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The structure-directing role of heterologous seeds in the synthesis of zeolite 被引量:2
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作者 Haoyang Zhang Binyu Wang Wenfu Yan 《Green Energy & Environment》 SCIE EI CAS CSCD 2024年第5期792-801,共10页
Zeolites have been widely used as catalysts,ion-exchangers,and adsorbents in chemical industries,detergent industry,steel industry,glass industry,ceramic industry,medical and healthfield,and environmentalfield,and recen... Zeolites have been widely used as catalysts,ion-exchangers,and adsorbents in chemical industries,detergent industry,steel industry,glass industry,ceramic industry,medical and healthfield,and environmentalfield,and recently applied in energy storage.Seed-assisted synthesis is a very effective approach in promoting the crystallization of zeolites.In some cases,the target zeolite cannot be formed in the absence of seed zeolite.In homologous seed-assisted synthesis,the structure of the seed zeolite is the same to that of the target zeolite,while the structure of the seed zeolite is different to that of the target zeolite in the heterologous seed-assisted synthesis.In this review,we briefly summarized the heterologous seed-assisted syntheses of zeolites and analyzed the structure-directing effect of heterologous seeds and surveyed the“common composite building units(CBUs)hypothesis”and the“common secondary building units(SBUs)hypothesis”.However,both hypotheses cannot explain all observations on the heterologous seed-assisted syntheses.Finally,we proposed that the formation of the target zeolite does need nuclei with the structure of target zeolite and the formation of the nuclei of the target zeolite can be promoted by either the undissolved seed crystals with the same CBUs or SBUs to the target zeolite or by the facilitated appropriate distribution of the specific building units due to the presence of the heterologous seed that does not have any common CBUs and SBUs with the target zeolite. 展开更多
关键词 ZEOLITE Heterologous seed SYNTHESIS Structure-directing effect
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Detailed Analyses of Nymphea Seeds Consumed in the Senegal River Valley
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作者 Nicolas Cyrille Ayessou Michel Bakar Diop +2 位作者 Fatou Kiné Gueye César Bassène Mame Samba Mbaye 《Food and Nutrition Sciences》 CAS 2024年第8期695-700,共6页
Physicochemical investigations were performed on seeds of Nymphea lotus and N. micrantha consumed in the Senegal River valley. They revealed a composition similar to that of cereals. In order to estimate their intrins... Physicochemical investigations were performed on seeds of Nymphea lotus and N. micrantha consumed in the Senegal River valley. They revealed a composition similar to that of cereals. In order to estimate their intrinsic quality, the determination of their amino acid, fatty acid and monosaccharids profiles was done. The results indicate that monosaccharides are represented specifically by saccharose (7%) and glucose (0.67%);a predominance of stearic acid and linoleic acid as unsaturated acids (24.86%);arachidic and palmitic acids as the only saturated acid found (11.12%);a good ratio of unsaturated/saturated acid (2.23);a lack of oleic acid, linoleic, palmitoleic, myristic, caprylic acids;a poor-quality index protein due to low quantity amino acids. Nevertheless, all essential amino acids are present in the seeds. The Nymphea sp grains consumed by the populations around the Senegal River valley offer an interesting nutritional quality linked to fatty acids and carbohydrates. 展开更多
关键词 Nymphea seeds COMPOSITION
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Dormancy of Amaranthus retroflexus L. Seeds and Physiological Response Seedlings to Acifluorfen Sodium
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作者 Ding Wei Liu Junliang +1 位作者 Cheng Zhuo Cheng Peng 《Journal of Northeast Agricultural University(English Edition)》 CAS 2024年第1期1-10,共10页
Amaranthus retroflexus L. is a serious and widespread malignant weed in soybean fields in Heilongjiang Province. Exploring the dormancy characteristics of A. retroflexus L. seeds and the physiological response of its ... Amaranthus retroflexus L. is a serious and widespread malignant weed in soybean fields in Heilongjiang Province. Exploring the dormancy characteristics of A. retroflexus L. seeds and the physiological response of its seedlings to acifluorfen sodium can provide a basis for further researches on its resistance mechanism. Using newly harvested and stored A. retroflexus L. seeds for one year as experimental materials, the effects of different concentrations of HCl, NaOH, water temperature, gibberellic acid(GA) and polyethylene glycol(PEG) on the dormancy and germination of A. retroflexus L. seeds were studied. The sensitivity of A. retroflexus L.to acifluorfen sodium was determined using bioassay. The effects on leaf chlorophyll content and target enzyme activity were studied at a normal dosage of 360 g a.i. hm^(-2) and a doubling dosage of 720 g a.i. hm^(-2) of acifluorfen sodium. Newly harvested seeds exhibiting dormancy were soaked in water of various temperatures and in different concentrations of NaOH and HCl, which were ineffective in breaking the seed dormancy. GA could break seed dormancy, and the highest seed germination rate reached 93.33% when they were soaked at 3 000 mg·L^(-1) for 72 h and 4 000 mg·L^(-1) for 48 h. The drought stress was simulated with a 15%-25% polyethylene glycol solution, which had no significant effect on the seed germination rate. The GR_(50) value of acifluorfen sodium for A. retroflexus L. was 705.7 g a.i. hm^(-2), which was 1.96 times the recommended dose in the field. After the application of different doses of acifluorfen sodium, the chlorophyll content of A. retroflexus L. reached its minimum value 3 days after treatment(DAT), and then gradually increased. The activity of the target enzyme protoporphyrinogen oxidase(PPO) reached the highest value at 7 DAT under different dosages, and gradually returned to normal levels thereafter. Soaking with gibberellin was an effective method to break seed dormancy. A. retroflexus L. seeds had certain drought resistance during the germination process. A. retroflexus L. was not sensitive to acifluorfen sodium and acifluorfen sodium ether, and could not effectively inhibit the PPO activity, indicating that A. retroflexus L. had target resistance to acifluorfen sodium. 展开更多
