Rational construction of visible-light-driven perylene diimides/Fe2O3@C derived from MIL-88A (Fe) heterojunction with S-scheme electron transfer pathway to activate peroxymonosulfate for degradation of antibiotics.

The novel composite photocatalytic material perylene diimides/Fe2O3@C (PDIs/Fe2O3@C) was constructed by a simple hydrothermal-calcination method and an oil bath method. 20 % PDIs/Fe2O3@C displayed a 16.4-fold increase in the rate of tetracycline (TC) removal over Fe2O3@C at 8 min. The main factor that enhanced photocatalytic performance was due to the combination of PDIs with Fe2O3@C, which effectively improved the phenomenon during the self-assembly of highly agglomerative PDIs, increased the specific surface area of Fe2O3@C, exposed more reaction sites, and promoted the activation of peroxymonosulfate (PMS) by Fe2+/Fe3+; and secondly, the composite of two different materials, both organic and inorganic, which effectively promoted the photogenerated electron transfer and the separation of electron-hole pairs, the a new S-scheme electron transport pathway is formed, which effectively promoted the photogenerated electron transfer as well as the e--h+ separation, which was more favorable for the activation of PMS. The whole reaction pathway and product toxicity were thoroughly evaluated by Fukui function calculations, Liquid Chromatograph Mass Spectrometer (LC-MS), and Toxicity Estimation Software Tool (T.E.S.T.) simulation results, which demonstrated the rationality of the degradation pathway and the greatly reduced product toxicity. Moreover, the composites were effective and versatile for all other antibiotics (chlortetracycline (CTC), ciprofloxacin (CIP) and sulfadiazine (SDZ)). As an advanced oxidation process, the activation of PDIs/Fe2O3@C under visible light shows its potential application in pollutant degradation, which provides new perspectives and ideas for further effective treatment of real wastewater.

Cyano-Rich g-C3 N4 in Photochemistry: Design, Applications, and Prospects.

Cyano-rich g-C3 N4 materials are widely used in various fields of photochemistry due to the very powerful electron-absorbing ability and electron storage function of cyano, as well as its advantages in improving light absorption, adjusting the energy band structure, increasing the polarization rate and electron density in the structure, active site concentration, and promoting oxygen activation ability. Notwithstanding, there is yet a huge knowledge break in the design, preparation, detection, application, and prospect of cyano-rich g-C3 N4 . Accordingly, an overall review is arranged to substantially comprehend the research progress and position of cyano-rich g-C3 N4 materials. An overall overview of the current research position in the synthesis, characterization (determination of their location and quantity), application, and reaction mechanism analysis of cyano-rich g-C3 N4 materials to provide a quantity of novel suggestions for cyano-modified carbon nitride materials' construction is provided. In view of the prevailing challenges and outlooks of cyano-rich g-C3 N4 materials, this paper will purify the growth direction of cyano-rich g-C3 N4 , to achieve a more in-depth exploration and broaden the applications of cyano-rich g-C3 N4 .

Green synthesized hydroxyapatite for efficient immobilization of cadmium in weakly alkaline environment.

The development of cost-effective passivators for the remediation of heavy metal-contaminated soils has been a research hotspot and an unsolved challenge. Herein, a novel hydroxyapatite (GSCH) was synthesized by co-precipitating distiller effluent-derived Ca with (NH4)2HPO4 using straw-derived dissolved organic matter (S-DOM) as the dispersant. Batch adsorption experiments and soil incubation tests were performed to assess the immobilization efficiency of GSCH for Cd in weakly alkaline environments. As a result, GSCH showed an excellent adsorption efficiency to Cd with a maximum adsorption amount of ∼222 mg g-1, which was fairly competitive compared to other similar previously materials reported. The kinetic data indicated that the adsorption of Cd on GSCH was a chemical and irreversible process, while the thermodynamic data revealed a spontaneous (ΔG° < 0) and endothermic (ΔH° > 0) adsorption process. Based on mechanism analysis, both physisorption (e.g., electrostatic attraction and pore filling) and chemisorption (e.g., ion exchange and complexation) were responsible for Cd adsorption on GSCH. Particularly, the incorporated S-DOM and hydroxyapatite phase in GSCH acted synergistically in the adsorption process. The incubation results showed that GSCH application could significantly reduce the bioavailability, phytoavailability and bioaccessibility of Cd in soil by 48.4%-57.8%, 20.4%-28.6% and 12.6%-24.0%, respectively. Moreover, GSCH application also improved soil bacterial communities and enhanced soil nutrient availability. Overall, this is the first study to demonstrate the potential application value of GSCH in Cd immobilization, providing promising insights into the development of green and cost-effective hydroxyapatite-based passivators for the remediation of heavy metal-contaminated soils.

