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Effects of solar panels must be taken into account by the light intensity of its output characteristics in practical application, especially solar panels placed outdoor. So the light intensity coefficient is an important parameter to be considered. In this paper,we took the light intensity characteristics of single crystal silicon solar cell as the research object. Also,through transforming the illumination intensity which are 777.60W/m2,996.97 W/m2 and 1224.88 W/m2, we would finish researching the characteristics of the cell sheet, which included battery plate volt ampere characteristic, open circuit voltage, short circuit current and maximum output power. Also, we’ve got the relationship of Uoc-T, Isc-T and Pm-T, respectively and Put forward the better intensity theory. It would lay a solid foundation of practice for the further study on how to improve the rate of light conversion.

This study describes an analytical method employing capillary gas chromatography (GC) using flame ionization detection (FID) that has been developed for the simultaneous determination of food preservatives in drinks, including sorbic acid (SA), benzonic acid (BA) and methyl paraben (MP). For this purpose, dispersive liquid-liquid microextraction (DLLME) was applied as a sample preparation technique. The DLLME conditions such as the types and volume of extraction solvent, the types and volume of the disperser solvent, pH value and salt addition were investigated and optimized. The method was linear in the ranges from 0.5 to 100.0 μg·mL-1for abovementioned preservatives withR2≥ 0.9991. The DLLME procedure allowed efficient recovery of the analyted preservatives ranging between 91 % and 108 % with a relative standard deviation (RSD) ≤ 6.1 for the blank samples spiked with 20, 40 and 80 μg·mL-1of preservatives, respectively. The developed procedure was demonstrated to be a effective method for the analysis of preservatives in drinks. Furthermore, the method is simple, reproducible, envioronmentally friendly and inexpensive.

An novel Lead (II)-dithizone-xylenol orange tenary complex spectrophotometry was developed for the determination of Pb2+ in wastewater. For this purpose, the parameters of spectrophotometry such as the detection wavelength, pH value, the dosage of dithizone-xylenol orange and reaction time were studied and optimized through orthogonal tests. The method was linear in the ranges from 2.1×10-3 to 6.0 μg·mL-1 for Pb2+ with R2≥ 0.999. The procedure allowed efficient recovery of the investigated Pb2+ ranging between 95 % and 103 % with a relative standard deviation (RSD) ≤ 2.1 for actual wastewater samples spiked with 1.00, 2.00 and 3.00 μg·mL-1 of standard Pb2+, respectively. These results show the method can be applied to the direct determination of Pb2+ in wastewater, avoiding the use of toxic extrant (chloroform) and masking reagent (sodium cyanide) in the traditional methods and time-consuming procedures, moreover, the investigated method is simple, accurate, reliable, and inexpensive, which implies the potential of this technique for Pb2+ monitoring in wastewater samples.

A simple and reliable method combining dispersive liquid-liquid microextracion (DLLME) with gas chromatography (GC) using flame ionization detection (FID) was developed for the simultaneous determination of aniline (AL),o-toluidine (o-TLD),N,N-dimethylaniline (N,N-DAL),p-chloroaniline (p-CAL), andp-nitroaniline (p-NAL) in wastewater. For this purpose, dispersive liquid-liquid microextraction (DLLME) was applied as a sample preparation technique. The DLLME conditions such as the types and volume of extraction solvent, the types and volume of the disperser solvent, pH value and salt addition were studied and optimized. The method was linear in the ranges from 2.2×10-3to 100.0 μg·mL-1for aforementioned aromatic amines withR2≥ 0.9968. The DLLME procedure allowed efficient recovery of the investigated aromatic amines ranging between 82 % and 92 % with a relative standard deviation (RSD) ≤ 3.4 for actual wastewater samples spiked with 5, 10 and 20 μg·mL-1of aromatic amines, respectively. These results showed the potential of this technique for aromatic amines monitoring in wastewater samples. Furthermore, the investigated methods are simple, reproducible, and inexpensive.

