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Abstract To enable open environment application of artificial photosynthesis, the direct utilization of environmental CO2 via an oxygen-tolerant reductive procedure is necessary. Herein, we introduce an in situ growth strategy for fabricating two-dimensional heterojunctions between indium porphyrin metal-organic framework (In-MOF) and single-layer graphene oxide (GO). Upon illumination, the In-MOF/GO heterostructure facilitates a tandem CO2 capture and photocatalytic reduction on its hydroxylated In-node, prioritizing the reduction of dilute CO2 even in the presence of air-level O2. The In-MOF/GO heterostructure photocatalyst is integrated with a porous polytetrafluoroethylene (PTFE) membrane to construct a floatable artificial leaf. Through a triphase photocatalytic reaction, the floatable artificial leaf can remove aqueous contaminants from real water while efficiently reducing CO2 at low concentrations (10%, approximately the CO2 concentration in combustion flue gases) upon air-level O2. This study provides a scalable approach for the construction of photocatalytic devices for CO2 conversion in open environments.

Abstract Introduction Tibetan sheep, economically important animals on the Qinghai–Tibet Plateau, have diversified into numerous local breeds with unique characteristics through prolonged environmental adaptation and selective breeding. However, most current research focuses on one or two breeds, and lacks a comprehensive representation of the genetic diversity across multiple Tibetan sheep breeds. This study aims to fill this gap by investigating the genetic structure, diversity and high-altitude adaptation of 6 Tibetan sheep breeds using whole-genome resequencing data. Results Six Tibetan sheep breeds were investigated in this study, and whole-genome resequencing data were used to investigate their genetic structure and population diversity. The results showed that the 6 Tibetan sheep breeds exhibited distinct separation in the phylogenetic tree; however, the levels of differentiation among the breeds were minimal, with extensive gene flow observed. Population structure analysis broadly categorized the 6 breeds into 3 distinct ecological types: plateau-type, valley-type and Euler-type. Analysis of unique single-nucleotide polymorphisms (SNPs) and selective sweeps between Argali and Tibetan sheep revealed that Tibetan sheep domestication was associated primarily with sensory and signal transduction, nutrient absorption and metabolism, and growth and reproductive characteristics. Finally, comprehensive analysis of selective sweep and transcriptome data suggested that Tibetan sheep breeds inhabiting different altitudes on the Qinghai–Tibet Plateau adapt by enhancing cardiopulmonary function, regulating body fluid balance through renal reabsorption, and modifying nutrient digestion and absorption pathways. Conclusion In this study, we investigated the genetic diversity and population structure of 6 Tibetan sheep breeds in Qinghai Province, China. Additionally, we analyzed the domestication traits and investigated the unique adaptation mechanisms residing varying altitudes in the plateau region of Tibetan sheep. This study provides valuable insights into the evolutionary processes of Tibetan sheep in extreme environments. These findings will also contribute to the preservation of genetic diversity and offer a foundation for Tibetan sheep diversity preservation and plateau animal environmental adaptation mechanisms.

Abstract Solar-driven flat-panel H2O-to-H2 conversion is an important technology for value-added solar fuel production. However, most frequently used particulate photocatalysts are hard to achieve stable photocatalysis in flat-panel reaction module due to the influence of mechanical shear force. Herein, a highly active CdS@SiO2-Pt composite with rapid CdS-to-Pt electron transfer and restrained photoexciton recombination was prepared to process into an organic-inorganic membrane by compounding with polyvinylidene fluoride (PVDF). This PVDF networked organic-inorganic membrane displays high photostability and excellent operability, achieving improved simulated sunlight-driven alkaline H2O-to-H2 conversion activity (213.48 mmol m−2 h−1) following a 0.68% of solar-to-hydrogen efficiency. No obvious variation in its appearance and micromorphology was observed even being recycled for 50-times, which considerably outperforms the existing membrane photocatalysts. Subsequently, a homemade panel H2O-to-H2 conversion system was fabricated to obtain a 0.05% of solar-to-hydrogen efficiency. In this study, we opens up a prospect for practical application of photocatalysis technology.