A Preliminary Study of the Impacts of Duckweed Coverage during Rice Growth on Grain Yield and Quality.

The overuse and misuse of fertilizers have been causing duckweed outbreaks in irrigation ditches and paddy fields in many rice-growing areas. However, how duckweed coverage in a paddy field affects the rice yield and grain quality is under debate because duckweed may act as either a weed, competing with rice for mineral nutrients, or a "nutrient buffer", providing significant ecological and economic benefits. To understand the effects of duckweed coverage throughout rice growth on the yield and quality of rice grains, an experiment with three Japonica rice cultivars was conducted with fertile lotus-pond bottom soil as a growth medium to provide sufficient mineral nutrients for both the duckweed and rice. Averaged across three rice cultivars, duckweed coverage decreased the panicle density but increased the spikelet density and grain weight, resulting in no significant change in the rice yield. Duckweed coverage had no impact on the processing and appearance quality in general, but significant duckweed-by-cultivar interactions were detected in the head rice percentage and grain chalkiness, indicating different sensitivities of different cultivars in response to the duckweed treatment. The decrease in breakdown and increase in setback values in the rapid visco analyzer (RVA) profile of rice flour suggested that duckweed coverage during rice growth worsened the cooking quality of the rice. However, no significant change in the palatability of the cooked rice was found. The most profound change induced by the duckweed was the nutritional quality; duckweed coverage increased the protein concentration but decreased the concentrations of Mg, Mn, Cu, and Zn in rice grains. This preliminary study suggested that duckweed coverage during rice growth has profound effects on the rice nutrient uptake and grain nutritional quality under the circumstances, and further research on the responses of the rice quality to the duckweed coverage in paddy fields in multiple locations and years is needed.

Soiltesting formula fertilization with organic fertilizer addition for target yield cannot stand long due to stem lodging of rice.

Introduction: Soil testing formula fertilization using organic fertilizer (STFFOF)could increase grain yields and protect the ecological environment but the potential risks of STFFOF remains unclear. Methods: In order to assess the risk on rice stem lodging, a STFFOF field experiment is conducted continuously for 11 years. Results: After 11 years of continuous STFFOF treatment, the stem lodging rate of rice substantially increases by 81.1%*, which completely overweigh its increase in yield. Further research found that STFFOF greatly decreases the concentration of Ca, SiO2, K, Mg, and non-structural carbohydrates in basal internodes, dramatically increases that of N, P, and weight per ear, but slightly affects the structural carbohydrates. The strong correlations imply the increasement in weight per ear, N, and P concentrations, and the significant decrease in starch in the basal internodes might directly increase the brittleness of stem internodes and further cause severe stem lodging and yield loss of rice. Discussion: Results suggest that the potential risks of rice production including stem lodging must be considered when adopting the excessive exploration mode of productivity technology of paddy fields.

C-O band structure modified broad spectral response carbon nitride with enhanced electron density in photocatalytic peroxymonosulfate activation for bisphenol pollutants removal.

