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Enzymatic reductions catalyzed by reductases generally depend on reduced nicotinamide cofactors as a hydride source. However, for industrial viability, it is more cost-effective to use water as the hydrogen source, bypassing the requirement for the cofactor. Here we report a hybrid photo-biocatalyst system based on infrared (IR) light and responsive reductive graphene quantum dots (rGQDs), for performing the direct transfer of hydrogen from water to prochiral substrates. The photo-biocatalyst, assembled from rGQDs and cross-linked aldo-keto reductase (AKR), mediates the synthesis of the pharmaceutical intermediate, (R)−1-[3,5-bis(trifluoromethyl)-phenyl] ethanol ((R)−3,5-BTPE), in 82% yield and >99.99% ee under IR illumination. Our photo-enzymatic systems can also be effectively used to drive the enzymatic reduction of imines and alkenes. Since the hybrid photo-biocatalysts are insoluble, they can be readily recovered and recycled. This work opens new avenues to create artificial photo-biocatalyst systems, enabling the facile coupling of renewable solar energy and sustainable chemical production. Enzymatic reductions catalyzed by reductases generally depend on reduced nicotinamide cofactors as a hydride source. In this work, the authors report a hybrid photo-biocatalyst system based on infrared light, responsive reductive graphene quantum dots and cross-linked aldo-keto reductase for performing the direct transfer of hydrogen from water to prochiral substrates.

Nitriles are of significant interest in the flavor and fragrance industries with potential application in cosmetics due to their higher stability than analogous aldehydes. However, the traditional methods to prepare nitriles need toxic reagents and hash conditions. This work aimed to develop a chemoenzymatic strategy to synthesize nitriles from natural aldehydes with aldoxime as the intermediate. A non-classical aldoxime dehydratase (Oxd) was discovered from the fungus Aspergillus ibericus (OxdAsp) to catalyze the dehydration of aldoximes to corresponding nitriles under mild conditions. The amino acid sequence of OxdAsp exhibits an approximately 20% identity with bacterial Oxds. OxdAsp contains a heme prosthetic group bound with the axial H287 in the catalytic pocket. The structure models of OxdAsp with substrates suggest that its catalytic triad is Y138-R141-E192, which is different from the classically bacterial Oxds of His-Arg-Ser/Thr. The catalytic mechanism of OxdAsp was proposed based on the mutagenesis of key residues. The hydroxyl group of the substrate is fixed by E192 to increase its basicity. Y138 acts as a general acid-based catalyst, and its phenolic proton is polarized by the adjacent R141. The protonated Y138 would donate a proton to the hydroxyl group of the substrate and eliminate a water molecule from aldoxime to produce nitrile. The recombinant OxdAsp can efficiently dehydrate citronellal oxime and cinnamaldoxime to citronellyl nitrile and cinnamonitrile in aqueous media, which are applied as fragrance ingredients in the food and cosmetic fields.Key points• A novel aldoxime dehydratase from the Aspergillus genus was first characterized as a heme-binding protein.• The catalytic mechanism was predicted based on the molecular interactions of the catalytic pocket with the substrate.• A chemoenzymatic strategy was developed to synthesize nitriles from natural aldehydes with aldoxime as the intermediate.

A linear magnetization model is built to replace the Jiles–Atherton model in order to describe the relationship between the magnetic field intensity and the magnetization intensity of the giant magnetostrictive vibrator (GMV). The systematic modeling of the GMV is composed of three aspects, i.e., the structural mechanic model, the magnetostrictive model, and the Jiles–Atherton model. The Jiles–Atherton model has five parameters to be defined; hence, its solution is so complex that it is not convenient in application. Therefore, the immune genetic algorithm (IGA) is applied in the identification of the five parameters of the Jiles–Atherton model and it showed a higher stability compared with the identification result of the differential evolution algorithm (DEA). The identification parameters of the two algorithms were employed, respectively, to calculate the excitation force and it was found that the relative error of IGA was evidently smaller than that of DEA, indicating that the former was more reliable than the latter. According to the identification results of IGA and based on the least square method (LSM), curve-fittings to the magnetic field intensity and magnetization intensity were conducted by using the linear function. And the linear magnetization model was built to replace the Jiles–Atherton model. Research results show that the linear model of the GMV can be established by combining the linear magnetization model with the structural mechanic model as well as the giant magnetostrictive model. The linear magnetization model, which has great engineering application value, can be applied in the open-loop control of the vibrator.