This study describes an analytical method employing capillary gas chromatography (GC) using flame ionization detection (FID) that has been developed for the simultaneous determination of acrylates (methyl acrylate (MA), methyl methacrylate (MMA), butyl acrylate (BA)) in wastewater. For this purpose, dispersive liquid-liquid microextraction (DLLME) was applied as a sample preparation technique. The DLLME conditions such as the types and volume of extraction solvent, the types and volume of the disperser solvent, pH value and salt addition were studied and optimized. The method was linear in the ranges from 4.3×10-4 to 200.0 μg·mL-1 for abovementioned acrylates with R2≥ 0.9992. The DLLME procedure allowed efficient recovery of the investigated acrylates ranging between 81 % and 109 % with a relative standard deviation (RSD) ≤ 9.1 for the blank samples spiked with 10, 50 and 100 μg·mL-1 of acrylates, respectively. These results showed the potential of this technique for acrylates monitoring in wastewater samples. Furthermore, the investigated methods are simple, reproducible, and inexpensive.

This study describes an analytical method employing capillary gas chromatography (GC) using flame ionization detection (FID) that has been developed for the simultaneous determination of polycyclic aromatic hydrocarbons (PAHs) in wastewater, including naphthalene, 1-naphthol, 2-naphthol and anthracene. For this purpose, single-drop microextraction (SDME) was applied as a sample preparation technique. The SDME parameters such as types of extractants, volume of the microdroplet size, extraction time, stir rate and immersion depth of needle point were investigated and optimized. The method was linear in the ranges from 2.3 ×10-3to 70.0 μg·mL-1for naphthalene, 1-naphthol and anthracene, and 2.2 ×10-3to 50.0 μg·mL-1for 2-naphthol withR2≥ 0.9990. The SDME procedure allowed efficient recovery of the investigated PAHs ranging between 94 % and 104 % with a relative standard deviation (RSD) ≤4.2 for actual wastewater sampes spiked with 5, 10 and 20 μg·mL-1of PAHs, respectively. These results showed the potential of this technique for PAHs monitoring in wastewater samples. Furthermore, the investigated methods are simple, reliable, reproducible, and not expensive.

This study describes an analytical method employing capillary gas chromatography (GC) using flame ionization detection (FID) that has been developed for the simultaneous determination of chlorobenzenes (m-dichlorobenzene (m-DCB),p-dichlorobenzene (p-DCB),o-dichlorobenzene (o-DCB) and 1,2,4-trichlorobenzene (1,2,4-TCB)) in wastewater. For this purpose, single-drop microextraction (SDME) was applied as a sample preparation technique. The SDME parameters such as types of extractants, volume of the microdroplet size, extraction time, stir rate and immersion depth of needle point were studyed and optimized. The method was linear in the ranges from 4.0×10-3to 40.0 μg·mL-1form-DCB,p-DCB ando-DCB, and 4.0×10-3to 30.0 μg·mL-1for 1,2,4-TCB withR2≥0.9955. The SDME procedure allowed efficient recovery of the investigated chlorobenzenes ranging between 80 % and 105 % with a relative standard deviation (RSD) ≤6.5 for actual wastewater sampes spiked with 2, 5 and 10 μg·mL-1of chlorobenzes, respectively. These results showed the potential of this technique for chlorobenzenes monitoring in wastewater samples. Furthermore, the investigated methods are simple, reliable, reproducible, and not expensive.

Single-drop microextraction (SDME) coupled to capillary gas chromatography (GC) was established for the determination of seven volatile halogenated hydrocarbons in wastewater, including chloroform (CF), carbon tetrachloride (CT), trichloroethylene (TCE), bromodichloromethane (BDCM), perchlorethylene (PCE), dibromochloromethane (DBCM) and bromoform (BF). The SDME parameters such as extractants, extracting time，stirring rate and immerging depth of needle point were studyed and optimized. The abovementioned halogenated hydrocarbons were quantified by external standardization method using GC coupled with a flame ionization detector (FID). The linear regression calibration curves, detection limits (S/N=3) and the linear ranges of the method for determining each halogenated hydrocarbons were determined, respectively. The concentrations of componds abovementioned in a real wastewater sample, the average of the recoveries obtained in the spiked wastewater samples and the corresponding relative standard deviations were determined, respectively. The results showed the proposed method several attributes, friendly enviroment, economic and highly efficient pretreatment, less time, simplicity, sensitivity, accuracy and wide linear range and so on.