Here, a simple one-step calcination method uses glycolic acid (GA) and urea to synthesize C-O band structure modified carbon nitride with broad spectral response, which is used to construct a peroxymonosulfate/visible light (PMS/vis) system. The solid-state 13C NMR proved that C-O band structure was successfully introduced into the carbon nitride. Density functional theory (DFT) calculation show that the introduction of C-O band structure shortens the band gap of 0.05 g GA modified CN (0.05 GA-CN). Besides, Ultraviolet photoelectron spectroscopy (UPS) further illustrate that the 0.05 GA-CN has a higher charge density and promotes the degradation of pollutants. In PMS/vis system, 0.05 GA-CN can completely degrade bisphenol A (BPA) within 36 min. In addition, 0.05 GA-CN can also degrade bisphenol E (BPE) and bisphenol F (BPF). The cyclic voltammetry (CV) curve show that the introduction of C-O band structure enhances the activation ability of PMS. At the same time, 0.05 GA-CN/PMS has enhanced the activity of degrading BPA under blue light (450-462 nm), green light (510-520 nm) and red light (610-625 nm). This research provides a new method to synthesize carbon nitride with enhanced electron density for degradation of bisphenol pollutants in PMS/vis system.

Response of rice growth and leaf physiology to elevated CO2 concentrations: A meta-analysis of 20-year FACE studies.

The Free Air CO2 Enrichment (FACE) facility enables the study of plant responses to climate change under open field conditions. This meta-analysis was conducted to quantitatively assess the effects of elevated CO2 concentration ([CO2]) on 47 variables describing rice growth physiology and whether CO2 effects were influenced by cultivar, plant growth stage, nitrogen application rate or temperature. On average, elevated [CO2] increased root and shoot biomass by 28% and 19%, respectively. Among shoot organs, the [CO2]-induced increase in leaf biomass was only 9%, significantly smaller than a 24% increase in stems or a 25% increase in panicles. The higher biomass for FACE rice was consistent with the stimulation in plant height (4%), maximum tiller number (11%), leaf area index (9%) and light-saturated photosynthetic rate (Asat, 22%). When compared within rice groups, hybrid rice showed the greatest CO2 response in growth and leaf physiological variables. Elevated [CO2] increased plant biomass and Asat at each rice growth stage, but the increment tended to decline with the advancement of rice growth and development. The increase in aboveground biomass at elevated [CO2] was enhanced by a higher nitrogen supply but reduced with a temperature elevation of 1-2 °C. Rice growth benefited more from elevated [CO2] in Chinese FACE studies than in Japanese FACE studies, which may result from the different cultivars and nitrogen application rates used in the two countries. Combined with a previous meta-analysis of the rice yield response to FACE, the [CO2] level predicted in the middle of this century will improve rice productivity by stimulating leaf photosynthesis. However, the effects of CO2 on the photosynthetic rate and rice growth tend to shrink over the plant life cycle. Selecting heat-resistant, high-yield hybrid rice cultivars with large sink capacity, supplemented with appropriate nitrogen input, will maximize the CO2 fertilizer effect in the future.

Nutritional Properties of Larval Epidermis and Meat of the Edible Insect Clanis bilineata tsingtauica (Lepidoptera: Sphingidae).

Insects represent a sustainable, protein-rich food source widely consumed in Asia, Africa, and South America. Eating Clanis bilineata tsingtauica Mell is common in the eastern part of China. A comparative characterization of nutrients in the meat and epidermis of C. bilineata tsingtauica was performed in this study. The results showed this insect to be high in nutrients, particularly in the epidermis where protein total was 71.82%. Sixteen different amino acids were quantified in C. bilineata tsingtauica, and the ratio of essential to nonessential amino acids in the epidermis and meat was 68.14% and 59.27%, respectively. The amino acid composition of C. bilineata tsingtauica is balanced, representing a high-quality protein source. Eight minerals were quantified in C. bilineata tsingtauica, including four macro and four trace elements. Fe in the epidermis and Zn in the meat were abundant at 163.82 and 299.31 µg/g DW, respectively. The presence of phytic acid impacted the absorption of mineral elements in food. We also detected phytic acid in C. bilineata tsingtauica. The molar ratio of phytic acid to zinc (PA/Zn) in C. bilineata tsingtauica was very low (3.28) compared to Glycine max and Cryptotympana atrata, which indicated that mineral utilization was high. In conclusion, this study confirms that C. bilineata tsingtauica is a highly nutritious food source for human consumption, and the results provide a basis for further consumption and industrialization of this edible insect.