Abstract The creation of well-defined hollow two-dimensional structures from small organic molecules, particularly those with controlled widths and numbers of segments, remains a formidable challenge. Here we report the fabrication of the well-defined concentric hollow two-dimensional platelets with programmable widths and numbers of segments through constructing a concentric multiblock two-dimensional precursor followed by post-processing. The fabrication of concentric multi-hexagons two-dimensional platelets is realized by the alternative heteroepitaxial growth of two donor-acceptor molecules. Upon ultraviolet irradiation, one of the two donor-acceptor molecules can be selectively oxidized by singlet oxygen generated during the process, and the oxidized product becomes more soluble due to increased polarity. This allows for selective removal of the oxidized segments simply by solvent dissolution, yielding hollow multiblock two-dimensional structures. The hollow two-dimensional platelets can be utilized as templates to lithograph complex electrodes with precisely controlled gap sizes, thereby offering a platform for examining the optoelectronic performance of functional materials.

Abstract Background Elucidating the genetic variation underlying phenotypic diversity will facilitate improving production performance in livestock species. The Tibetan sheep breed in China holds significant historical importance, serving as a fundamental pillar of Qinghai’s animal husbandry sector. The Plateau-type Tibetan sheep, comprising 90% of the province’s population, are characterized by their tall stature and serve as the primary breed among Tibetan sheep. In contrast, Zhashijia sheep exhibit larger size and superior meat quality. These two species provide an excellent model for elucidating the genetic basis of body size variation. Therefore, this study aims to conduct a comprehensive genome-wide association study on these two Tibetan sheep breeds to identify single nucleotide polymorphism loci and regulatory genes that influence body size traits in Tibetan sheep. Result In this study, the phenotypic traits of body weight, body length, body height, chest circumference, chest depth, chest width, waist angle width, and pipe circumference were evaluated in two Tibetan sheep breeds: Plateau-type sheep and Zhashijia Tibetan sheep. Whole genome sequencing generated 48,215,130 high-quality SNPs for genome-wide association study. Four methods were applied and identified 623 SNPs significantly associated with body size traits. The significantly associated single nucleotide polymorphisms identified in this study are located near or within 111 candidate genes. These genes exhibit enrichment in the cAMP and Rap1 signaling pathways, significantly affecting animal growth, and body size. Specifically, the following genes were associated: ASAP1, CDK6, FRYL, NAV2, PTPRM, GPC6, PTPRG, KANK1, NTRK2 and ADCY8. Conclusion By genome-wide association study, we identified 16 SNPs and 10 candidate genes associated with body size traits in Tibetan sheep, which hold potential for application in genomic selection breeding programs in sheep. Identifying these candidate genes will establish a solid foundation for applying molecular marker-assisted selection in sheep breeding and improve our understanding of body size control in farmed animals.

Abstract Semiconductor‐based photoelectrochemical (PEC) organic transformations usually show radical characteristics, in which the reaction selectivity is often difficult to precisely control due to the nonselectivity of radicals. Accordingly, several simple organic reactions (e.g., oxidations of alcohols, aldehydes, and other small molecules) have been widely studied, while more complicated processes like C─C coupling remain challenging. Herein, a synergistic heterogeneous/homogeneous PEC strategy is developed to achieve a controllable radical‐induced C─C coupling reaction mediated by the copper‐coordination effect at the semiconductor/electrolyte interfaces, which additionally exerts a significant impact on the product regioselectivity. Through experimental studies and theoretical simulations, this study reveals that the copper‐chloride complex effectively regulates the formation of chloride radicals, a typical hydrogen atom transfer agent, on semiconductor surfaces and stabilizes the heterogeneous interfaces by suppressing the radical‐induced surface passivation. Taking the Minisci reaction (the coupling between 2‐phenylquinoline and cyclohexane) as a model, the yield of the target C─C coupling product reaches up to 90% on TiO2 photoanodes with a selectivity of 95% and long‐term stability over 100 h. Moreover, such a strategy exhibits a broad scope and can be used for the functionalization of various heteroaromatic hydrocarbons.

