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β-SiC rods were synthesized by microwave heating using activated carbon, boric acid, and tetraethoxysilane (TEOS) as raw materials. A sol–gel method was carried out to coat silicon dioxide (SiO2) on activated carbon and mix with boric acid. The mixed raw powders were pre-formed by uniaxial pressing into cylindrical pellets in the dimension of Φ 30 × 25 mm. The heating temperature was 1100 °C with different holding times of 10 min, 20 min, and 30 min, respectively. Techniques of XRD, SEM, DSC-TG were carried out to characterize samples. It was found that β-SiC rods can be prepared by microwave heating with the presence of liquid phase. Hybrid microwave thermal effects give rise to complicated physical and chemical reactions at high temperature. Microwave plasma and microwave coupling effects occurred due to the gases and liquid during the reaction. The growth of SiC is realized by the diffusion–precipitation mechanism. SiC rods are well formed under sufficient atomic diffusion on the surface and within the sample by self-coupling. Perfect homogeneous growth occurs with no stack fault appearing within prepared SiC rods.

Two rice genotypes Huanghuazhan (HHZ, heat-resistant) and IR36 (heat-susceptible) were subjected to high-temperature (HT, 40 °C) and normal-temperature (NT, 32 °C) treatments at the spikelet differentiation stage. HT treatment inhibited spikelet differentiation, aggravated spikelet degeneration, reduced spikelet size, and disordered carbohydrate allocation. Meanwhile, HT treatment increased nonstructural carbohydrate content in leaves, but decreased that in stems and young panicles, and the same tendencies of sucrose and starch contents were observed in leaves and stem. However, HT treatment significantly increased the sucrose content and sharply decreased the glucose and fructose contents in young panicles. Lower activity levels of soluble acid invertase (EC3.2.1.26) and sucrose synthase (EC2.4.1.13) were observed under HT treatment. Moreover, HT treatment reduced the activities of key enzymes associated with glycolysis and the tricarboxylic acid cycle, which indicated sucrose consumption was inhibited in young panicles under HT treatment. Exogenous glucose and fructose applied under HT treatment increased the spikelet number more than exogenous sucrose. In conclusion, the results demonstrated that the reduction of spikelet number under high temperature was more affected by the decrease in sugar consumption than the blocking of sucrose transport. The impairment of sucrose hydrolysis was the main reason for the inhibition of sugar utilization. Keywords: Rice, High temperature, Panicle development, Spikelet number, Carbohydrate allocation, Sugar consumption

In this study, durable superhydrophobic sponge with magnetic-responsive and fire-retarding was prepared. In the preparation process, polydopamine (PDA), layered double hydroxide (LDH), Fe3O4 nanoparticles and n-Octadecyl mercaptan (OM) acted as the “bio-glue”, fire retardant, magnetic materials and hydrophobic reagent, respectively. LDH and Fe3O4 nanoparticles were adhered on the skeleton surface of PU sponge via PDA to build micro/nano structure, and then the -NH2 of PDA could react with the -SH of OM (Michael addition reaction), which made the sponge repellent to water. The prepared sponge exhibited remarkable hydrophobicity (water contact angle = 163°)and highly oleophilic (oil contact angle = 0°). When used for absorbing oil and organics, the prepared sponge floated on the surface of oily wastewater, and it could be moved towards oil droplet under magnetic actuation. The as-prepared sponge could absorb various kinds of oils and organics up to 53.6 times of its own weight, and the absorbed oils could be collected through a simple squeezing process. The prepared sponge could be withstood at least 50 cycles of laundering without losing its magnetic properties and superhydrophobicity due to the viscidity of PDA and strong interaction between PDA and OM. In addition, it was difficult to ignite the prepared sponge in air after anchored LDH and Fe3O4 on the sponge skeleton surface. This might offer an environmentally friendly way to prepare “smart and safe” oil-recovery materials.