Alterations in Source-Sink Relations Affect Rice Yield Response to Elevated CO2: A Free-Air CO2 Enrichment Study.

To understand the effects of source-sink relationships on rice yield response to elevated CO2 levels (eCO2), we conducted a field study using a popular japonica cultivar grown in a free-air CO2 enrichment environment in 2017-2018. The source-sink ratio of rice was set artificially via source-sink treatments (SSTs) at the heading stage. Five SSTs were performed in 2017 (EXP1): cutting off the flag leaf (LC1) and the top three functional leaves (LC3), removing one branch in every three branches of a panicle (SR1/3) and one branch in every two branches of a panicle (SR1/2), and the control (CK) without any leaf cutting or spikelet removal. The eCO2 significantly increased grain yield by 15.7% on average over all treatments; it significantly increased grain yield of CK, LC1, LC3, SR1/3, and SR1/2 crops by 13.9, 18.1, 25.3, 12.0, and 10.9%, respectively. The yield response to eCO2 was associated with a significant increase of panicle number and fully-filled grain percentage (FGP), and the response of crops under different SSTs was significantly positively correlated with FGP and the average grain weight of the seeds. Two SSTs (CK and LC3) were performed in 2018 (EXP2), which confirmed that the yield response of LC3 crops (25.1%) to eCO2 was significantly higher than that of CK (15.9%). Among the different grain positions, yield response to eCO2 of grains attached to the lower secondary rachis was greater than that of grains attached to the upper primary rachis. Reducing the source-sink ratio via leaf-cutting enhanced the net photosynthetic rate response of the remaining leaves to eCO2 and increased the grain filling ability. Conversely, spikelet removal increased the non-structural carbohydrate (NSC) content of the stem, causing feedback inhibition and photosynthetic down-regulation. This study suggests that reducing the source-sink ratio by adopting appropriate management measures can increase the response of rice to eCO2.

Impact of Elevated CO2 and Reducing the Source-Sink Ratio by Partial Defoliation on Rice Grain Quality - A 3-Year Free-Air CO2 Enrichment Study.

Evaluating the impact of increasing CO2 on rice quality is becoming a global concern. However, whether adjusting the source-sink ratio will affect the response of rice grain quality to elevated CO2 concentrations remains unknown. In 2016-2018, we conducted a free-air CO2 enrichment experiment using a popular japonica cultivar grown at ambient and elevated CO2 levels (eCO2, increased by 200 ppm), reducing the source-sink ratio via cutting leaves (LC) at the heading stage, to investigate the effects of eCO2 and LC and their interactions on rice processing, appearance, nutrition, and eating quality. Averaged across 3 years, eCO2 significantly decreased brown rice percentage (-0.5%), milled rice percentage (-2.1%), and head rice percentage (-4.2%) but increased chalky grain percentage (+ 22.3%) and chalkiness degree (+ 26.3%). Markedly, eCO2 increased peak viscosity (+ 2.9%) and minimum viscosity (+ 3.8%) but decreased setback (-96.1%) of powder rice and increased the appearance (+ 4.5%), stickiness (+ 3.5%) and balance degree (+ 4.8%) of cooked rice, while decreasing the hardness (-6.7%), resulting in better palatability (+ 4.0%). Further, eCO2 significantly decreased the concentrations of protein, Ca, S, and Cu by 5.3, 4.7, 2.2, and 9.6%, respectively, but increased K concentration by 3.9%. Responses of nutritional quality in different grain positions (brown and milled rice) to eCO2 showed the same trend. Compared with control treatment, LC significantly increased chalky grain percentage, chalkiness degree, protein concentration, mineral element levels (except for B and Mn), and phytic acid concentration. Our results indicate that eCO2 reduced rice processing suitability, appearance, and nutritional quality but improved the eating quality. Rice quality varied significantly among years; however, few CO2 by year, CO2 by LC, or CO2 by grain position interactions were detected, indicating that the effects of eCO2 on rice quality varied little with the growing seasons, the decrease in the source-sink ratios or the different grain positions.