Abstract Direct solar-to-hydrogen conversion from pure water using all-organic heterogeneous catalysts remains elusive. The challenges are twofold: (i) full-band low-frequent photons in the solar spectrum cannot be harnessed into a unified S 1 excited state for water-splitting based on the common Kasha-allowed S 0 → S 1 excitation; (ii) the H+ → H2 evolution suffers the high overpotential on pristine organic surfaces. Here, we report an organic molecular crystal nanobelt through the self-assembly of spin-one open-shell perylene diimide diradical anions (:PDI2-) and their tautomeric spin-zero closed-shell quinoid isomers (PDI2-). The self-assembled :PDI2-/PDI2- crystal nanobelt alters the spin-dependent excitation evolution, leading to spin-allowed S 0 S 1 → 1 (TT) → T 1 + T 1 singlet fission under visible-light (420 nm~700 nm) and a spin-forbidden S 0 → T 1 transition under near-infrared (700 nm~1100 nm) within spin-hybrid chromophores. With a triplet-triplet annihilation upconversion, a newly formed S 1 excited state on the diradical-quinoid hybrid induces the H+ reduction through a favorable hydrophilic diradical-mediated electron transfer, which enables simultaneous H2 and O2 production from pure water with an average apparent quantum yield over 1.5% under the visible to near-infrared solar spectrum.

Alkene epoxidation, whose products are important intermediates for the manufacture of pharmaceuticals and epoxy resins, has attracted extensive attention. Unlike the conventional electrochemical Br−/Br2-mediated epoxidation, here the authors report a photoelectrochemical Br−/BrO−- mediated system to achieve efficient epoxidation performance on α-Fe2O3.

Clarifying the influencing mechanism of rural revitalization on agricultural carbon emissions is crucial for attaining carbon peaking and carbon neutrality. This study utilized spatial econometric model, mediating effect model and dual fixed effect model to explore the influence and spatial impact of rural revitalization on carbon emissions from agricultural land by using the panel data of prefectural cities in Henan Province. Results indicate that rural revitalization exerts a notable beneficial influence on carbon emissions, as its improvement results in a rise in such emissions. Furthermore, rural revitalization demonstrates a favorable spatial spillover effect on agricultural carbon emissions in neighboring cities. Agricultural GDP and mechanical technological progress act as intermediate factors, as rural revitalization promotes carbon emissions from agriculture by fostering economic development and technological advancements. Heterogeneity analysis indicates that the correlation between rural revitalization and greenhouse gas emissions from agriculture is nonlinear, as moderate and low levels of rural revitalization promote agricultural carbon emissions, while higher levels exhibit a negative effect. Thus, rural revitalization exhibits an inflection point effect on agricultural carbon emissions.

While plasmonic metals show some activity for photocatalysis, they often must be paired with semiconductors or sacrificial reagents. Here, authors find quantum-sized Au nanoparticles can achieve photocatalytic CO2-to-CO conversion with H2O by charge carriers generated from interband transitions.

Using a single catalyst to mimic the two-step photosynthesis for CO2 conversion remains a challenge. Here, the authors report a simple Bi catalyst that can act as an electron-proton-transfer mediator to spatially and temporally separate H2O splitting and CO2 reduction reactions in CO2-to-CO conversion process.

Abstract The design of sensor array members with synchronous fluorescence and photostability is crucial to the reliable performance of sensor arrays in multiple detections and their service life. Herein, a strategy is reported for achieving synchronous fluorescence and photostability on two coassemblies fabricated from carbazole‐based energy donor hosts and a photostable energy acceptor. When a small number of the same energy acceptors are embedded into two carbazole‐based energy donor hosts, the excitation energy of the donors can be efficiently harvested by the acceptors through long‐range exciton migration and Förster resonance energy transfer (FRET) to achieve synchronous fluorescence and photostability in both coassemblies. More intriguingly, the synchronous photostability substantially improves the multiple discrimination capacity (e.g., 10 times more discriminations of TNT in two coassemblies have been achieved compared to the sensor array comprising two individual donor assemblies) and the working lifetime of the sensor array. The concept of optical synchronization (i.e., emission and photostability) of sensor array members can be extended to other sensor arrays for the steady multiple detection of certain hazardous chemicals.