Superamphiphobic surfaces generally need a specific combination of low surface energy and re-entrant surface structure. Herein, we have created a hexane suspension of trichloro(1H,1H,2H,2H-tridecafluoro-n-octyl) silane, tetraethyl orthosilicate, silicon dioxide and titanium dioxide nanoparticles and modify a series of filter papers by one-step immersion in 10 min. Superhydrophobic and quasi-superoleophobic properties are obtained for the optimal filter papers, which repel both of polar and non-polar liquids such as water, glycerol, 1,4-butanediol, soybean oil and 1-octadecene with the contact angles of 168°, 158°, 154°, 145° and 121°, respectively. More importantly, the respective contribution of each component to the superhydrophobic and oleophobical property is explicated through a series of comparative experiments based on the optimal suspension prescription. The wettability transformation from quasi-superamphiphobicity to superhydrophilicity after UV irradiation is evaluated and illustrated. What’s more, the patterned paper is successfully used for the colorimetric detection of glucose using a simple paper-based analytical device. A linear correlation between gray intensity (GI) and glucose concentration (C), GI = − 10.7C + 161.8 is achieved with a correlation coefficient of 0.991, indicating the potential for semi-quantitative analysis of real sample in the field.

Silicon carbide (SiC) crystals were synthesized by microwave sintering using coal and tetraethoxysilane (TEOS) as raw materials. A sol-gel method was carried out to coat coal mineral particles with silicon dioxide (SiO2). The mixed raw powders were pre-formed by uniaxial pressing into cylindrical pellets in dimension of ~ 30 × 3 mm2. The pre-forming pressure was selected at 0 MPa, 1 MPa, 2 MPa, 3 MPa, 4 MPa and 5 MPa respectively, which led to different apparent density of the green pellets. The influence of apparent density of green pellets on microwave heating behavior was investigated. Different microwave thermal effects were analyzed. Techniques of XRD、SEM were carried out to characterize samples. It was found that pre-forming pressure showed crucial influences on microwave thermal effects and electric field (E-field) intensification. No SiC crystal could be formed without pre-forming pressure. Pre-forming pressure might be the prerequisite for synthesis of SiC by microwave heating. Five consecutive and indispensable heating stages including accumulation of residual air, microwave plasma generation, complex chemical reactions, nucleation and grain growth of SiC crystallites could be distinguished for samples under pre-forming pressure. Different pre-forming pressure leads to changes in heating behavior as well as morphologies of SiC crystals. ~ 4 MPa might be the optimized pre-forming pressure for both microwave plasma effects and E-field intensification.

In this paper, an excellent NH3-SCR activity CeZrTiAl catalyst with γ-Al2O3 nanosheets structure was prepared based on Ti-bearing BFS, which presented more than 90% NOx conversion between 260 and 440 °C. The good denitrification activity result from the γ-Al2O3 nanosheets acted as a framework, which makes active components disperse in an amorphous form and also induces a larger surface area. Meanwhile, the interaction between γ-Al2O3 nanosheets and CeO2 can lead to good reduction abilities and more acidic sites by increasing the content of Ce3+ and oxygen vacancies. The key to obtaining a highly active CeZrTiAl catalyst with nanosheets γ-Al2O3 is to convert Al into sulfate and then control the pH to form an important γ-AlOOH precursor. This established approach can be expanded to the controlled synthesis and stabilization of other Ti-bearing BFS catalysts with wide applications.

Polymerization-induced phase separation is comparatively applied to fabricating a superhydrophobic micro/nano surface by microwave and ultraviolet (UV) irradiation. The monolithic coatings can be tailored easily on different substrates with excellent chemical and mechanical stability in rigid conditions. Importantly, the patterned filter paper is successfully used for the colorimetric detection of nitrite handily.