How do elevated atmosphere CO2 and temperature alter the physiochemical properties of starch granules and rice taste?

Elevated atmospheric CO2 (EC) and temperature (ET) strongly affect agricultural production, but the mechanism through which EC and/or ET influence starch granules and their relationship to cooked rice taste remain largely unknown. Therefore, a field experiment using a popular japonica cultivar grown in a temperature/free-air CO2 enrichment environment was conducted to investigate the responses of volume and fine structure of starch granules and their formation physiology to EC (+200 ppm) and/or ET (+1 °C) in 2015-2016. EC markedly enhanced the activity of soluble-starch synthase and granule-bound starch synthase by 28.0% and 27.9% respectively, thereby increasing the long chains and the volume of starch granules. However, EC decreased the activity of starch-branch enzyme by 7.5% possibly via the pathway of ethylene signalling (EC prominently decreased the ethylene evolution rate of rice grains by 28.8%), resulting in a remarkable decrease in α-1'6 glucosidic bonds and significant increase in the iodine-binding capacity and double helix in starch molecules. These EC-induced changes in morphology and fine structure of starch granules synergistically altered the thermal properties of rice flour and eventually improved the cohesiveness and taste of cooked rice, as suggested by the significant relationships between them. ET partially offset the beneficial EC effects in most cases. However, few remarkable CO2 × temperature or CO2 × year effects were detected, indicating that the effects of EC on starch granules and rice taste less varied with meteorological conditions. These findings have important implications on rice palatability and for the development of adaptive strategies in the starch industry in future environment.

Realizing the synergistic effect of electronic modulation over graphitic carbon nitride for highly efficient photodegradation of bisphenol A and 2-mercaptobenzothiazole: Mechanism, degradation pathway and density functional theory calculation.

Here, we successfully synthesized a brown carbon nitride (CY-C3N4) co-modified with oxygen bridge and porous defects via a universal acylation method. Excitingly, density functional theory (DFT) calculation shows that the introduction of oxygen bridges in the calcination polymerization process can adjust the electronic structure and energy band position of the new material. Further, the results of elemental analysis and X-ray photoemission spectroscopy test indicate that the oxygen bridge structure was successfully introduced into the skeleton of carbon nitride. The results show that 0.1CY-C3N4 can remove bisphenol A (BPA) and 2-mercaptobenzothiazole (MBT) with a removal rate of approximately 99% in 90 min and 20 min, respectively. Its degradation rate is 17.94 times and 3.85 times faster than that the original carbon nitride, respectively. Further, through HPLC-MS analysis, the intermediate products of the reaction process were analyzed in depth to propose a possible photocatalytic degradation route. Free radical capturing test and ESR spectroscopy indicate that the formative hydroxyl radical (OH), superoxide radical (O2-), singlet oxygen (1O2) and hole (h+) all play a key role in the photodegradation. This study provides a new way to synthesize brown carbon nitrides with oxygen bridges and porous defects for environmental applications.

An efficient broad spectrum-driven carbon and oxygen co-doped g-C3N4 for the photodegradation of endocrine disrupting: Mechanism, degradation pathway, DFT calculation and toluene selective oxidation.