Urban residential carbon dioxide (CO2) emissions have increased sharply along with the rapid urbanization process. Few studies have considered the different effects of influencing factors between Northern and Southern China, and the analysis of CO2 per unit area from the spatial perspective is also rarely involved. Using the spatial Durbin model (SDM), this study aimed at revealing the influencing factors (including income, inequality, population density, urban morphology, etc.) on CO2 per capita and CO2 per unit area during 2001–2018 between Northern and Southern China. The results showed that the Northern cities had higher carbon emissions and a faster growth rate, and the high-high clusters were also mainly located in the Northern cities. The Gini coefficient was correlated adversely with CO2, while income imposed a positive effect on carbon emissions. The negative coefficients of the quadratic term of the GDP per capita demonstrated that the residential carbon emissions have the potential to decrease when the income increases to a certain level. The indirect effects of income and the Gini showed that spatial spillover effects exist. Urban population density and the ratio of residential area to built-up area had an opposite effect on CO2 per capita and CO2 per unit area, and they have a bigger impact on the CO2 per unit area. This study revealed the different roles of various factors in reducing CO2 per unit area from the spatial perspective and CO2 per capita from the non-spatial perspective between the Northern and Southern regions, which could help policymakers to design targeted mitigation measures in the residential sector in China, providing references for developing countries to jointly reduce carbon emissions to promote the mitigation of global climate change.

Improving water utilization efficiency can effectively alleviate the contradiction between water shortage and water demand in the process of rapid urbanization. The middle and lower reaches of the Yellow River Basin, China, are characterized by water shortage. In order to improve water use efficiency, taking the 43 prefecture-level units in this region as the study area, industrial and agricultural water use efficiency is calculated based on the undesired SBM-DEA model. Then, the Tobit model is used to explore their influencing factors. The results show that the regional average agricultural water use efficiency is greater than the industrial water use efficiency. The temporal trend indicates that the agricultural water use efficiency shows a fluctuating upward trend, while industrial water use efficiency has a fluctuating downward trend. The gravity center of industrial water use efficiency moves from northwest to southeast in a “Z” shape, while the gravity center of agricultural water use efficiency moves westward as a whole. From the perspective of spatial patterns, the standard deviation ellipse of industrial water use efficiency shows that the industrial water use efficiency is higher in the east–west direction, while the agricultural water use efficiency is higher in the northwest–southeast direction. The improvement of urbanization level is conducive to the improvement of industrial water use efficiency; however, the development of urbanization has a significant inhibitory effect on improving agricultural water use efficiency.

Abstract Real‐time, high signal intensity, and prolonged detection is challenging because of the rarity of fluorophores with both high photostability and luminescence efficiency. In this work, new donor–acceptor (D–A) molecules for overcoming these limitations are reported. A hybridized local and an intramolecular charge‐transfer excited state is demonstrated to afford high photoluminescence efficiency of these D–A molecules in solution (≈100%). The twisted molecular structure and bulky alkyl chains effectively suppress π–π and dipole–dipole interactions, enabling high luminescence efficiency of 1 and 2 in the solid state (≈94% and 100%). Furthermore, two D–A aggregates exhibit high photostability as evidenced by 4% and 8% of the fluorescence decreasing after 6 h of continuous irradiation in air, which is in sharp contrast to ≈95% of fluorescence decreasing in a reference compound. Importantly, with these molecules, ultrasensitive detection of sulfur mustard (SM) with a record limit of 10 ppb and selective detection of SM in complex matrices are achieved.