Quinoline is a typical nitrogenous heterocyclic compound, which is carcinogenic, teratogenic, and mutagenic to organisms, and its wastewater is difficult to biodegrade directly. The bipolar electro-Fenton process was employed to treat quinoline solution. The process/reaction conditions were optimized through the single factor experiment. The degradation kinetics of chemical oxygen demand (COD) was analyzed. To get the degradation mechanism and pathways of quinoline, the intermediate products were identified by gas chromatograph&ndash, mass spectrometer (GC&ndash, MS). By using sodium chloride as supporting electrolyte in the electro-Fenton reaction system with initial pH 3.0, conductivity 15,800 &micro, s/cm, H2O2 concentration 71 mmol/L, current density 30.5 mA/cm2, and applied voltage 26.5 V, 75.56% of COD was decreased by indirect oxidation with electrogeneration of hydroxyl radicals (&bull, OH) and active chloric species in 20 min. The COD decrease of quinoline solution followed the first order reaction kinetic model. The main products of quinoline degradation were 2(1H)-quinolinone, 4-chloro-2(1H)-quinolinone, 5-chloro-8-hydroxyquinoline, and 5,7-dichloro-8-hydroxyquinoline. Furthermore, two possible degradation pathways of quinoline were proposed, supported with Natural charge distribution on quinoline and intermediates calculated at the theoretical level of MN15L/6-311G(d).

Polygonatum odoratum is widely used as a traditional food supplement and herbal medicine with strong antioxidant activity. However, systematic investigation of its antioxidants was limited. Ethanol extract of P. odoratum was fractioned on macroporous absorptive resin (D101) column. A bioassay-guided purification of flavonoid-rich fraction (IC50 value at 74.1 ± 11.9 μg/mL for DPPH scavenging) was realised via high-speed counter-current chromatography (HSCCC) using petroleum ether-ethyl acetate-methanol-water (2:3:3:2, v/v/v/v) as the solvent system combination with Sephadex LH-20 column chromatography (CC) eluting with MeCN-MeOH (1:1, v/v). Three novel homoisoflavonoids (1-3), along with eight homoisoflavonoids (4-11), were isolated. Their structures were elucidated by interpretating various spectroscopic data. All the isolated homoisoflavonoids showed potent antioxidant activities, while compounds 1, 4, and 6 with dihydroxylated B-rings exhibited stronger antioxidant activities (IC50 values at 3.8 ± 0.5, 4.9 ± 0.3 and 3.9 ± 0.4 μg/mL) than ascorbic acid (IC50 value at 5.3 ± 0.6 μg/mL).

A superhydrophobic marigold shape layered double hydroxide (LDH) film coated stainless steel mesh (SSM) was prepared by in-situ growth followed chemical modification in this work. The obtained SSM exhibited excellent superhydrophobicity, self-cleaning ability, physical and chemical durability, indicating the superior ability of adapting to outdoor environment. In addition, the obtained SSM also exhibited excellent corrosion resistance and the efficiency reached up to 97.3%. As for application evaluation, the obtained SSM could be applied in continuous oil-water separation with a high efficiency and flux after 50 times reuse (98.5% and 1800 L m−2 h−1 for chloroform-water mixture). More importantly, the obtained SSM exhibited a high intrusion pressure (5.39 kPa), which was helpful to the rapid separation of oil-water mixture. Consequently, the obtained superhydrophobic SSM offered a promise in solving practical application problems of oil-water separation in outdoor and thereby showed great potential in large-scale industrial applications.

AIE and ACQ chromophores with exactly opposite photoluminescence behaviours are integrated in mesostructured organosilicas for multicolour emission including high-quality white light., Aggregation-induced emission (AIE) and aggregation-caused quenching (ACQ) materials are important for various fluorescence-based applications but cannot easily collaborate because of their opposite luminescence behaviours. Here, we demonstrate a strategy to integrate AIE and ACQ chromophores in periodic mesoporous organosilicas (PMOs) for high-efficiency multicolour emission. Tetraphenylethene (TPE)-bridged AIE-PMOs are prepared as hosts to encapsulate ACQ dyes (e.g. RhB), which enables fine-tuning of ACQ@AIE-PMO emissions over the entire visible spectrum in the solid and film states. Significantly, high-quality white light is achieved with CIE coordinates of (0.32, 0.33) and a quantum yield of up to 49.6%. Because of their high stability and solution processability, the ACQ@AIE-PMOs can be applied in solid-state lighting and bioimaging. This design concept opens up new perspectives for developing high-performance luminescent materials by the combination of a wide variety of AIE and ACQ chromophores.