In this study, a new type of carbon and oxygen co-doped g-C3N4 (PACN) was successfully synthesized by a one-step thermal polymerization method for the photodegradation of Bisphenol A (BPA) and selective oxidation of toluene to benzaldehyde. The degradation rate of BPA was 23.58 times higher than that of pristine g-C3N4 and the efficiency benzaldehyde formation rate without the need of any solvent increased to 5.43 times that of g-C3N4. At the same time, the band structure calculation of its simulated structure is performed by DFT, which shows that the introduction of oxygen linking band can adjust its band structure and obtain a smaller band gap. In addition, the PACN displays an enhanced photocatalytic degradation of BPA under the long wavelength (λ ≥ 550 nm) and NIR light irradiation (λ ≥ 760 nm), which indicates that the synthesized materials have a broad spectrum of photocatalytic activity. According to the results of secondary ion mass spectrometry (SIMS) and nuclear magnetic resonance spectroscopy (NMR), C atoms and O atoms were introduced into the original g-C3N4 skeleton. In addition, the intermediate products were detected by mass spectrometry (HPLC-MS), and the BPA degradation pathway was proposed. A feasible photocatalytic reaction mechanism was also proposed.

Novel broad-spectrum-driven g-C3N4 with oxygen-linked band and porous defect for photodegradation of bisphenol A, 2-mercaptophenthiazole and ciprofloxacin.

Abundant active oxygen free radicals could efficiently remove refractory organic pollutants. In previous research, the original carbon nitride can form more hydrogen peroxide, however, owing to the limitation of its band structure, the original carbon nitride cannot decompose the hydrogen peroxide to generate more active oxygen free radicals. Herein, this work reports a simple bottom-up synthesis method, which synthesize a broad-spectrum-response carbon nitride (CN-CA) with oxygen-linked band and porous defect structure, while adjusting the band structure, and the introduction of the oxygen-linked band structure can also decompose the hydrogen peroxide produced by the original carbon nitride to form more active oxygen free radicals. Instrumental characterization and analysis of experimental results revealed the important role of oxygen-linked band and porous defects in adjusting the CN-CA energy band structure and improving its visible light absorption. The optimal CN-CA displays an outstanding photocatalytic degradation ability, that degradation rate of bisphenol A (BPA) reaches 99.8% within 150 min, the reaction rate constant of which is 6.77 times higher than that of pure g-C3N4, as also demonstrated with 2-mercaptophenthiazole (MBT) and ciprofloxacin (CIP). Meanwhile, the excellent degradation performance under blue LED (450-462 nm) and green LED (510-520 nm) exhibits the broad-spectrum characteristics of CN-CA. The degradation pathways of BPA and MBT were analyzed via HPLC-MS. Moreover, the primary active species were detected as O2-, OH and h+ based on the trapping experiments and ESR. This research provides a new strategy for g-C3N4 modified by porous defects and oxygen-linked band structure for environmental remediation.

Novel broad-spectrum-driven oxygen-linked band and porous defect co-modified orange carbon nitride for photodegradation of Bisphenol A and 2-Mercaptobenzothiazole.

Here, we successfully synthesized the oxygen-linked band and porous defect co-modified orange carbon nitride (AF-C3N4) using a simple method. Further, the band structure calculation of its simulated structure is performed by DFT, which shows that the introduction of oxygen-linked band can adjust its band structure. The photocatalytic degradation rates of 0.3AF-C3N4 for bisphenol A and 2-mercaptobenzothiazole were 8 times and 2.73 times that of the original g-C3N4, respectively. Moreover, 0.3AF-C3N4 also shows photocatalytic activity under different wavelength light (blue, green and red light), which indicates that the synthesized materials have a broad spectrum of photocatalytic activity. Further, we proposed a possible photocatalytic degradation pathway by HPLC-MS analysis. Free radical quenching test and ESR spectra show that the generated superoxide radicals (•O2-), hydroxyl radicals (•OH) and holes (h+) cause photodegradation, while enhancing singlet oxygen (1O2) and weaken the content of hydrogen peroxide has further proved that active oxygen groups play an important role in the photocatalytic degradation process. Additionally, the 0.3AF-C3N4 can also be a photoelectrochemical sensor to detect the concentration of bisphenol A (λ ≥ 550 nm). This study provides a new strategy for the synthesis of orange carbon nitride by oxygen-linked band and porous defect co-modification for photocatalytic applications.

