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Seed-induced synthesis of functional MFI zeolite materials: Method development, crystallization mechanisms

Zhaoqi Ye, Hongbin Zhang, Yahong Zhang, Yi Tang

《化学科学与工程前沿(英文)》 2020年 第14卷 第2期   页码 143-158 doi: 10.1007/s11705-019-1852-x

摘要: As an important zeolite material, MFI zeolites, as well as their controllable synthesis, are of great interest in both basic and applied science. Among the developed synthetic approaches, the seed-induced method has gradually evolved into a facile, low-cost, and even green alternative to give zeolites the desirable physicochemical properties. In this review, we briefly summarize the development of seed-induced syntheses of diverse functional MFI zeolites, where the “living” seed crystals not only direct the formation of zeolitic framework but also function as special “templates” or “units” to fine-tune the zeolite materials with diverse sizes, shapes, compositions, morphologies and pore structures. Moreover, on the basis of their structural features and crystallization behaviors in seed-induced synthesis, we reveal the roles of seeds and discuss the related crystallization mechanisms including both classical and non-classical pathways. We also want to guide readers to investigate the structure-performance relationships between these functional MFI zeolite catalysts and suitable catalytic reactions.

关键词: seed-induced synthesis     MFI zeolite     synthesis mechanism     catalytic property    

Novel seed-assisted synthesis of indium tin oxide submicro-cubes and their resistivity

《化学科学与工程前沿(英文)》 2023年 第17卷 第5期   页码 557-569 doi: 10.1007/s11705-022-2249-9

摘要: Indium tin oxide films, an important n-type semiconductor oxide, show great prospects in optoelectronic device applications. Consequently, as a key raw material of targets for sputtering films, it is important to prepare low-resistivity indium tin oxide powders. Herein, low-resistivity indium tin oxide submicro-cubes are synthesized by a seed-assisted coprecipitation method. The effects of seed content, In3+ concentration, aging time, reaction temperature and calcination temperature on resistivity were investigated by single factor and orthogonal experiments. To ensure reliability and reproducibility of data, each experiment was repeated three times and resistivity of each sample was measured three times to obtain average value. The results indicated that optimal sample was matched with cubic phase In2O3. The single-crystal indium tin oxide particles exhibited a regular cubic shape with a size of nearly 500 nm and low resistivity of 0.814 Ω·cm. Compared with particles prepared by the conventional coprecipitation method, indium tin oxide submicro-cubes showed good dispersion. The presence of seed particles provided nucleation sites with lower energy barriers and promoted formation of submicro-cubes. The face-to-face contact among particles and good dispersion contributed to electron transfer, resulting in lower resistivity. The seed-assisted synthesis provides a novel way to prepare low-resistivity indium tin oxide submicro-cubes.

关键词: indium tin oxide     submicro-cubes     resistivity     seed-assisted coprecipitation method     orthogonal experiment    

Synthesis and ultraviolet/aggregation-induced emission investigation of novel tetraphenylvinyl hydrazone

《化学科学与工程前沿(英文)》 2023年 第17卷 第12期   页码 2061-2073 doi: 10.1007/s11705-023-2366-0

摘要: Herein, three novel tetraphenylethylene hydrazone chemosensors TC12, SC16, and TC16 are prepared for the selective detection of F. Two NH and one C=N units are incorporated into the sensors for better colorimetric responses, whereas the tetraphenyl unit is in charge of the aggregation-induced emission effect. Among them, compounds SC16 and TC16 form stable gels with some organic solvents. All the tetrahydrofuran/H2O solutions of the three compounds exhibit aggregation-induced emission effect, whereby the fluorescence emission increases by varying degrees with the volume of poor solvent water. Moreover, good aggregation-induced emission effects are observed in the self-assembly of SC16 and TC16. As a sample chemosensor, TC12 in tetrahydrofuran responds to F selectively with high sensitivity, with the colorimetric and fluorometric detection limits of 8.25 × 10−7 mol·L–1 and 2.69 × 10−7 mol·L–1, respectively. The reversible gel-sol-gel phase transition and color changes indicate that both SC16-dimethyl sulfoxide and TC16-ethyl acetate gels specifically respond to F with good sensitivity. The detection results are well supported by ultraviolet-visible spectroscopy, fluorescent spectroscopy, and 1H nuclear magnetic resonance. More importantly, the driving forces of gelation are visually clarified through the single crystal X-ray analysis of compound TOMe.

