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Most studies have concentrated on the distribution of polycyclic aromatic hydrocarbons (PAHs) in air, water, and soil; however, little is known about their behavior during urban wet deposition. During frequent urban rainstorms, surface runoff carries large amounts of organic pollutants into water, which has a significant impact on the quality of the water environment. “Poseidon” made landfall in Jilin Province on 27 August, 3 September, and 7 September 2020, respectively, causing some impact on the surface water. Gas chromatography–mass spectrometry (GC–MS) was used to measure the concentrations of 16 major PAHs in stormwater and water samples from the Yitong River. The PAH concentrations in rainwater runoff gradually decreased with increasing rainfall duration. The PAHs in the Yitong River water samples were mainly composed of two to three rings, with total concentrations ranging 279.19–756.37 ng/L. Ratio characterization and principal component analysis of the sources of PAHs in the water samples revealed that some water bodies had also been contaminated by oil spills in addition to combustion emissions from coal and motor vehicle oil. Health and environmental risks were assessed for PAHs in water bodies from the Yitong River, and health risk assessment showed that exposure to PAHs in the water is not a health risk for human beings; however, the risk for children is higher than that for adults and requires attention. Although the environmental risk is moderate, the risk from Benzo(a)anthracene(BaA) alone is high and requires ongoing attention. In terms of the sustainability of drinking water sources, consideration should be given to taking necessary regulatory and protective measures to prevent further contamination. These results serve as a guide for managing PAHs in urban water bodies and managing water pollution.

A municipal wastewater treatment plant plays an important role in treating urban sewage and reducing the quantity of pollutants discharged into rivers. However, the energy consumption of the municipal wastewater treatment industry is large. High energy consumption indirectly produces ecological damage, accelerates the energy crisis, and increases carbon emissions. For energy conservation and emission reduction in wastewater treatment plants, it is first necessary to identify the main factors influencing energy consumption. Electricity consumption accounts for more than 80% of the energy consumption of wastewater treatment plants. Wastewater quantity and wastewater quality have become the key influencing factors of energy conservation and consumption reduction in wastewater treatment plants. In this study, a municipal wastewater treatment plant in Northeast China was selected as the research object, and the measured data, such as air temperature, wastewater quantity, wastewater quality, and electricity consumption of the plant from 2017 to 2020 were statistically analyzed to explore the influences of temperature and wastewater quantity and wastewater quality indicators of influent and effluent on energy consumption. Firstly, the range of influent quantity in the wastewater treatment plant was large. The influent quantity in summer was high because some rainwater entered the sewage treatment plant. In winter, average daily electricity consumption (ADEC) was higher than that in summer. The relationship between ADEC and the wastewater quantity showed a positive correlation, and ADEC slowly increased with the increase in wastewater quantity. Electricity consumption per unit of wastewater (UEC) was negatively correlated with the wastewater quantity, but the correction coefficient in winter was larger than that in summer. Secondly, the ranges of chemical oxygen demand (CODCr) and ammonia nitrogen in influent were large, and the ranges of CODCr and ammonia nitrogen in effluent were small. Influent CODCr concentration was negatively correlated with influent ammonia nitrogen concentration. ADEC increased slightly with the increase in influent CODCr concentration. In winter, the increasing trend of ADEC with the influent CODCr concentration was higher than that in the summer. The increasing trend of UEC with the increase in influent COD concentration in summer was more significant than that in winter. Thirdly, influent CODCr in 11.6% of the samples exceeded the corresponding designed value, and influent ammonia nitrogen concentration in 41.4% of the samples exceeded the corresponding designed value. Effluent CODCr in 10.6% of the samples exceeded the First Level Class B standard in “Discharge Standard of Pollutants for Municipal Wastewater Treatment Plants (GB18918-2002)”, and unqualified CODCr in 94% of the effluent samples was ascribed to the unqualified ammonia nitrogen concentration in the influent samples. The electricity consumption level under abnormal conditions was higher than that under normal conditions. Fourthly, ADEC was positively correlated with the average daily CODCr reduction. The correction coefficient of ADEC with average daily CODCr reduction was greater in winter than that in summer. Fifthly, the average electricity consumption per unit of wastewater was close to the national average energy consumption, displaying the characteristics of high energy consumption in winter and low energy consumption in summer. The correlation analysis results of unit electricity consumption and temperature showed that when it was below 0 °C, the lower the temperature, the higher the electricity consumption. In Northeast China, the influences of seasons and temperatures on the electricity consumption of sewage plants were obvious. Accordingly, it is necessary to implement the diversion of rainwater and sewage, reduce the discharge of unqualified wastewater from enterprises, and take thermal insulation measures in winter. In addition, activated sludge microorganisms suitable for a low temperature area and the optimal scheduling of sewage pipe networks can also improve the operation and management of sewage treatment plants.