Due to the rapid economic growth and the heavy reliance on fossil fuels, China has become one of the countries with the highest sulfur dioxide (SO2) emissions, which pose a severe challenge to human health and the sustainable development of social economy. In order to cope with the serious problem of SO2 pollution, this study attempts to explore the spatial temporal variations of industrial SO2 emissions in China utilizing the Defense Meteorological Satellite Program's Operational Linescan System (DMSP-OLS) nighttime stable light (NSL) data. We first explored the relationship between the NSL data and the statistical industrial SO2 emissions at the provincial level, and confirmed that there was a positive correlation between these two datasets. Consequently, 17 linear regression models were established based on the NSL data and the provincial statistical emissions to model the spatial-temporal dynamics of China's industrial SO2 emissions from 1997 to 2013. Next, the NSL-based estimated results were evaluated utilizing the prefectural statistical industrial SO2 emissions and emission inventory data, respectively. Finally, the distribution of China's industrial SO2 emissions at 1 km spatial resolution were estimated, and the temporal and spatial dynamics were explored from multiple scales (national scale, regional scale and scale of urban agglomeration). The results show that: (1) The NSL data can be successfully applied to estimate the dynamic changes of China's industrial SO2 emissions. The coefficient of determination (R2) values of the NSL-based estimation results in most years were greater than 0.6, and the relative error (RE) values were less than 10%, when validated by the prefectural statistical SO2 emissions. Moreover, compared with the inventory emissions, the adjusted coefficient of determination (Adj.R-Square) reached 0.61, with the significance at the 0.001 level. (2) During the observation period, the temporal and spatial dynamics of industrial SO2 emissions varied greatly in different regions. The high growth type was largely distributed in China's Western region, Central region, and Shandong Peninsula, while the no-obvious-growth type was concentrated in Western region, Beijing-Tianjin-Tangshan and Middle south of Liaoning. The high grade of industrial SO2 emissions was mostly concentrated in China's Eastern region, Western region, Shanghai-Nanjing-Hangzhou and Shandong Peninsula, while the low grade mainly concentrated in China's Western region, Middle south of Liaoning and Beijing-Tianjin-Tangshan. These results of our research can not only enhance the understanding of the spatial-temporal dynamics of industrial SO2 emissions in China, but also offer some scientific references for formulating feasible industrial SO2 emission reduction policies.

Water resources are indispensable for all social-economic activities and ecosystem functions. In addition, changes in water resources have great significance for agricultural production. This paper uses five global climate models from CMIP5 to evaluate the future spatiotemporal variation in water resources in China under four RCP scenarios. The results show that the available precipitation significantly decreases due to evapotranspiration. Comparing the four RCP scenarios, the national average of the available precipitation is the highest under the RCP 2.6 and 4.5 scenarios, followed by that under the RCP 8.5 scenario. In terms of spatial distribution, the amount of available precipitation shows a decreasing trend from southeast to northwest. Regarding temporal changes, the available precipitation under RCP 8.5 exhibits a trend of first increasing and then decreasing, while the available precipitation under the RCP 6.0 scenario exhibits a trend of first decreasing and then increasing. Under the RCP 2.6 and 4.5 scenarios, the available precipitation increases, and the RCP 4.5 scenario has a higher rate of increase than that of RCP 2.6. In the context of climate change, changes in water resources and temperature cause widespread increases in potential agricultural productivity around Hu's line, especially in southwestern China. However, the potential agricultural productivity decreases in a large area of southeastern China. Hu's line has a partial breakthrough in the locking of agriculture, mainly in eastern Tibet, western Sichuan, northern Yunnan and northwestern Inner Mongolia. The results provide a reference for the management and deployment of future water resources and can aid in agricultural production in China.

During the last several decades TiO2 photocatalytic oxidation using the molecular oxygen in air has emerged as a promising method for the degradation of recalcitrant organic pollutants and selective transformations of valuable organic chemicals. Despite extensive studies, the mechanisms of these photocatalytic reactions are still poorly understood due to their complexity. In this review, we will highlight how the oxygen-18 isotope labeling technique can be a powerful tool to elucidate complicated photocatalytic mechanisms taking place on the TiO2 surface. To this end, the application of the oxygen-18 isotopic-labeling method to three representative photocatalytic reactions is discussed: (1) the photocatalytic hydroxylation of aromatics; (2) oxidative cleavage of aryl rings on the TiO2 surface; and (3) photocatalytic decarboxylation of saturated carboxylic acids. The results show that the oxygen atoms of molecular oxygen can incorporate into the corresponding products in aqueous solution in all three of these reactions, but the detailed incorporation pathways are completely different in each case. For the hydroxylation process, the O atom in O2 is shown to be incorporated through activation of O2 by conduction band electrons. In the cleavage of aryl rings, O atoms are inserted into the aryl ring through the site-dependent coordination of reactants on the TiO2 surface. A new pathway for the decarboxylation of saturated carboxylic acids with pyruvic acid as an intermediate is identified, and the O2 is incorporated into the products through the further oxidation of pyruvic acid by active species from the activation of O2 by conduction band electrons.