关键词: organogelator     tetraphenylvinyldrazone     single crystal     aggregation-induced emission effect     ion sensing    

Influence of harvest date on seed yield and quality in forage kochia

Cody F. CREECH, Blair L. WALDRON, Corey V. RAMSOM, Dale R. ZOBELL, Joseph Earl CREECH

《农业科学与工程前沿(英文)》 2018年 第5卷 第1期   页码 71-79 doi: 10.15302/J-FASE-2017196

摘要: Forage kochia ( ) is used for rangeland reclamation and livestock and wildlife forage, but limited research has been conducted on its seed production. Therefore, this research evaluated the effect of harvest date on seed weight, germination, and seed yield of forage kochia subspecies and . Seed was harvested from individual plants for 3 years during October, November, and December. October harvest had the lightest 100-seed weights, with the November harvest slightly heavier than December, for most accessions. Cultivar Snowstorm and breeding line Sahsel, both subsp. , had the greatest 100-seed weights in November, 155 and 143 mg, respectively, whereas, cv. Immigrant (subsp. ), the standard for forage kochia, ranked among the least for 100-seed weight. For most accessions, germination was lowest from the October harvest (11%–43%), with greater germination with November and December harvested seeds (43%–64%). Viable seed yields were greatest in November with the exception of two accessions, which peaked in October, indicating earlier maturity. Results indicate that forage kochia usually reaches optimum seed maturity by early November, after plants are exposed to freezing temperatures; however, earlier maturing accessions exist in both subspecies and .

关键词: forage     rangeland     seed germination     seed quality    

洞察无有机模板合成沸石分子筛催化材料

王叶青,吴勤明,孟祥举,肖丰收

《工程(英文)》 2017年 第3卷 第4期   页码 567-574 doi: 10.1016/J.ENG.2017.03.029

摘要:

作为当前最重要的工业催化材料之一,沸石分子筛的合成一般是在有机模板存在的条件下水热合成的,但是该合成过程会产生大量的有害气体和废水,不仅污染环境,还增加了生产成本。本文旨在概述有机模板在沸石分子筛合成过程中的角色,并据此分别设计沸石晶种和导向剂溶液导向的无有机模板条件下合成沸石分子筛的路线。在此基础上,总结并揭示了在无有机模板的Na+ 体系中合成的沸石分子筛的微孔体积与Si/Al 比值的关系,即微孔体积越大,Si/Al 比值越小,这对于无有机模板条件下合成Si/Al 比值可调控的沸石分子筛和设计它们的合成路线具有重要意义。

关键词: 无有机模板合成     沸石分子筛     沸石晶种     沸石导向剂溶液     Si/Al 比值    

Effects of seed particles Al

Xiao Zhang, Biwu Chu, Junhua Li, Chaozhi Zhang

《环境科学与工程前沿(英文)》 2017年 第11卷 第4期 doi: 10.1007/s11783-017-0936-4

摘要: Seed particles Al O , Al (SO ) and H SO were selected to investigate their effects on secondary aerosol (SA) formation in toluene/NO photooxidation under sulfur dioxide (SO ) and ammonia (NH ). Effect of seed particles on SA formation was related to their acid-base properties and the presence of acid or alkaline gases. Under NH -poor condition, SA formation increased with increasing SO concentration due to the acid-catalyzing effect of the oxidation products of SO (i.e. H SO ). The enhancing effect of SO became unobvious under NH -rich condition, because NH would eliminate the acid-catalyzing effect by neutralizing the acid products. Acidic seeds H SO accelerated SA formation under either SO or NH condition. Weak acidic Al (SO ) seeds didn’t affect obviously on SA formation. The inhibiting effect of amphoteric seeds Al O on SA formation was related to the presence of SO / NH due to their acid-base property. Under NH -poor condition, the inhibiting effect of Al O on SA formation decreased with increasing concentration of SO , while under NH -rich condition, the inhibiting effect wasn’t remarkable.

