD, < 7%), correlation coefficient (> 0.994), and detection limit (0.33-1.74 and 0.22-1.94 ng/mL, respectively, for PDMS/DVB and CW/TPR) were investigated. Relative recovery (81-104% for PDMS/DVB and 83-100% for CW/TPR fiber) values have also been calculated. The developed method was successfully applied to the analysis of river water and water collected from a vegetable garden.

Analysis of earthy and musty odors in water samples by solid-phase microextraction coupled with gas chromatography/ion trap mass spectrometry.

A method for the determination of the earthy and musty odors geosmin, 2-methylisoborneol (2-MIB), 2-isobutyl-3-methoxy pyrazine (IBMP), 2-isopropyl-3-methoxy pyrazine (IPMP) and 2,4,6-trichloroanisole (2,4,6-TCA) in water by headspace solid-phase microextraction (HSSPME) combined with gas chromatography-ion trap mass spectrometry (GC-ITMS) is described. Several parameters of the extraction and desorption procedure were studied and optimized (such as types of fibers, extraction temperature, extraction time, desorption temperature, desorption time, ionic strength and elutropic strength and pH of samples). The method shows good linearity over the concentration range 1-500ngl(-1) and gives detection limits of sub-part per trillion levels for all compounds. Good precision (5.9-9.8%) is obtained using IBMP as internal standard. Finally, the method was successfully applied to analyze earthy and musty odors in tap water and lake water.

Direct and simultaneous determination of arsenic, manganese, cobalt and nickel in urine with a multielement graphite furnace atomic absorption spectrometer.

A simple method was developed for the direct and simultaneous determination of arsenic (As), manganese (Mn), cobalt (Co), and nickel (Ni) in urine by a multi-element graphite furnace atomic absorption spectrometer (Perkin-Elmer SIMAA 6000) equipped with the transversely heated graphite atomizer and longitudinal Zeeman-effect background correction. Pd was used as the chemical modifier along with either the internal furnace gas or a internal furnace gas containing hydrogen and a double stage pyrolysis process. A standard reference material (SRM) of Seronormtrade mark Trace Elements in urine was used to confirm the accuracy of the method. The optimum conditions for the analysis of urine samples are pyrolysis at 1350 degrees C (using 5% H(2) v/v in Ar as the inter furnace gas during the first pyrolysis stage and pure Ar during the second pyrolysis stage) and atomization at 2100 degrees C. The use of Ar and matrix-free standards resulted in concentrations for all the analytes within 85% (As) to 110% (Ni) of the certified values. The recovery for As was improved when mixture of 5% H(2) and 95% Ar (v/v) internal furnace gas was applied during the first step of a two-stage pyrolysis at 1350 degrees C, and the found values of the analytes were within 91-110% of the certified value. The recoveries for real urine samples were in the range 88-95% for these four elements. The detection limits were 0.78mugl(-1) for As, 0.054mugl(-1) for Mn, 0.22mugl(-1) for Co, and 0.35mugl(-1) for Ni. The upper limits of the linear calibration curve are 60mugl(-1) (As); 12mugl(-1) (Mn); 12mugl(-1) (Co) and 25mugl(-1) (Ni), respectively. The relative standard deviations (R.S.D.s) for the analysis of SRM were 2% or less. The R.S.D.s of a real urine sample are 1.6% (As), 6.3% (Mn), 7.0% (Ni) and 8.0% (Co), respectively.

Analysis of triazine in water samples by solid-phase microextraction coupled with high-performance liquid chromatography.

Solid-phase microextraction (SPME) coupled with high-performance liquid chromatography (HPLC) for the determination of triazine is described. Carbowax/templated resin (CW/TPR, 50mum), polydimethylsiloxane/divinylbenzene (PDMS/DVB, 60mum), polydimethylsiloxane (PDMS, 100mum), and polyacrylate (PA, 85mum) fibers were evaluated for extraction of the triazines. CW/TPR and PDMS/DVB fibers were selected for further study. Several parameters of the extraction and desorption procedure were studied and optimized (such as types of fibers, desorption mode, desorption time, compositions of solvent for desorption, soaking periods and the flow rate during desorption period, extraction time, temperature, pH, and ionic strength of samples). Both CW/TPR and PDMS/DVB fibers are acceptable; a simple calibration-curve method based on simple aqueous standards can be used. The linearity of this method for analyzing standard solution has been investigated over the range 5-1000ngmL(-1) for both PDMS/DVB and CW/TPR fibers. All the correlation coefficients in the range 5-1000ngmL(-1) were better than 0.995 except Simazine and Atratone by CW/TPR fiber. The R.S.D.s range from 4.4% to 8.8 % (PDMS/DVB fiber) and from 2.4% to 7.2% (CW/TPR fiber). Method-detection limits (MDL) are in the range 1.2-2.6 and 2.8-3.4ngmL(-1) for the two fibers. These methods were applied to the determination of trazines in environmental water samples (lake water).

Solid-phase microextraction coupled with high-performance liquid chromatography for the determination of phenylurea herbicides in aqueous samples.

Solid-phase microextraction coupled with high-performance liquid chromatography was successfully applied to the analysis of nine phenylurea herbicides (metoxuron, monuron, chlorotoluron, isoproturon, monolinuron, metobromuron, buturon, linuron, and chlorbromuron). Polydimethylsiloxane-divinylbenzene (PDMS-DVB, 60 microm) and Carbowax-templated resin (CW-TPR, 50 microm) fibers were selected from four commercial fibers for further study because of their better extraction efficiencies. The parameters of the desorption procedure were studied and optimized. The effects of the properties of analytes and fiber coatings, carryover, duration and temperature of absorption, pH, organic solvent and ionic strength of samples were also investigated. External calibration with an aqueous standard can be used for the analysis of environmental samples (lake water) using either PDMS-DVB or CW-TPR fibers. Good precisions (1.0-5.9%) are achieved for this method, and the detection limits are at the level of 0.5-5.1 ng/ml.