Extensive urbanization around the world has caused a great loss of farmland, which significantly impacts the ecosystem services provided by farmland. This study investigated the farmland loss due to urbanization in the Guangdong–Hong Kong–Macao Greater Bay Area (GBA) of China from 1980 to 2018 based on multiperiod datasets from the Land Use and Land Cover of China databases. Then, we calculated ecosystem service values (ESVs) of farmland using valuation methods to estimate the ecosystem service variations caused by urbanization in the study area. The results showed that 3711.3 km2 of farmland disappeared because of urbanization, and paddy fields suffered much higher losses than dry farmland. Most of the farmland was converted to urban residential land from 1980 to 2018. In the past 38 years, the ESV of farmland decreased by 5036.7 million yuan due to urbanization, with the highest loss of 2177.5 million yuan from 2000–2010. The hydrological regulation, food production and gas regulation of farmland decreased the most due to urbanization. The top five cities that had the largest total ESV loss of farmland caused by urbanization were Guangzhou, Dongguan, Foshan, Shenzhen and Huizhou. This study revealed that urbanization has increasingly become the dominant reason for farmland loss in the GBA. Our study suggests that governments should increase the construction of ecological cities and attractive countryside to protect farmland and improve the regional ESV.

Unprecedented urbanization has occurred globally, which has converted substantial natural landscapes into impervious surfaces and further impacted ecosystem services and functioning. In this study, we quantified the spatiotemporal patterns of urbanization and investigated the impacts of urbanization on the ecosystem service value (ESV) in the Guangdong-Hong Kong-Macao Greater Bay Area (GBA) of China from 1980 to 2018. The results show that the GBA has experienced extensive urbanization, with the urban area increasing from 2607.4 to 8243.5 km2 from 1980 to 2018. Zhongshan, Zhuhai, Dongguan, Shenzhen, and Foshan exhibited the top five highest urban expansion rates. Throughout the study period, edge expansion was the most dominant growth mode, with a decreasing trend, while infilling increased in the GBA. The total ESV loss induced by urban expansion in the GBA reached 40.5 billion yuan over the past four decades. The ESV loss due to the water body decrease caused by urbanization was the largest. Our study suggests that decision-makers should control new urban areas and protect water bodies, wetlands, and forests with high ESVs to promote the sustainable development of urban agglomerations.

Cholesterol metabolism is tightly associated with colorectal cancer (CRC). Nevertheless, the clinical benefit of statins, the inhibitor of cholesterol biogenesis mevalonate (MVA) pathway, is inconclusive, possibly because of a lack of patient stratification criteria. Here, we describe that YAP-mediated zinc finger MYND-type containing 8 (ZMYND8) expression sensitizes intestinal tumors to the inhibition of the MVA pathway. We show that the oncogenic activity of YAP relies largely on ZMYND8 to enhance intracellular de novo cholesterol biogenesis. Disruption of the ZMYND8-dependent MVA pathway greatly restricts the self-renewal capacity of Lgr5+ intestinal stem cells (ISCs) and intestinal tumorigenesis. Mechanistically, ZMYND8 and SREBP2 drive the enhancer-promoter interaction to facilitate the recruitment of Mediator complex, thus upregulating MVA pathway genes. Together, our results establish that the epigenetic reader ZMYND8 endows YAP-high intestinal cancer with metabolic vulnerability.