关键词: Seed particle     Secondary aerosol     Sulfur dioxide     Ammonia     Acid-catalyzing effect    

Multiple effects of grape seed polyphenolics to prevent metabolic diseases

Torey ARVIK, Hyunsook KIM, James SEIBER, Wallace YOKOYAMA

《农业科学与工程前沿(英文)》 2018年 第5卷 第3期   页码 351-361 doi: 10.15302/J-FASE-2018235

摘要:

Obesity is increasing in developing countries. Population studies show a relationship between affluence and obesity. Changing food intake patterns with affluence such as preference for foods with less astringent polyphenolic compounds and dietary fibers may increase risk of metabolic dysfunctions due to caloric imbalance. Animal models of obesity consistently show that grape seed procyanidins prevent increases in body and abdo- minal adipose weight gain, plasma cholesterol, liver weight gain and inflammation in animals on high fat diets. The mechanisms are not clear because the oral intake of procyanidins results in pleiotropic interactions with proteins in the mouth, stomach, small intestine, cecum and colon that affect the rate of digestion of bioavailability of macronutrients, sterols, and dietary fiber. Procyanidins also bind bile acids and reduce intestinal permeability to inflammatory bacterial cell wall fragment. Procyanidins are not degraded or metabolized until reaching the lower gut where they can be metabolized into phenolic acids by gut bacteria. While they are metabolized by gut bacteria, they also alter total numbers and distribution of phyla and species of gut bacteria. Gut bacteria are recognized as significant contributors to obesity and obesity related metabolic diseases. The review examines the different pleiotropic effects of grape seed procyanidins that have a significant effect on metabolic disease in animal models of obesity.

关键词: grape seed     obesity     procyanidins     high fat     microbiota     animal models    

Factors affecting the formation of zeolite seed layers and the effects of seed layers on the growth of

ZHANG Xiongfu, WANG Jinqu, LIU Hai′ou, WANG Anjie

《化学科学与工程前沿(英文)》 2007年 第1卷 第2期   页码 172-177 doi: 10.1007/s11705-007-0032-6

摘要: The present study investigates the formation of silicalite-1 seed layers on a porous carbon support of 0.5 μm pore size and α-A1O supports with different pore sizes (0.1 μm and 4 μm) via the slip-casting technique. The effects of support property, seed size and solvent on the formation of seed layers were investigated in detail. The growth of silicalite-1 membranes on different seeded supports by hydrothermal synthesis was also evaluated. The scanning electron microscopy (SEM) and X-ray diffraction (XRD) characterizations indicate that a continuous seed layer can be obtained on the smooth support of 0.1 μm pore size by using any seed of 100 nm, 600 nm or 2.2 μm in size, whereas, on the coarse supports with either 0.5 μm or 4 μm pore size, a continuous seed layer cannot be formed using the above seed sizes and the same seeding time. At a longer contact time, a seed layer can also be formed using 100 nm seed on the supports with larger pore size. However, the layer is not uniform and smooth. For a hydrophobic porous carbon support, seeding ethanol suspension, which has weak polarity, favors the formation of a continuous seed layer. The seed layers and membranes grown from the smaller seed are more uniform and continuous and possess smoother surfaces than those from the larger seed. The seed layer and respective grown membrane formed from nanosized seed (100 nm) are the most uniform and compact. With this method of seeded secondary synthesis of zeolite membranes, the quality of a membrane mainly depends on the quality of the seed layer.