Porous defective carbon nitride obtained by a universal method for photocatalytic hydrogen production from water splitting.

For the first time, herein this work, we have developed an effective and adaptable method to introduce defects onto the polymeric carbon nitride by simply grinding urea with urea nitrate which resulting new carbon nitride composite (UNU-C3N4) and melamine with urea nitrate which resulting new carbon nitride composite (UNM-C3N4). The UNU-C3N4 reveals high performance towards photocatalytic hydrogen production and as well as photocatalytic removal of contaminants. The results confirm that the defects enhanced the specific surface area, and improved performance of adsorbed oxygen which beneficial to generate more active radicals and more conducive sties to improve d the overall photocatalytic performance. The high N, H, and O content-enhanced electron polarization effects, by introducing the additional N, H, and O atoms into the g-C3N4 matrix, which will increase the charge transfer rate and charge separation efficiency. At the same time, the results of ESR also expression that the new type of as-prepared carbon nitride samples exhibit abundant of hydrogen radical (H) formation, which is also assist to improve the photocatalytic hydrogen production performance. As expected, the H2 evolution rate of UNU-C3N4(or UNM-C3N4) underneath simulated solar light irradiation is 9.93 times (13.76 times) than that of U-C3N4 (urea as raw material) (or M-C3N4 (melamine as raw material)). The high hydrogen evolution rates of UNU-C3N4 and UNM-C3N4 are 830.94 and 556.79 µmol g-1  h-1 under the visible-light irradiation, respectively. Meanwhile, the synthesized UNU-C3N4 and UNM-C3N4 material are demonstrated an efficient ability to degrade pollutants. In general, this work provides a viable way to introduce defects and hydrogen bands into the structure of carbon nitride.

In situ construction efficient visible-light-driven three-dimensional Polypyrrole/Zn3In2S6 nanoflower to systematically explore the photoreduction of Cr(VI): Performance, factors and mechanism.

Photoreduction of highly toxic Cr(VI) has been regarded as an efficient and green method to achieve water purification. In this process, better charge carrier separation is vital to achieving excellent performance. Besides, it is vital to systematically explore the influencing factors and reaction mechanism. Herein, a novel 3D PPy/Zn3In2S6 nanoflower composite was successfully fabricated via in-situ polymerization. The remarkable conductivity of PPy provides a good electron transport path to facilitate the separation and migration of charge carriers, which benefits to the activity improvement. The results show that 5% PPy/Zn3In2S6 exhibits superior photocatalytic activity with almost 100% Cr(VI) reduction just within 24 min and 99.4% of Methyl orange (MO) is degraded in 25 min. On this basis, factors of different catalyst dosage, concentration, ions and pH under the reduction system were systematically investigated. Especially, different organic acids were in-depth analyzed and the activity could be significantly enhanced just adding 0.1 mmol organic acids. 5% 3D PPy/Zn3In2S6 nanoflower composites (with tartaric acid) exhibits superior photocatalytic activity, which can achieve 100% photoreduction of Cr(VI) just within 6 min. Finally, a possible reaction mechanism was proposed. Moreover, 3D PPy/Zn3In2S6 nanoflower also presented an efficient photodegradation activity for organic pollution.

[Effects of elevated CO2 concentration on grain filling capacity and quality of rice grains located at different positions on a panicle.] / 高浓度CO2对稻穗不同位置籽粒结实和米质性状的影响.