Coral reef islands provide precious living space and valuable ecological services for human beings, and its sustainability cannot be ignored under the pressure of human activities. Carrying capacity (CC) assessment has gradually become an important means to measure sustainability of islands. However, there is little comprehensive evaluation of the carrying capacity of coral reef islands, and traditional evaluation methods are difficult to express the social-ecological characteristics of coral reef islands. The present paper proposes a comprehensive assessment model for coral reef island carrying capacity (CORE-CC) which comprises dimensions of resources supply, environmental assimilative, ecosystem services, and socio-economic supporting. According to the characteristics of the coral reef islands, the core factors and indicators of each dimension are selected and the corresponding assessment index system of "pressure-support" is constructed. The assessment involves (1) identification of carrying dimensions and core factors, (2) pressure/support measurement and (3) assessment of carrying state. A case study is conducted in Zhaoshu Island of China, demonstrating the applicability of CORE-CC model and serving as a reference for adaptive management.

To determine the association between cord blood 25-hydroxyvitamin D (25(OH)D) concentration with growth, adiposity and neurodevelopment during infancy. Serum 25(OH)D was measured in cord blood by the liquid chromatography tandem mass spectrometry (LC-MS/MS) from the Shanghai’s “Allergy and Obesity Cohort study” (n = 1244). Weight, length, head circumference, and body mass index (BMI) z-scores for age were calculated based on World Health Organization Standard (at 6 months, 1 years, and 2 years). Neurodevelopment was measured at 2 years using Ages and Stages Questionnaire. Generalized estimating equation and multivariable logistic regression model were exploited to examine associations between fetal 25(OH)D concentration and offspring outcomes. The median of the 25(OH)D concentration in cord blood was 22.4 ng/ml (interquartile range, 27.3–8.6). Infants born in winter had lower 25(OH)D concentration. 25(OH)D deficiency was not associated with weight z-score (mean difference, 0.07; 95% confidence internal (CI), −0.09 to 0.23), length z-score (mean difference, 0.01; 95% CI, −0.19 to 0.21), head circumference z-score (mean difference, −0.06; 95% CI, −0.27 to 0.15) and BMI z-score (mean difference, 0.09; 95% CI, −0.07 to 0.25) or neurodevelopment during infancy, adjusting for sex, socio-economic position, pre-pregnancy maternal BMI, and maternal and neonatal characteristics. The associations did not vary by gender. A sensitivity analysis of available case analysis showed virtually the same results. Fetal vitamin D concentration was not associated with growth, adiposity or neurodevelopment during infancy. The role of vitamin D concentration and its mechanistic pathway in the early origins of adiposity needs to be clarified.

With dramatic coastline changes, developed coastal areas in China are seldom detected and compared in detail regarding the spatiotemporal evolution of coastline migration and coastal reclamation. This study detected and compared the spatiotemporal changes in coastline and coastal reclamation in three developed coastal areas: the Bohai Bay-Yellow River Estuary Zone (BHB-YREZ), the Yangtze River Estuary-Hangzhou Bay Zone (YRE-HZBZ) and the Pearl River Estuary Zone (PREZ). Landsat images from 1980, 1990, 2000, 2010 and 2018 were employed to derive the coastline and reclamation information for the three coastal areas. The ecological risk index was applied to explore the ecological risk characteristics of land use change in the reclamation areas. The results showed that the length of the coastlines in the BHB-YREZ, YRE-HZBZ and PREZ increased from 717.6 km, 716.3 km, and 519.6 km in 1980 to 1252.8 km, 822.6 km and 780.9 km in 2018, with annual change rates of 14.1 km/year, 2.8 km/year and 6.9 km/year, respectively. 91.0%, 97.8%, 84.5% of the coastline in the BHB-YREZ, YRE-HZBZ and PREZ was artificial coastline by 2018, respectively. From 1980 to 2018, the total reclamation areas in the BHB-YREZ, YRE-HZBZ and PREZ were 2531.4 km2, 1145.5 km2, and 769.2 km2, respectively. After 2000, except for agricultural land and aquaculture ponds, ports, construction land and tied islands were the main reclaimed types in the BHB-YREZ, YRE-HZBZ and PREZ, respectively. The overall ecological risk in the BHB-YREZ showed an increasing tendency during the past four decades, while in the YRE-HZBZ and PREZ, it rose from 1980 to 1990 to 2000–2010, and declined in 2010–2018. Coastal reclamation activities, especially construction land or ports, should be strictly and scientifically planned to protect the coastal environment.