The overlapping chromatograms and spectra of sulfonamides, sulfadiazine (SD) and sulfamethoxazole (SM) in both synthetic samples and pharmaceutical tablets in the presence of uncalibrated and interfering sulfanilamide (SN) were resolved by HPLC-DAD combined with SWATLD algorithm. The elution time was set from1.077 min to 1.624 min and the detection wavelength was chosen from 230 nm to 316 nm. The recoveries of SD and SM were (98.1 ± 4.8)% and (100.1 ± 1.6)%, respectively. The satisfying results show this method can be easily performed and applied to solving second-order calibration problems quickly and accurately.

The highly overlapping chromatograms and spectra of the major metabolites of asprin, salicylic acid (SA) and gentisic acid (GA) in the presence of uncalibrated and interfering pyrocatechuic acid (PA) were resolved using HPLC-DAD combined with SWATLD algorithm. The elution time was set from 0.6628 min to 0.9495 min and the detection wavelength was chosen from 268 nm to 332 nm. Both SA and GA were determined simultaneously in aqueous solution with their recoveries were (100.5 ± 6.7) % and (109.2 ± 5.3) %, respectively. The satisfying results indicate this method can be easily performed and applied to solving second-order calibration problems quickly and accurately.

The overlapped chromatograms and spectra of sulfadiazine (SD) and sulfamethoxazole (SM) in both synthetic samples and pharmaceutical tablets even in the presence of uncalibrated and interfering sulfanilamide (SN) were resolved by HPLC-DAD combined with a novel second-order calibration method. Their elution time was set from1.077 min to 1.624 min and the detection wavelength was chosen from 230 nm to 316 nm. The recoveries of SD and SM were (99.3 ± 1.3)% and (99.2 ± 3.1)%, respectively. The satisfying results show this method can be easily performed and applied to solving second-order calibration problems quickly and accurately.

The highly overlapped chromatograms and spectra of salicylic acid (SA), gentisic acid (GA) and uncalibrated interferent, pyrocatechuic acid (PA) were resolved using HPLC-DAD combined with a novel second-order calibration method. Their elution time was set from 0.6628 min to 0.9495 min and the detection wavelength was chosen from 268 nm to 332 nm. Both SA and GA were determined simultaneously in aqueous solution with their recoveries were (101.0 ± 7.1) % and (105.8 ± 5.6) %, respectively. The satisfying results demonstrate this method can be easily performed and applied to solving second-order calibration problems quickly and accurately.

Flaky and porous rod-like MgO powders were prepared by molten salt synthesis with MgCl2, CaCO3, NaNO3and KNO3as raw materials. TG-DSC, XRD and SEM were used to investigate the reacion process and characterize the resulting products. The results indicated that Ca2+was displaced by Mg2+and dolomites were formed and finally converted into magnesium carbonates during the molten salt synthesis. Fibrous Mg(OH)2formed in PEG solution and flaky Mg(OH)2formed in EDTA-PEG solution illustrated that EDTA and PEG molecules could define the growth direction of Mg(OH)2. The porous rod-like MgO powders with 20-80 nm in diameter and 40-100 in length-to-width ratio were obtained by the decomposition of fibrous Mg(OH)2at 600 °C, while the flaky MgO powders were prepared by the decomposition of flaky Mg(OH)2at 600 °C. Flaky MgO powders were platelike, with 30-50 nm in thickness, 200-500 nm in diameter, and up to 1.0 µm2in a single slice surface area.

An Internal Circulation Impinging Stream Biofilm Reactor (ICISBR) was developed and used for treatment synthetic organic wastewater with corncob as biofilm carriers. Effects of COD loading rates and aeration rates on COD removal and DO contents were investigated. COD removal efficiency increased together with effluent COD with increasing COD loading rates. As the aeration rate was increased, the DO content also increased together with COD removal efficiency up to an optimum aeration rate of 0.3m3h-1. Beyond this optimum aeration rate a significant decrease in DO content and COD removal efficiency were experienced. This study could provide theoretic basis for the ICISBR treating organic wastewater.