关键词: silicalite-1     α-A1O     growth     seeding ethanol     quality    

Molecular regulation and genetic improvement of seed oil content in

Wei HUA,Jing LIU,Hanzhong WANG

《农业科学与工程前沿(英文)》 2016年 第3卷 第3期   页码 186-194 doi: 10.15302/J-FASE-2016107

摘要: As an important oil crop and a potential bioenergy crop, L. is becoming a model plant for basic research on seed lipid biosynthesis as well as seed oil content, which has always been the key breeding objective. In this review, we present current progress in understanding of the regulation of oil content in , including genetics, biosynthesis pathway, transcriptional regulation, maternal effects and QTL analysis. Furthermore, the history of breeding for high oil content in is summarized and the progress in breeding ultra-high oil content lines is described. Finally, prospects for breeding high oil content cultivars are outlined.

关键词: breeding     maternal effects     oilseed rape     QTL    

Effects of irrigation and nitrogen management on hybrid maize seed production in north-west China

Hui RAN,Shaozhong KANG,Fusheng LI,Ling TONG,Taisheng DU

《农业科学与工程前沿(英文)》 2016年 第3卷 第1期   页码 55-64 doi: 10.15302/J-FASE-2016091

摘要: Scientific irrigation and nitrogen management is important for agricultural production in arid areas. To quantify the effect of water and nitrogen management on yield components, biomass partitioning and harvest index ( ) of maize for seed production with plastic film-mulching, field experiments including different irrigation and N treatments were conducted in arid north-west China in 2013 and 2014. The results indicated that kernel number per plant ( ) was significantly affected by irrigation and N treatments. However, 100-kernel weight was relatively stable. Reducing irrigation quantity significantly increased stem partitioning index ( ) and leaf partitioning index ( ), and decreased ear partitioning index ( ) at harvest, but lowering N rate (from 500 to 100 kg N·hm ) did not significantly reduce , , and at harvest. was significantly reduced by reducing irrigation quantity, but not by reducing N rate. Linear relationships were found between , , , at harvest and and evapotranspiration ( ).

关键词: yield components     biomass partitioning     harvest index     irrigation     nitrogen     maize for seed production    

Treatment of swine wastewater in aerobic granular reactors: comparison of different seed granules as

Lin LIU,Qiyu YOU,Valerie GIBSON,Xu HUANG,Shaohua CHEN,Zhilong YE,Chaoxiang LIU

《环境科学与工程前沿(英文)》 2015年 第9卷 第6期   页码 1139-1148 doi: 10.1007/s11783-015-0823-9

摘要: The granulation process, physic-chemical properties, pollution removal ability and bacterial communities of aerobic granules with different feed-wastewater (synthetic wastewater, R1; swine wastewater, R2), and the change trend of some parameters of two types of granules in long-term operated reactors treating swine wastewater were investigated in this experiment. The result indicated that aerobic granulation with the synthetic wastewater had a faster rate compared with swine wastewater and that full granulation in R1 and R2 was reached on the 30th day and 39th day, respectively. However, although the feed wastewater also had an obvious effect on the biomass fraction and extracellular polymeric substances of the aerobic granules during the granulation process, these properties remained at a similar level after long-term operation. Moreover, a similar increasing trend could also be observed in terms of the nitrogen removal efficiencies of the aerobic granules in both reactors, and the average specific removal rates of the organics and ammonia nitrogen at the steady-state stage were 35.33 mg·g VSS and 51.46 mg·g VSS for R1, and 35.47 mg·g VSS and 51.72 mg·g VSS for R2, respectively. In addition, a shift in the bacterial diversity occurred in the granulation process, whereas bacterial communities in the aerobic granular reactor were not affected by the seed granules after long-term operation.