Colonization of Helicobacter pylori (H. pylori) induces immune and inflammatory response in gastric mucosa. Trimethylamine N-oxide (TMAO), from diet and metabolite through the action of gut microbiota, has been linked to inflammatory diseases. To investigate the effects of TMAO and H. pylori infection on gene expression in gastric epithelial cells, Human gene chip Affymetrix HTA 2.0 was used in this study. 1312 genes were identified as differentially expressed genes in GES-1 cells with H. pylori and TMAO co-treatment compared to the control. GO and KEGG analyses indicated that the functions of these differentially expressed genes were related closely with immune inflammation. GO-network showed that Toll-like receptor signaling pathway was the most important biological processes and 49 up-regulated genes related to immune inflammation were obtained. The synergistic effects of H. pylori and TMAO enhanced the genes expression of IL-6, CXCL1, CXCL2, FOS and C3 related to immune inflammation in comparison with those of non-infected control cells, H. pylori-infected cells, and TMAO-stimulated cells. RT-PCR verified the expression levels of IL-6, CXCL1. Additionally, expression levels of 2053 genes were altered and 52 immunoinflammatory genes were upregulated in comparison with H. pylori-infected cells. This study suggested that TMAO altered the expression levels of immunoinflammatory genes induced by H. pylori infection, and the synergistic effects of H. pylori and TMAO provided novel insights into the development of chronic gastritis, gastric ulcer and gastric cancer.

Helicobacter pylori ( H. pylori ) is a spiral shaped gram-negative bacterium that induces immune responses in the gastric mucosa. Toll-like receptors (TLRs) play important roles in mediating inflammatory cytokines by recognition of conserved molecular patterns on bacteria. Changes in the expression of toll-like receptor (TLR) 2, TLR4 and the relative inflammatory cytokines were analyzed in normal gastric epithelial GES-1 cells following treatment with H. pylori or Escherichia coli lipopolysaccharide ( E. coli LPS) in order to investigate the contribution of TLRs in recognizing and mediating the inflammatory response to H. pylori , and study the differences in TLRs’ performance between H. pylori and E. coli . Specific inhibitors for the declines in TLR2 and TLR4 were also employed. The results showed that H. pylori infection increased TLR2 expression in GES-1 cells, but TLR4 remained unchanged regardless of H. pylori or TLR2 small interfering RNA treatment. Furthermore, the secretion of cyclooxygenase-2 (COX-2) induced by H. pylori was inhibited by declines in TLR2, but not in TLR4. In conclusion, TLR2 plays an even more important role than TLR4 not only in recognizing H. pylori , but also in the induction of inflammatory cytokines initiated by H. pylori . However, both TLR2 and TLR4 are necessary in mediating the inflammatory response to E. coli LPS.

Titanium dioxide nanoparticles (TiO2 NPs) are an emerging environmental concern, considering their proven toxicity and wide commercial application nowadays. Once entering natural water bodies, they...

The coastal zone is one of the most valuable ecosystems worldwide because of the diverse and significant ecosystem services (ESs) it provides for human survival and development. Changes in land-use including coastal reclamation and erosion have altered the distribution of coastline and caused substantial changes in the structure and value of coastal ESs. In the past four decades, the mainland coastline in China has undergone extensive changes primarily due to coastal reclamation. This study investigated changes in land-use and spatiotemporal variations in ESs in response to coastline movements in China over the last four decades. The results indicate that land area increased by 1.10 million ha in response to coastline movements in this time period, primarily due to reclamation for aquaculture pond, port, construction land and the development of tied islands. Coastline movements have decreased ecosystem service values (ESVs) by $6.83 billion over the past four decades. Additionally, coastline movements have affected the ESV structure, decreasing the ESVs of erosion prevention and waste treatment functions while increasing the ESV functions of gas regulation and moderation of disturbance. Greater attentions should be paid to the protection and restoration of natural coastal land in China. By assessing the loss of ESVs quantitatively in response to coastline movements, this study provides some suggestions for ecosystem-based management of coastal land in China.

The level of SETD2-mediated H3K36me3 is inversely correlated with that of EZH2-catalyzed H3K27me3. Nevertheless, it remains unclear whether these two enzymatic activities are molecularly intertwined. Here, we report that SETD2 delays prostate cancer (PCa) metastasis via its substrate EZH2. We show that SETD2 methylates EZH2 which promotes EZH2 degradation. SETD2 deficiency induces a Polycomb-repressive chromatin state that enables cells to acquire metastatic traits. Conversely, mice harboring nonmethylated EZH2 mutant or SETD2 mutant defective in binding to EZH2 develop metastatic PCa. Furthermore, we identify that metformin-stimulated AMPK signaling converges at FOXO3 to stimulate SETD2 expression. Together, our results demonstrate that the SETD2-EZH2 axis integrates metabolic and epigenetic signaling to restrict PCa metastasis.