The photocatalytic degradation of Rhodamine B (RhB) with TiO2 and TiO2/SiO2 in the aqueous dispersion was investigated under both the visible light (λ> 480 nm) and UV irradiation. The detailed photocatalytic oxidative process of RhB under these different conditions was revealed by measurement of the isoelectric points of the catalysts, UV-VIS spectra, HPLC and LC-MS. RhB adsorbs on the surface of TiO2/SiO2 particles by the positively-charged diethylamino group while, in the case of net TiO2, it adsorbs through the negatively-charged carboxyl group under the experimental conditions (pH ∼ 4.3). In the RhB-TiO2/SiO2 system, RhB firstly underwent a highly selective stepwise deethylation process before the destruction of the chromophore structure under visible light irradiation. The average yield of the every deethylation step was higher than 86%. It is confirmed that visible light-induced photocatalytic degradation of dye proceeds on the surface of catalysts rather than in the bulk solution and active oxygen species preferentially attack the molecular portion that connects directly to the surface of catalysts. This work provides a possibility for the modification of the surface characteristics of TiO2 to adsorb effectively the special colored organic molecules in selective mode for selective modification or deeply extent photooxidation.

We analyzed the spatial and temporal distributions of temperature and precipitation in China’s Yellow River Region between 1960 and 2001 by compiling meteorological data using anomalies, climate trend rate, linear regression, trend analysis, spline functions, and other methods. The results show that the average temperatures in the Region have an upward trend at a rate of 0.19°C every 10 years. There are no significant changes in the Region’s summers, but the winters have become visibly warmer, with the temperatures significantly increasing from the 1980s. The average annual precipitation rate has shown a downwards trend at a rate of −11.7 mm every 10 years. Even though the precipitation rate shows variations, the amount of precipitation is inconsistent with the most significant decrease in precipitation rates being seen during summer followed by autumn, while the rates actually slightly increased during spring and winter. Over the 42 years, the Region as a whole showed a trend of climate warming and drying with 77% of the total sites studied showing these combined trends. Before the 1980s, mainly a drying and cooling trend was observed. In the mid-to-late 80s the temperatures rose, resulting in the change to a warming and drying trend.

As one of the most promising materials for solar water oxidation, hematite has attracted intense research interest for four decades. Despite their desirable optical band gap, stability and other attractive features, there are great challenges for the implementation of hematite-based photoelectrochemical cells. In particular, the extremely low electron mobility leads to severe energy loss by electron hole recombination. Elemental doping, i.e., replacing lattice iron with foreign atoms, has been shown to be a practical solution. Here we review the significant progresses in metal and non-metal element doping-promoted hematite solar water oxidation, focusing on the role of dopants in adjusting carrier density, charge collection efficiency and surface water oxidation kinetics. The advantages and salient features of the different doping categories are compared and discussed.

For degradation of β-lactam antibiotics pollution in waters, the strained β-lactam ring is the most toxic and resistant moiety to biodegrade and redox-chemically treat among their functional groups. Hydrolytically opening β-lactam ring with Lewis acid catalysts has long been recognized as a shortcut, but at room temperature, such hydrolysis is too slow to be deployed. Here, we found when Cu2+ was immobilized on imine-linked COF (covalent organic framework) (Cu2+/Py-Bpy-COF, Cu2+ load is 1.43 wt%), as-prepared composite can utilize the light irradiation (wavelength range simulated sunlight) to in situ heat anchored Cu2+ Lewis acid sites through an excellent photothermal conversion to open the β-lactam ring followed by a desired full-decarboxylation of hydrolysates. Under 1 W/cm² simulated sunlight, Cu2+/Py-Bpy-COF powders placed in a microfiltration membrane rapidly cause a temperature rising even to ~211.7 °C in 1 min. It can effectively hydrolyze common β-lactam antibiotics in waters and even antibiotics concentration is as high as 1 mM and it takes less than 10 min. Such photo-heating hydrolysis rate is ~24 times as high as under dark and ~2 times as high as Cu2+ homogenous catalysis. Our strategy significantly decreases the interference from generally coexisting common organics in waters and potential toxicity concerns of residual carboxyl groups in hydrolysates and opens up an accessible way for the settlement of β-lactam antibiotics pollutants by the only energy source available, the sunlight. [ABSTRACT FROM AUTHOR]

Photoelectrocatalytic degradation of various dyes under visibility light irradiations with a TiO2 nanoparticles electrode were investigated to reveal the mechanism for TiO2-assisted photoelectrocatalytic degradation. The experimental results imply both the superoxide anionic radical and the dye cationic radical and the dye cationic radical were essential to the mineralization of the dyes under visible light-induced photoelectrocatalytic conditions.