The emu, a large bipedal bird with hip joint biomechanics similar to humans, was used to establish an experimental model of femoral head osteonecrosis and subsequent femoral head collapse. Focal lesions were induced in 20 adult male emus using an alternating liquid nitrogen freezing and radiofrequency heating insult. At 2, 4, 8, 12 and 16 weeks post-surgery, hip magnetic resonance imaging (MRI) was performed. Before the emus were sacrificed, barium sulphate was infused to the lower extremity to study blood vessel distribution patterns. Femoral samples were scanned by micro-computed tomography (micro-CT) and evaluated histologically. Hip MRI showed changes from broad oedema to femoral head collapse. Emus developed a crippled gait from post-operative week 6. Micro-CT scans and histology showed human-like osteonecrotic changes with an impaired local blood supply. The protocol resulted in consistent full-range osteonecrosis of the femoral head that may serve as a model for testing potential treatments.

To establish a new animal model of osteonecrosis of the femoral head(ONFH) with improved consistency and incidence of femoral head collapse for studies on the mechanism of osteonecrosis. and on the assessment of treatment effectiveness.Twenty adult male emus were used. Guide instrumentation was constructed to position the customized probe just articularly and at the proximal part of the femoral head. An alternating focal liquid nitrogen freezing and radiofrequency heating was applied. At 2, 4, 8, 12 and 16 weeks after surgery, hip magnetic resonance imaging (MRI) was performed. Before the emus were sacrificed, barium sulfate was infused to lower extremities for microangiography. The femoral samples were scanned by micro-computed tomography (Micro-CT) and evaluated histologically.No bird demonstrated signs of infection or died unexpectedly. Hip MRI showed changes massive edema at the 4th week, increasingly localized abnormal signals at the 8th'" week, and femoral head collapse at the 12'h week. Micro-CT scans and histological images at the 16th week showed human-like osteonecrotic changes with impaired local blood supply. Bone mineral density of the collapsed head was (380. 31 + 28. 12) mg/cm3 and trabecular spaces were (0. 86 ±0.32) mm; both were significantly lower than those in the control side, which were (415.75 41.28) mg/cm3 and (1. 17 ± 0. 17) mm, respectively (P0. 05). Bone volume fraction of the collapsed head was(47.28 ± 17. 14)% and trabecular thickness was (506. 17 ± 220. 58) p.m; both were significantly higher than those at control side, which were (30. 92 ± 4. 01)% and (325. 50 ±44. 53) pm, respectively (P0. 05). The microangiography at the 16th week showed that vessel volume fraction was (0. 315 ± 0. 055)% , which was significantly higher than the collapsed side [ (0. 142 ± 0. 059)% ] (P0. 05).The emu model of fem-oral head osteonecrosis was successfully established using focal alternating cooling and heating insults. The models, with improved consistency and incidence of femoral head collapse, can be used in studies on the mechanism of osteonecrosis and on the assessment of treatment effectiveness.

Alternating trilinear decomposition (ATLD) algorithm is a promising method for second-order calibration, which is based on an alternating least-squares principle to overcome some shortcomings of the traditional parallel factor analysis (PARAFAC) algorithms, such as the sensitivity to the estimated component numbers and slow convergence. It utilizes an iterative procedure involving Moore-Penrose generalized inverse computations based on singular value decomposition and can be applied to the simultaneous determination of several organic components even in the presence of unknown interfering components. The overlapped chromatogram and spectra system of dihydroxybenzenes were resolved by ATLD combined with reversed-phase high performance liquid chromatography (RP-HPLC)/ diode array detection (DAD). The elution time was set from 1.086 min to 1.399 min with an interval of 1/150 min and the ultraviolet wavelength from 268 nm to 298 nm with an interval of 1 nm. The resolved results were in agreement with the actual results excellently. Catechol (CAT), resorcinol (RES) and hydroquinone (HYD) in aqueous solution were determined simultaneously, whose recoveries were (100.1 +/- 1.0)%, (99.4 +/- 1.4)% and (100.5 +/- 1.7)%, respectively. The results showed this experiment can be easily performed without resorting to time-consuming and complicated procedures and quantified accurately. It successfully solved the resolving problem caused by chromatogram and spectra overlapping in the presence of interfering components. It also revealed the ATLD algorithm can be efficiently applied to solve the second-order calibration problem in HPLC-DAD.