Loss of phosphatase and tensin homolog (PTEN) represents one hallmark of prostate cancer (PCa). However, restoration of PTEN or inhibition of the activated PI3K/AKT pathway has shown limited success, prompting us to identify obligate targets for disease intervention. We hypothesized that PTEN loss might expose cells to unique epigenetic vulnerabilities. Here, we identified a synthetic lethal relationship between PTEN and Brahma-related gene 1 (BRG1), an ATPase subunit of the SWI/SNF chromatin remodeling complex. Higher BRG1 expression in tumors with low PTEN expression was associated with a worse clinical outcome. Genetically engineered mice (GEMs) and organoid assays confirmed that ablation of PTEN sensitized the cells to BRG1 depletion. Mechanistically, PTEN loss stabilized BRG1 protein through the inhibition of the AKT/GSK3β/FBXW7 axis. Increased BRG1 expression in PTEN-deficient PCa cells led to chromatin remodeling into configurations that drove a protumorigenic transcriptome, causing cells to become further addicted to BRG1. Furthermore, we showed in preclinical models that BRG1 antagonist selectively inhibited the progression of PTEN-deficient prostate tumors. Together, our results highlight the synthetic lethal relationship between PTEN and BRG1 and support targeting BRG1 as an effective approach to the treatment of PTEN-deficient PCa.

Environmental carrying capacity (ECC) provides an insight into measuring sustainability of the vulnerable coral reef islands. However, an integrated assessment of ECC on the social-ecological system of reef islands is rarely existence. And conventional approaches miss addressing the difference of social development, which would lead to a misinterpretation of sustainable development of reef island system. This study develops an evolving model of RI-ECC which incorporates five specific development phases, and the assessment involves (1) identification and measurement of carrying components, (2) supply/demand surplus analysis of indicators and (3) ECC states determination. A case study is conducted in Zhaoshu Island of China, indicating the efficiency of RI-ECC model and serving as a reference for adaptive management.

Aurora kinase B, playing a vital, important role in mitosis, is frequently detected to be overexpressed in many cancer cell lines and various tumor tissues, including prostatic carcinoma. Given the essential function of Aurora kinase B in mitosis and its association with tumorigenesis, it might be a drug target for prostatic carcinoma treatment. In our study, short hairpin RNA targeting Aurora kinase B was cloned into a pGPU6 plasmid vector and then transfected into human prostatic carcinoma cells. The expression level of Aurora kinase B was verified by reverse transcription-polymerase chain reaction and Western blot. At the same time, cell apoptosis was detected by 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2H-tetrazolium bromide, fluorescent staining, and flow cytometric analysis. Furthermore, prostate carcinoma cells were injected into mice to establish a tumor xenograft model. Previous studies have shown the effect of pGPU6-shAURKB plasmid on tumor growth in a prostate carcinoma xenogenic implantation model. From the study, we knew that the Aurora kinase B was significantly downregulated in prostate carcinoma cells, and cell apoptosis was also detected higher in treated groups than that in control groups. Moreover, in the prostate carcinoma xenogenic implantation model, compared with the control groups, the tumor growth was inhibited about 78.7% in the pGPU6-shAURKB plasmid–treated group, and cell apoptosis in the experimental group was notably higher than that in control groups. The average duration of tumor-bearing mice was prolonged to about 35 days. The results of experiment indicated that specific knockdown of Aurora kinase B led to prostate carcinoma cells apoptosis and inhibited tumor growth. Our data clearly confirmed that specific knockdown of Aurora kinase B expression by vector-based short hairpin RNA/liposome may be a potential new approach to treat human prostatic carcinoma.