A novel photooxidative system for degrading toxic organic pollutants, including organic dyes and small molecular compounds such as Rhodamine B (RhB) and 2,4-dichlorophenol (DCP), is reported. A metal-organic complex (beta-cyclodextrin-hemin, CDH), synthesized by combining beta-CD with the bioactive small molecule hemin, can efficiently activate hydrogen peroxide to oxidize and mineralize the target compounds in aqueous media at neutral pHs under ambient conditions of temperature and pressure and with visible light irradiation.

Large-scale eco-environmental vulnerability assessment is conducive to a comprehensive understanding of the quality of ecological environment, which can help accurately capture the ecologically vulnerable areas. Under climate change scenarios, this paper predicted the eco-environmental vulnerability for future mainland China at the county level, and analyzed its trends under the four scenarios. Results shows that areas with higher levels of vulnerability are mainly located in the western China and at the junction of south provinces, while the eco-environmental vulnerability of the eastern and southern coastal areas is relatively low. In terms of temporal trends, the NECR and MGR have the most stable eco-environmental vulnerability, while the eco-environmental vulnerability in the LPR, SWCR and GXR shows an obviously increasing trend under the scenario with high radiative forcing level. The most obvious increase in eco-environmental vulnerability is identified in the North China Plain under RCP 8.5. By comparison, the increment in vulnerability grades during 2020s-2090s is significantly higher than that of the period 2020s-2050s, especially under RCP 8.5 scenario. The trends of eco-environmental vulnerability show upward tendency overall, and the northwestern and southeastern regions have the biggest changes in eco-environmental vulnerability, especially under the high emission scenario. [ABSTRACT FROM AUTHOR]

Fenton degeneration of malachite green (MG) catalyzed by different types of aromatic ingredients is investigated. It is observed that the aromatic ingredients displayed catalysis immediately or after an induction gap to quicken the MG degeneration in the Fenton reaction.

Titanium dioxide photoassisted degradation of the cationic dye rhodamine B (RhB) is found to be faster in the presence of sodium dodocylbenzenesulfonate (DBS) than in pH independent processes in TiO2 dispersions containing no DBS. The degradation process was examined in aqueous dispersions under visible light irradiation at wavelengths longer than 470nm and the process is described as electron injection sensitization of TiO2.

Well-defined ultrathin nanoribbons are prepared from an amphiphilic electron donor-acceptor (D-A) supramolecule comprising perylene tetracarboxylic diimide as the backbone scaffold to enforce the one-dimensional intermolecular assembly via strong [pi]-stacking. The combination of the sensitive modulation of conductivity with the unique features intrinsic to the nanoribbon morphology has enabled efficient vapor sensing of nitro-based explosives.

A new type of fluorescence sensory material is developed from the alkoxycarbonyl-substituted, carbazole-cornered, arylene-ethynylene tetracycle (ACTC). These films have shown a compelling efficiency in detecting explosive vapor because of extended one-dimensional molecular stacking between the component molecules and intrinsic nanoporous morphology formed within the film.

The visible-light-induced electron transfer and degradation of rhodamine B (RhB) is determined by using V[O.sub.2.sup.+], Pt(IV) and both of them as electron acceptors. The results have indicated that in the V[O.sub.2.sup.+] and Pt(IV) combined system V[O.sub.2.sup.+] not only oxidized RhB leading to deethylation but also oxidized the reduced Pt(II) to regenerate Pt(IV), leading to further cleavage of chromophore structure of RhB, which behaved in a different way from the separate ones.

Linearly polarized emission is observed for the nanobelts fabricated from a perylene diimide molecule through both solution-based and surface-supported self-assembling. The emission dipole moment was measured at a direction deviating from the long axis of the nanobelt, implying a slightly tilted molecular stacking with respect to the one-dimensional growing direction of the nanobelt.