A field plot experiment was conducted to study effect of organic fertilizers on yield and quality of rice grains and nitrogen use efficiency.The results showed that,the rice yield is much higher under the facility treatments of 20% pig manure and 10% pig manure decomposed organic fertilizer and 20% biogas fertilizer instead of pure fertilizer treatments.Compared with CK treatments the rice yield respectively increased by 103.49%,81.62% and 74.64% under the three treatments and increased by 38.67%,23.77% and 19.02% than that of the pure fertilizer treatments.The 20% pig manure decomposed organic fertilizer instead of 20% nitrogen fertilizer had the highest nitrogen use efficiency of 32.64% which was 2.66% higher than pure chemical fertilizer.And both that of 20% pig manure and 10% pig manure decomposed organic fertilizer were higher compared to the pure fertilizer treatments with the growth of 1.12% and 1.04%.According to the results,we organic fertilizer can increase the rice yield and nitrogen fertilizer use efficiency.Furthermore,compared with pure fertilizer treatment,replacing the same proportion of chemical fertilizer by either 10% of the straw,or 20% of the pig manure,or 30% of the pig manure organic fertilizer or 20% biogas could lower chalk whiteneww.And replacement of the same proportion of chemical nitrogen fertilizer by either 20% of pig manure or 20%,or 10% or 30% of pig manure decomposed fertilizer could improve the rice gel consistency,10% of the straw instead of 10% chemical fertilizer treatment had a lower amylase content.In conclusion,organic fertilizers could improve the appearance quality of rice and cooking quality.

Using on Luliangyou996 as provided material, choosing middling fertility field for experiment, setting up 5 treatment levels, which are: fertilizer model without N, farmers-familiar fertilizer model(150 kg/hm2,according to N), the optimal-nutrient management model(120 kg/hm2), super-high-yield and high-efficient model(150 kg/hm2), super- high-yield model(180 kg/hm2), various forms of nitrogen nutrition on agronomic characters and nitrogen use efficiency on early rice were studied. The results showed that: super high yield and high efficient model could promote root growth, increase chlorophyll content of leaves, enhance the formation and accumulation of photosynthetic products, enhance the nutrient absorptivity of rice, compared to the farmers familiar fertilizer models which are treated at the same nitrogen fertilization level, its yield increased 5.61%, nitrogen use efficiency increased by 9.06 percentage points, relativly increased 34.49%. It showed that super high yield and high efficient model can improve the yield of rice,can be expected to effectively improve the nitrogen utilization, reduce nitrogen losses, decrease the pollution caused by fertilizer application.

中药活性成分的快速分离分析一直是中药研究的重点和热点问题。该文建立了在线亲和固相萃取-高效液相色谱-二极管阵列检测-四极杆飞行时间质谱技术快速筛选中药中与 α -葡萄糖苷酶有结合作用的活性成分的方法。四通阀和六通进样阀组成接口界面，收集亲和固相萃取柱中与 α -葡萄糖苷酶有结合作用的活性成分，接着进入液相色谱系统进行分析鉴定。阳性对照品（（+）-儿茶素）和阴性对照品（水杨酸）混合物筛选确定了方法的特异性和准确性。接着，以玉竹为研究对象，筛选出9种主要的 α -葡萄糖苷酶抑制活性化合物，包括5种苯乙基肉桂酰胺类化合物，4种双氢高异黄酮类化合物。结果表明建立的方法简便、快速、特异性强，可用于任何复杂体系中 α -葡萄糖苷酶结合活性成分的筛选。