According to the landform location, lithology and lithofacies features, special interlayer, geological age and pollen analysis of sediment distribution, this paper ensured the deposition sequence and formation age of Quaternary deposition in Yanji basin, and explored the evaluation progress of the regional paleogeography environment. Results showed that: (1) After analyzing the shear wave velocity and section of both HDBZK-2 and HDBZK-3 respectively, it was found that vse of Cretaceous was far bigger than vse of Quaternary; (2) The Quaternary section of Yanji basin was divided into two segments. Holocene deposit (0-4m): it was typical river sediment. Late Pleistocene deposit (4-13.5m): it was typical river sediment, which was equivalent to the sediments in the last glaciation; (3) According to field geological investigation, the late period of Holocene deposit was mainly distributed in floodplain and riverbed, and the lithology was mainly gravel, sand and clay. The middle Pleistocene deposit was mainly distributed at the third terrace of Buerhatong River and its branches. The bottom was gravel layer and the top was sand and clay layer; (4) Since the late period of the late Pleistocene, the regional climate has experienced a cycle of relatively cold, dry cold, relatively cold, dry cold, relatively cold and wet humid.According to the landform location, lithology and lithofacies features, special interlayer, geological age and pollen analysis of sediment distribution, this paper ensured the deposition sequence and formation age of Quaternary deposition in Yanji basin, and explored the evaluation progress of the regional paleogeography environment. Results showed that: (1) After analyzing the shear wave velocity and section of both HDBZK-2 and HDBZK-3 respectively, it was found that vse of Cretaceous was far bigger than vse of Quaternary; (2) The Quaternary section of Yanji basin was divided into two segments. Holocene deposit (0-4m): it was typical river sediment. Late Pleistocene deposit (4-13.5m): it was typical river sediment, which was equivalent to the sediments in the last glaciation; (3) According to field geological investigation, the late period of Holocene deposit was mainly distributed in floodplain and riverbed, and the lithology was mainly gravel, sand and clay. The middle Pleistocene deposit was mainly di...

The aim of this study was to explore the antibacterial activity of Pyrrosia petiolosa ethyl acetate extract (PPEAE) against Staphylococcus aureus in vitro and analyse its chemical components by gas chromatograph-mass spectrometry. The results of anti-microbial assay revealed that PPEAE had strong inhibitory activity against S .aureus, with MIC and MBC of 7.8 and 15.6 mg/mL, respectively. The transcriptional levels of hla and sea were reduced to 14.33 and 46.39% at the MIC compared to the control. Analysing test result exhibited that eugenol made a great contribution to antibacterial activity. This experiment indicated that PPEAE had prominent antibacterial activity against S. aureus.

chinese acad sci, inst semicond, state key lab superlattices & microstruct, beijing 100083, peoples r china; chinese acad sci, inst phys, state key lab surface phys, beijing 100080, peoples r china

Rapid thermal annealing (RTA), with fast ramp rate, was performed on several Cu(In,Ga)Se2 (CIGS) films and solar cells under various peak annealing temperatures and holding times. Characterizations were made on CIGS films and cells before and after RTA treatments to study effects of RTA on the CIGS film properties and cell performance. In addition, AMPS-1D device simulation program was used to study effects of defect density on the cell performance by fitting the experimental data of RTA-treated CIGS cells. The results show that RTA treatments under optimal annealing condition can provide significant improvements in the electrical properties of CIGS films and cell performance while preserving the film composition and microstructure morphology. r 2006 Elsevier B.V. All rights reserved.

Pulsed non-melt laser annealing (NLA) has been used for the first time to modify near-surface defects and related junction properties in Cu(In,Ga)Se2 (CIGS) solar cells. CIGS films deposited on Mo/glass substrates were annealed using a 25 ns pulsed 248 nm laser beam at selected laser energy density in the range 20–60 mJ/cm2 and pulse number in the range 5–20 pulses. XRD peak narrowing and SEM surface feature size increase suggest near-surface structure changes. Dual-beam optical modulation (DBOM) and Hall-effect measurements indicate NLA treatment increases the effective carrier lifetime and mobility along with the sheet resistance. In addition, several annealed CdS/CIGS films processed by NLA were fabricated into solar cells and characterized by photo- and dark-J–V and quantum efficiency (QE) measurements. The results show significant improvement in the overall cell performance when compared to unannealed cells. The results suggest that an optimal NLA energy density and pulse number for a 25 ns pulse width are approximately 30 mJ/cm2 and 5 pulses, respectively. The NLA results reveal that overall cell efficiency of a cell processed from an unannealed film increased from 7.69% to 13.41% and 12.22% after annealing 2 different samples at the best condition prior to device processing.