As the terminal reservoir of the South-to-North Water Diversion’s Eastern Route, Dongping Lake is critical for safeguarding the northern water supply. Analysis of 33 water–sediment sites revealed the following. (1) Waterborne heavy metals (HMs) below WHO limits, confirming the good water quality. (2) Sediment HM enrichment exceeding background levels, with Cd posing high ecological risk (mean Er = 135), and moderate overall pollution. (3) Speciation showed V, Cr, Co, Ni, Cu, Zn, and Pb predominantly in residual fractions, while Cd exhibited high bioavailability and Pb was in reducible state. Ecological risk assessment indicated that V and Cr tend not to cause environmental pollution; Co, Ni, Cu, Zn, and Pb only cause slight pollution; and Cd causes serious point-source pollution. The carcinogenic risk of surface sediments to children is not negligible. (4) Source apportionment identified industrial emissions as the primary HM contributors, with Cd deriving from agricultural runoff (phosphate fertilizers) and industrial discharges. This study offers valuable baseline information for water quality management in mega-water-transfer projects, directly supporting the Jiaodong Main Line and Yellow River Crossing operations.

Ideal immobilization with enhanced biocatalyst activity and thermostability enables natural enzymes to serve as a powerful tool to yield synthetically useful chemicals in industry. Such an enzymatic method strategy becomes easier and more convenient with the use of genetic and protein engineering. Here, we developed a covalent programmable polyproteam of tyrosine ammonia lyases (TAL-CLEs) by fusing SpyTag and SpyCatcher peptides into the N-terminal and C-terminal of the TAL, respectively. The resulting circular enzymes were clear after the spontaneous isopeptide bonds formed between the SpyTag and SpyCatcher. Furthermore, the catalytic performance of the TAL-CLEs was measured via a synthesis sample of p-Coumaric acid. Our TAL-CLEs showed excellent catalytic efficiency, with 98.31 ± 1.14% yield of the target product—which is 4.15 ± 0.08 times higher than that of traditional glutaraldehyde-mediated enzyme aggregates. They also showed over four times as much enzyme-activity as wild-type TAL does and demonstrated good reusability, and so may become a good candidate for industrial enzymes.

The soil-water characteristic curve (SWCC) is an important hydraulic parameter for modeling water flow and contaminant transport in the unsaturated soil. However, direct measurement of the SWCC is still difficult. The commonly used measuring instrument in the laboratory is the pressure plate extractor. In this paper, the original pressure plate extractor has been improved based on the one-step outflow test. Compared with the original pressure plate extractor, three devices, water storage, data acquisition system, and bubbles scouring device, are added to the improved pressure plate extractor. The improved equipment eliminates the problems of long test time consumption and inaccurate test data. A one-step outflow test is performed utilizing the improved pressure plate extractor. The test data (the amount of spilled water and the time of pressurization) are substituted into the one-dimensional moisture migration analysis software HYDRUS-1D. The parameters (α, m, and n) are identified by the numerical inversion method in the inversion module of the HYDRUS-1D, which are associated with the VG model to fit SWCC. The fitted SWCC is highly consistent with the measured SWCC, which is obtained from the conventional test of the original pressure plate extractor. Results confirm that the improved pressure plate extractor not only saves considerable time but also effectively measures the SWCC. The improved pressure plate extractor also involves a simple operation. The influence factors of controlling the geometry of SWCC are also discussed, the results of the discussion confirm that the geometry of SWCC is directly controlled by pore distribution, and the consolidation pressure is an indirect factor.

This study aimed to identify how the psychological characteristics of college students are reflected in understanding sustainable development goals (SDGs) by examining college students’ psychological characteristics, including attitude, interests, motivations, and self-efficacy, through the Sustainable Development Goals Psychological Inventory (SDGPI). The relationships among SDGs attitude, SDGs interest, SDGs motivation, and SDGs self-efficacy were analyzed by Pearson product-moment correlation coefficients. In addition, the Mann-Whitney U test and Kruskal-Wallis one-way analysis of variance were used to explore the differences among the college student groups in terms of gender, grade, and major in relation to attitude and personal characteristics. Attitude scores based on regression analysis were used to predict college students’ interest, motivation, and self-efficacy in relation to the SDGs. According to the results, (a) the college students considered the three most important SDGs to be good health and well-being (SDG 3) (49.72%), quality education (SDG 4) (41.39%), and no poverty (SDG 1) (32.22%), while the three least important SDGs were decent work and economic growth (SDG 8) (41.11%), partnerships for the goals (SDG 17) (38.06%), and response consumption and institutions (SDG 12) (30.83%); (b) the SDGPI had a high reliability, with a Cronbach’s alpha of 0.942; (c) there was a significant positive correlation between attitude and the variables of interest, motivation, and self-efficacy; (d) differences in attitudes, interest, and motivation between men and women were distinct and women scored much higher in these three subscales than men; (e) attitude could explain significant variance in interest, motivation and self-efficacy. In addition, attitude, interest, and motivation could account for self-efficacy. This study supports the development of sustainability education (SE) at the college level by providing new insights into college students’ psychological characteristics in relation to the SDGs.