关键词: aerobic granules     livestock wastewater     sequencing batch reactor     biological wastewater treatment     bacterial community    

Synthesis, spectroscopic, and electrochemical properties of two dyads consisted of tetrathiafulvalene

Guoqiao LAI, Yibo LIU, Meijiang LI, Yongjia SHEN

《化学科学与工程前沿(英文)》 2009年 第3卷 第2期   页码 192-195 doi: 10.1007/s11705-009-0015-x

摘要: Two donor-σ-acceptor molecules containing tetrathiafulvalene (TTF) and carbazole moieties were synthesized by the reaction of 9-(4-bromo-butyl)-carbazole ( ) with 2,6-bis(hexylthio)-3-(2-cyanoethylthio)-7-(methylthio)-tetrathiafulvalene ( ) or 2,6-bis(2-cyanoethylthio)-3,7-bis(methylthio)tetrathiafulvalene ( ) in the presence of CsOH·H O, respectively. The structures of the molecules were characterized by H NMR, C NMR, MS, and elemental analyses. They showed negligible intramolecular charge-transfer interaction in their ground states as indicated by their UV-Vis spectroscopics and cyclic voltammetry results. Compared with carbazole, their fluorescence was strongly quenched, which implied that a photo induced electron transfer (PET) interaction between TTF and carbazole moieties occurred.

关键词: donor-σ-acceptor molecule     intramolecular charge transfer interaction     photo induced electron transfer     tetrathiafulvalene     carbazole    

全球作物种业发展概况及对我国种业发展的战略思考

郑怀国,赵静娟,秦晓婧,贾倩,齐世杰

《中国工程科学》 2021年 第23卷 第4期   页码 45-55 doi: 10.15302/J-SSCAE-2021.04.022

摘要:

种业是农业的“芯片”,是国家战略性、基础性核心产业。随着国家“解决好种子和耕地问题”“有序推进生物育种产业化”“开展种源‘卡脖子’技术攻关”等指导性意见的出台和重点任务的部署,种业已成为推动我国农业跨越式发展的重要引擎。本文从种质资源保护与利用、生物育种技术发展、种子产业发展等方面概述了全球作物种业的发展现状,基于国际视角深入分析了我国种业存在的问题;在此基础上,从实施国家种质资源战略、夯实种业发展基础,实施种业科技创新战略、实现原始性创新的突破,全面构建中国特色种业体系、提升产业竞争力,实施种业强企战略、强化企业创新主体地位,推进监管制度现代化、确保技术优势转化为产业优势等方面总结了对我国作物种业发展的启示。相关研究对于全面了解全球作物种业发展概况,及时发现并解决我国种业存在的问题,进而制定我国种业发展战略,推进我国生物育种关键技术突破,前瞻性规划种业的产业布局具有参考意义。

关键词: 国际种业,作物种业,种质资源,生物育种技术    

Response of peroxidase and catalase to acid rain stress during seed germination of rice, wheat, and rape

WANG Lihong, HUANG Xiaohua, ZHOU Qing

《环境科学与工程前沿(英文)》 2008年 第2卷 第3期   页码 364-369 doi: 10.1007/s11783-008-0053-5

摘要: Seed germination of plants with various acid-resistance display different responses to acid rain. To understand the reason why such differences occur, the effects of simulated acid rain (pH 2.5–5.0) on the activities of peroxidase (POD) and catalase (CAT) during seed germination of rice (), wheat (), and rape ( var. ) were investigated. Results indicated that the maximum change in activities of CAT and POD by acid rain treatment with different acidity and time in relation to the referent treatment without acid rain, was in the order: rice (28.8%, 31.7%) < wheat (34.7%, 48.3%) < rape (79.3%, 50.0%). The pH level for which the treatment with acid rain did not cause significant difference ( < 0.05) was in the order: rice (3.5) > wheat (4.0) > rape (5.0). Moreover, the change in activity of POD was higher than that of CAT, which showed that POD was more sensitive to acid rain stress than CAT. The difference in the ability of POD and CAT in removing free radicals was one reason why the germination indexes of these three species behaved differently.