We report the results of an extensive study employing numerous methods to characterize carrier transport within copper indium gallium sulfoselenide (CIGSS) photovoltaic devices, whose absorber layers were fabricated by diverse process methods in multiple laboratories. This collection of samples exhibits a wide variation of morphologies, compositions, and solar power conversion efficiencies. An extensive characterization of transport properties is reported here—including those derived from capacitance–voltage, admittance spectroscopy, deep level transient spectroscopy, time-resolved photoluminescence, Auger emission profiling, Hall effect, and drive level capacitance profiling. Data from each technique were examined for correlation with device performance, and those providing indicators of related properties were compared to determine which techniques and interpretations provide credible values for transport properties. Although these transport properties are not sufficient to predict all aspects of current-voltage characteristics, we have identified specific physical and transport characterization methods that can be combined using a model-based analysis algorithm to provide a quantitative prediction of voltage loss within the absorber. The approach has potential as a tool to optimize and understand device performance irrespective of the specific process used to fabricate the CIGSS absorber layer. Copyright © 2005 John Wiley & Sons, Ltd.

Indium tin oxide films grown by conventional and ultraviolet-assisted pulsed laser deposition technique (PLD and UVPLD) on Si and Corning glass were analyzed by grazing and symmetric incidence X-ray diffraction. Films deposited at substrate temperatures up to 70 °C were amorphous, while films deposited at temperatures of 120 °C and higher showed good crystallinity, with a (2 2 2) texture. The diffraction peaks were split indicating that the films contained a two-layer structure. X-ray reflectivity studies showed that the film surface roughness was below 0.5 nm and their density approximately 7.20 g/cm 3 . Spectroscopic ellipsometry measurements indicated that the films were highly transparent, while X-ray photoelectron spectroscopy investigations showed homogeneous bulk chemical composition and a very small Sn enrichment in the surface region. The carrier mobility was rather high for films deposited at 40 and 70 °C and then decreased with the increase of the substrate temperature, because the onset of crystallization at such low temperatures produces a defective structure.

The effects of post annealing treatment were investigated on the CdS sensitized ZnO and TiO 2 nanocrystalline solar cells. It was found that the annealing will increase the cell efficiency on ZnO and TiO 2 with porous structures. A significant increase of cell efficiency from 0.54% to 1.07% was observed for CdS sensitized porous ZnO solar cells after annealing and 0.52% to 1.29% for CdS sensitized electrospun porous TiO 2 electrode. The increase is attributed to the film morphology improvement and the absorption band edge shift of CdS. The annealing does not increase the efficiency for solar cells made from CdS sensitized TiO 2 without porous structure.

Land use change has become a new field in global change research, and it is closely related to land resource security and sustainable development. The environmental simulation model was mostly used to study the land-use change before. In this paper, we use the Economic Lorenz curve and Gini coefficient of economic model to study the land use structure changes in the western plain of Jilin Province, China. The results showed that the Lorenz curve has the phenomenon of “two near and two far” and Gini coefficient “two increased and two decreased”. That is to say, during the 15 years from 1989 to 2004, the areas of cultivated land and unused land had increased, Lorenz curves were near to the perfect equality line, and the distribution tended to be uniform; the areas of grassland and water body were reduced, the Lorenz curves were away from the perfect equality line, and the distribution tended to be increasingly uneven, which reflects the main process of the land use structure changes. Studying on the land use changes based on Economic model is simpler and more intuitionistic, and had the generalization values.

Studies of the effect of pulsed laser annealing (PLA) and rapid thermal annealing (RTA) on Cu(In,Ga)Se/sub 2/ (CIGS) films and devices under various annealing conditions are reported in this paper. Several characterizations were carried out before and after each annealing. The results show that both of these two techniques could positively benefit the CIGS film properties and device performance.

Rapid thermal annealing (RTA), with fast ramp up and down rates, was performed on several Cu(In,Ga)Se2 (CIGS) films and solar cells under various peak annealing temperatures and holding times. The XRD, SEM, Hall- effect, photo J-V, and quantum efficiency (Q-E) measurements were made on CIGS films and cells before and after RTA treatments to study the effects of RTA on the CIGS film properties and cell performance. The results show that RTA treatments under optimal annealing condition can provide significant improvements in the electrical properties (resistivity, carrier concentration, and mobility) of CIGS films and cell performance while preserving the film composition and microstructure morphology.