In this qualitative study, we aim to identify suitable pedagogical approaches to teaching and learning green chemistry among college students and preservice teachers by examining the teaching methods that have been used to promote green chemistry education (GCE) and how these methods have supported green chemistry learning (GCL). We found 45 articles published in peer-reviewed scientific journals since 2000 that specifically described teaching methods for GCE. The content of the articles was analyzed based on the categories of the teaching methods used and the revised version of Bloom’s taxonomy. Among the selected articles, collaborative and interdisciplinary learning, and problem-based learning were utilized in 38 and 35 articles, respectively. These were the most frequently used teaching methods, alongside a general combination of multiple teaching methods and teacher presentations. Developing collaborative and interdisciplinary learning skills, techniques for increasing environmental awareness, problem-centered learning skills, and systems thinking skills featuring the teaching methods were seen to promote GCL in 44, 40, 34, and 29 articles, respectively. The results showed that the integration of green chemistry teaching (GCT), e.g., with sustainable education, promoted GCL by fostering environmental consciousness and behavioral change and cognitive processes in a sustainable direction.

To conveniently prepare the immobilized enzyme for green synthesis of vitamin A palmitate, thermomyces lanuginosus lipase (TLL) was assembled with apatite derived from calcium phosphate in solution to form TLL@apatite hybrid nanoflowers (hNFs) by mimetic biomineralization. The obtained hNFs was characterized by SEM and applied in the enzymatic synthesis of vitamin A palmitate. Under optimal condition, when palmitic acid and vitamin A acetate were used as substrates, the yield of the target product was up to 90.4%, about 1.5 folds of that using free TLL. In addition, when each cycle for catalytic synthesis was carried out in petroleum ether with 20% water content as solvent for 12 h, the hNFs still retains 65.8% of initial catalytic synthetic ability after 10 cycles. These results demonstrated the hNFs was a kind of green biocatalyst with high catalytic activity and high stability with great potential in the green pharmaceuticals industry.

【目的】探明膜下滴灌技术的施肥周期、滴头间距和毛管布置方式对苹果生长、果实产量品质的影响，并确定静宁县苹果膜下滴灌技术优选参数组合。【方法】2023年在甘肃静宁县以6 a生盛果期短枝富士为试材，采用施肥周期（T）、滴头间距（D）、毛管布置方式（P）3个试验因素，施肥周期设置15 d（T15）、30 d（T30）2个水平，滴头间距设置30 cm（D30）、50 cm（D50）2个水平，毛管布置方式设置1行1管（P1）、1行2管（P2），共8个处理的三因素两水平完全区组田间试验，分析3个因素对株高增长、茎粗、春梢、LAI、产量、单果质量、纵径、横径、可滴定酸、可溶性糖、糖酸比、硬度、Vc等苹果生长、产量品质指标的影响，并采用隶属函数分析法进行综合评价排序。【结果】膜下滴灌技术参数T、D、P对苹果下部LAI、单果质量、可溶性糖、糖酸比、Vc影响显著，与T30处理相比，T15处理下部LAI（0.71）显著提高，单果质量（17.25 g）、可溶性糖（1.76 g/kg）、糖酸比（0.44）、Vc（0.44 mg/100 g）显著降低；与D50处理相比，D30处理下部LAI（0.63）、可溶性糖（1.76 g/kg）显著提高，单果质量（30.51 g）、糖酸比（2.16）、Vc（1.22 mg/100 g）显著降低；与P2处理相比，P1处理下部LAI（0.38）、单果质量（16.11 g）、可溶性糖（4.26 g/kg）、糖酸比（0.78）显著提高，Vc（1.82 mg/100 g）降低；T与D的交互作用对下部LAI、可溶性糖、糖酸比影响显著；三者的交互作用对单果质量、可溶性糖、糖酸比影响显著。T15D50P2处理在茎粗、最大叶面积、产量、单果质量、横径、Vc量等指标与其他处理差异显著，平均提高2.03 mm、2.97 cm2、7 224.27 kg/hm2、36.91 g、5.77 mm、2.79 mg/100 g。【结论】采用隶属函数分析法对苹果生长、果实产量品质进行综合评价排序，筛选出综合最优膜下滴灌施肥技术参数组合为施肥周期15 d、滴头间隔50 cm、1行2管的处理。