The effects of side-chain substitutions on the morphology of self-assembly of perylene dimide molecules are studied with two derivatives modified with distinctly different side-chains, N,N-di(dodecyl)-perylene-3,4,9,10-tetracarboxylic diimide (DD-PTCDI) and N,N'-di(nonyldecyl)-perylene-3,4,9,10-tetracarboxylic diimide (ND-PTCDI). The results have demonstrated the potential control over the dimensionality of self-assembly of PTCDI molecules through appropriate molecular design in line with proper assembly processing that matches the thermodynamics of the molecular structure.

The electron spin resonance (ESR) spin-trapping technique uses 5,5-dimethyl-1-pyrroline-N-oxide as the spin-trap reagent and is applied to detect radical intermediates generated during UV or visible irradiation of aqueous 4-chlorophenol (4-CP)/N-doped TiO(sub 2) suspensions. ESR reveals that the active species are responsible for the photodecomposition of 4-CP over N-doped TiO(sub 2) under visible irradiation.

Photooxidation of dibenzothiophene (DBT) and 4,6-dimethyldibenzothiophene (DMDBT) sensitized by N-methylquinolinium tetrafluoborate was investigated in O(sub 2)-saturated acetonitrile solutions. Nearly 100% oxidation of DBT and DMDBT was observed, and the oxidized products were predominantly composed of sulfides and sulfones, which are formed via photoinduced electron transfer.

A delicate composite structure that consist of long titanate fibers covered with anatase nanocrystals were achieved by a controlled reaction of titanate nanofibers with dilute acid solution, and the titanate fibers were fabricated through a hydrothermal reaction. These findings highlight the opportunities to create delicate inorganic nanostructures with advanced functions by wet chemical approaches.

A novel photocatalytic oxidation system, consisting of H2O2 and FeTPPS4 supported on a resin, is used to photodegrade the toxic and nonbiodegradable organic pollutants, Sulforhodamine B (SRB) and 2,4-dichlirophenol (DCP), in an aqueous solution. The FePR/H2O2 photocatalytic system, exhibits higher catalytic activity and better stability than FeTPPS4, provides new possibilities for the oxidative removal of persistent organic pollutants in aquatic environment under visible light irradiation.

Simple methods of modified sol-gel synthesis were applied on doped Toxic Organic (TiO2) with a nonmetal element, boron, and a metal oxide Ni2O3. The results demonstrat e that, incorporation of B into TiO2 can extend the spectral response to the visible region, and can enhance photocatalytic activity.

The photooxidative degradation of sulforhodamine-B dye (SRB) taking place in visible-light illuminated platinized titania dispersions is revisited to examine the influence of metallic platinum doped on TiO2 particles by photocatalytic deposition from a hexachloroplatinic acid solution. The platinum dopant acts as an electron sink from which molecular oxygen scavenges the electrons to yield superoxide radical anions.

Soot, which consists of organic carbon (OC) and elemental carbon (EC), is a significant component of the total aerosol mass in the atmosphere. Photochemical oxidation is an important aging pathway for soot. It is commonly believed that OC is photoactive but EC, albeit its strong light absorption, is photochemically inert. Here, by taking advantage of the different light absorption properties of OC and EC, we provide direct experimental evidence that EC also plays an important role in the photochemical aging of soot by initiating the oxidation of OC, even under red light irradiation. We show that nascent soot, in addition to undergoing photochemical oxidation under blue light with a wavelength of 440 nm, undergoes similar oxidation under red light irradiation of λ = 648 nm (L648). However, separated OC (extracted from soot by n-hexane) and EC exhibit little reactivity under L648. These observations indicate that EC plays a pivotal role in photoaging of soot by adsorbing light to initiate the oxidation of OC. Comparison of in situ IR spectra and photoelectrochemical behaviors suggests that EC-initiated photooxidation of OC proceeds through an electron transfer pathway, which is distinct from the photoaging induced by light absorption of OC. Since the absorption spectra of EC have a much larger overlap with the solar spectra than those of OC, our results provide insight into the chemical mechanism leading to rapid soot aging by organic species observed from atmospheric field measurements. [ABSTRACT FROM AUTHOR]

Electron spin resonance (ESR) spectrometry methods are used for direct probing of the delocalized charge within PTCDI nanobelt, a special nanowire with beltlike morphology. The long-range [pi]-electron delocalization has enabled the increase of electrical conductivity of the nanobelt through surface doping.