The rising atmospheric CO2 concentration affects spikelets development, grain filling process, and rice quality. However, it is unclear that whether such effects are related to grain positions on rice panicle. By using a rice FACE (Free-Air CO2 Enrichment) platform, we grew a japoni-ca rice cultivar Wuyunjing 23, characterized with high yield and good quality, under ambient (Ambient) and elevated CO2 concentrations (+200 µmol·mol-1, FACE). The effects of increased CO2 concentration on spikelet density, grain filling capacity, the appearance and eating quality of rice grains were examined and the association of such effects with grain positions on rice panicle were investigated. The results showed that CO2 enrichment increased grain yield of Wuyunjing 23 by 18.3%. The panicle number per unit land area and filled-grain weight increased by 21.4% and 9.4%, respectively; whereas the number of spikelets per panicle and filled-grain percentage decreased by 9.0% and 2.2%, respectively. The decreased filled-grain percentage of rice grown under FACE treatment was mainly related to the increases of empty-grain percentage in all parts of rice panicle. The decrease of rice spikelets number per panicle by FACE treatment was mainly due to the substantial decrease of surviving spikelets of secondary branches in upper and middle parts of rice panicles instead of other positions. The CO2-induced changes of filled-grain weight and filled-grain percentage were similar among grains located at different positions on rice panicle. FACE treatment reduced the green grain rate and increased the grain length and width, with the grains at different positions on rice papnicle showing similar responses. FACE significantly increased chalky grain percentage by 59% and chalkiness degree by 55%, with the increases for both parameters following the order of primary branches＞secondary branches and upper part＞middle part＞lower part. FACE treatment slightly increased amylose content while decreased peak viscosity, hot viscosity, breakdown, final viscosity and setback, but most of these effects were nonsignificant. The gelatinization temperature of rice also reduced by 5% under FACE, and the decrease of inferior spikelets was greater than that of superior spikelets. In summary, the yield increase of Wuyunjing 23 under high CO2 concentration was mainly related to the increases of panicle number and individual grain weight, while the panicle size was reduced. Elevated CO2 concentration reduced green grain percentage but increased grain chalkiness, and had little effect on cooking and eating quality. The grain positions on rice panicle affected the responses of spikelets development, grain filling capacity and grain quality of rice to elevated CO2 concentration, but the effects varied across different indices.

[Effects of ozone stress on amylose content and starch RVA profile in grains located at diffe-rent positions on a panicle]. / 臭氧胁迫对稻穗不同部位糙米直链淀粉含量和RVA谱特征值的影响.

The increase of ground-level ozone concentration significantly reduces rice yield, but its effect on grain quality in association with the positions on a panicle was largely unknown. The effects of ozone stress on amylose content and RVA profile of rice grains located at different positions of panicles were studied by using a sunlit gas fumigation platform. Eight varieties representing different types of rice were fumigated under ambient (9 nL·L-1) or elevated ozone (100 nL·L-1) concentrations from transplanting until maturity. The results showed that elevated ozone treatment significantly reduced amylose content, maximum viscosity, hot viscosity, breakdown and cold viscosity by 5.9%, 7.6%, 5.9%, 11.6%, 2.9%, respectively, but increased the setback and gelatinization temperature by 24.9% and 1.0%. There were significant differences among varieties for amylose content and all parameters in RVA profile. The grains located at different positions on a panicle differed in amylose content, maximum viscosity, hot viscosity, breakdown and cold viscosity. The superior grains located at the upper part of a panicle had the highest value and the inferior grains located at the lower part of a panicle had the lowest value. However, the setback in RVA profile showed a different trend, with the superior grains having the lowest setback but inferior grains having the highest setback. In most cases, there were significant interactive effects of ozone by year or ozone by variety on amylose content and RVA profile. No significant ozone by grain position interaction on RVA profile was found, although the responses of superior grains to ozone stress was slightly smaller than those of inferior grains or grains located at the middle part of a panicle. The results demonstrated that ozone fumigation of 100 nL·L-1 during rice growing season deteriorated rice quality, with the magnitude of deterioration varying with growth seasons and varieties and little impacts of grain positions on a panicle.

Author Correction: Grain and starch granule morphology in superior and inferior kernels of maize in response to nitrogen.

A correction to this article has been published and is linked from the HTML and PDF versions of this paper. The error has been fixed in the paper.