Comparison of prechilling stratification and sulfuric acid scarification on seed germination of

Nan WANG, Jing GAO, Suiqi ZHANG, Feng YAN

《农业科学与工程前沿(英文)》 2017年 第4卷 第2期   页码 220-227 doi: 10.15302/J-FASE-2017146

摘要: In semi-arid regions of the Loess Plateau, water deficiency restricts plant performance. (switchgrass), which is a highly versatile grass, had been introduced to the Plateau as a restoration species. To determine if prechilling stratification (PCS) and sulfuric acid scarification (SAS) can optimize establishment, cvs Pathfinder, Trailblazer and Alamo were tested under different ambient water potentials by measuring germination and root and shoot growth along water potential gradients under laboratory conditions. Both PCS and SAS improved total germination percentage (TGP), with PCS being more beneficial. The effect of PCS and SAS on mean germination time (MGT) weakened gradually with increasing drought stress. Both PCS and SAS showed no obvious effect on promoting root and shoot growth. Both PCS and SAS reduced base water potential requirement for reaching 50% germination of Pathfinder and Trailblazer, with this effect greater for PCS. These results indicate that embryo dormancy may be a major factor limiting germination of under drought conditions. Pathfinder appears to be more suitable for a semi-arid environment, whereas Alamo appears to be unsuitable for drought conditions. Given the large difference between predicted value and measured value, the reliability and applicable scope of linear regression estimated Y needs further investigation, specification and optimization.

关键词: base water potential     data analysis method     embryo growth     germination    

标题 作者 时间 类型 操作

Seed-induced synthesis of functional MFI zeolite materials: Method development, crystallization mechanisms

Zhaoqi Ye, Hongbin Zhang, Yahong Zhang, Yi Tang

期刊论文

Novel seed-assisted synthesis of indium tin oxide submicro-cubes and their resistivity

期刊论文

Synthesis and ultraviolet/aggregation-induced emission investigation of novel tetraphenylvinyl hydrazone

期刊论文

Influence of harvest date on seed yield and quality in forage kochia

Cody F. CREECH, Blair L. WALDRON, Corey V. RAMSOM, Dale R. ZOBELL, Joseph Earl CREECH

期刊论文

洞察无有机模板合成沸石分子筛催化材料

王叶青,吴勤明,孟祥举,肖丰收

期刊论文

Effects of seed particles Al

Xiao Zhang, Biwu Chu, Junhua Li, Chaozhi Zhang

期刊论文

Multiple effects of grape seed polyphenolics to prevent metabolic diseases

Torey ARVIK, Hyunsook KIM, James SEIBER, Wallace YOKOYAMA

期刊论文

Factors affecting the formation of zeolite seed layers and the effects of seed layers on the growth of

ZHANG Xiongfu, WANG Jinqu, LIU Hai′ou, WANG Anjie

期刊论文

Molecular regulation and genetic improvement of seed oil content in

Wei HUA,Jing LIU,Hanzhong WANG

期刊论文

Effects of irrigation and nitrogen management on hybrid maize seed production in north-west China

Hui RAN,Shaozhong KANG,Fusheng LI,Ling TONG,Taisheng DU

期刊论文

Treatment of swine wastewater in aerobic granular reactors: comparison of different seed granules as

Lin LIU,Qiyu YOU,Valerie GIBSON,Xu HUANG,Shaohua CHEN,Zhilong YE,Chaoxiang LIU

期刊论文

Synthesis, spectroscopic, and electrochemical properties of two dyads consisted of tetrathiafulvalene

Guoqiao LAI, Yibo LIU, Meijiang LI, Yongjia SHEN

期刊论文

全球作物种业发展概况及对我国种业发展的战略思考

郑怀国,赵静娟,秦晓婧,贾倩,齐世杰

期刊论文

Response of peroxidase and catalase to acid rain stress during seed germination of rice, wheat, and rape

WANG Lihong, HUANG Xiaohua, ZHOU Qing

期刊论文

Comparison of prechilling stratification and sulfuric acid scarification on seed germination of

Nan WANG, Jing GAO, Suiqi ZHANG, Feng YAN

期刊论文