关键词 Amaranthus retroflexus L.seed seed dormancy acifluorfen sodium target resistance
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EMS-Mediated Mutagenesis in Marigold Seeds and Its Effects on Seedling Growth and Physiology
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作者 Chao Meng Ikram Ullah +8 位作者 Wenjin Wu Yiping Zhang Ruixue Shi Shaodan Luo Cuixia Luo Satyabrata Nanda Mahmoud FSeleiman Yalian Jiang Wangqi Huang 《Phyton-International Journal of Experimental Botany》 SCIE 2024年第11期3029-3038,共10页
Marigolds(Tagetes spp.)are popular horticultural plants worldwide.The current study aimed to investigate the optimal mutagenic conditions for marigold seeds using EMS(ethyl methanesulfonate)mutagenesis.Different con-c... Marigolds(Tagetes spp.)are popular horticultural plants worldwide.The current study aimed to investigate the optimal mutagenic conditions for marigold seeds using EMS(ethyl methanesulfonate)mutagenesis.Different con-centrations and treatment times of EMS were applied to investigate their effects on the marigold seed germination rate,growth traits,antioxidant enzyme activities(i.e.,SOD and POD),and malondialdehyde(MDA)contents.Results indicated that with increasing the EMS treatment duration and concentration,the seed germination rate and growth treatments were reduced,accompanied by elevated MDA content.In addition,SOD and POD activ-ities initially correlated positively with the growth tratis at the lowest concentrations and shortest durations of EMS,but such relationship diminished beyond certain thresholds.The comprehensive analysis identified the opti-mal mutagenic conditions as 1%EMS treatment for 12 h,achieving a semi-lethal dose and enhancing stress-resis-tant components in seedlings.Thesefindings are pivotal for advancing genetic enhancement and germplasm innovation in marigolds. 展开更多
关键词 Marigolds seed germination EMS mutagenesis genetic enhancement
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Highly ordered crystallization of α-FAPbl_(3) films via homogeneous seeds for efficient perovskite solar cells
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作者 Guohui Luo Linfeng Zhang +11 位作者 Liyun Guo Xiuhong Geng Penghui Ren Yi Zhang Haihua Hu Xiaoping Wu Lingbo Xu Ping Lin Haiyan He Xuegong Yu Peng Wang Can Cui 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第7期625-634,共10页
Formamidine lead triiodide(FAPbI_(3))perovskites have become the most promising photovoltaic materials for perovskite solar cells with record power conversion efficiency(PCE).However,random nucleation,phase transition... Formamidine lead triiodide(FAPbI_(3))perovskites have become the most promising photovoltaic materials for perovskite solar cells with record power conversion efficiency(PCE).However,random nucleation,phase transition,and lattice defects are still the key challenges limiting the quality of FAPbI_(3) films.Previous studies show that the introduction or adding of seeds in the precursor is effective to promote the nucleation and crystallization of perovskite films.Nevertheless,the seed-assisted approach focuses on heterogeneous seeds or hetero-composites,which inevitably induce a lattice-mismatch,the genera-tion of strain or defects,and the phase segregation in the perovskite films.Herein,we first demonstrate that high-quality perovskite films are controllably prepared using α-and δ-phases mixed FAPbI_(3) micro-crystal as the homogeneous seeds with the one-step antisolvent method.The partially dissolved seeds with suitable sizes improve the crystallinity of the perovskite flm with preferable orientation,improved carrier lifetime,and increased carrier mobility.More importantly,the α-phase-containing seeds promote the formation of α-phase FAPbI_(3) films,leading to the reduction of residual lattice strain and the suppres-sion of I-ion migration.Besides,the adding of dimethyl 2,6-pyridine dicarboxylate(DPD)into the pre-cursor further suppresses the generation of defects,contributing to the PCE of devices prepared in air ambient being significantly improved to 23.75%,among the highest PCEs for fully air-processed FAPbI_(3) solar cells.The unpackaged target devices possess a high stability,maintaining 80%of the initial PCE under simulated solar illumination exceeding 800 h. 展开更多
关键词 Perovskite solar cells FAPbI_(3) Homogeneous seeds Strain Phase stability
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Improved length of calcium sulfate crystal seeds and whiskers via ball milling and hydration treatment
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作者 Yuke Li Yuxin Liu +1 位作者 Jizhen Huang Yi Mei 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2024年第7期102-109,共8页
Elucidating the effect of growth periods on the quality of calcium sulfate whiskers(CSWs)prepared from calcium sulfate dihydrate(DH)is imperative.Herein,crystal seeds and whiskers were prepared from DH in a water–gly... Elucidating the effect of growth periods on the quality of calcium sulfate whiskers(CSWs)prepared from calcium sulfate dihydrate(DH)is imperative.Herein,crystal seeds and whiskers were prepared from DH in a water–glycerol system.Longer whiskers were obtained from crystal seeds prepared via hydration of DH for 30 s than via ball milling for 5 min followed by hydration for 20 s.The attachment of cetyltrimethyl ammonium bromide and glycerol additives to the whisker tops promoted whisker growth.The whisker sponges exhibited good thermal barrier properties and compression cycle stability. 展开更多
关键词 Hemihydrate gypsum whisker HYDRATION Ball milling/hydration Crystal seed Growth process
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Pumpkin seeds as nutraceutical and functional food ingredient for future:A review
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作者 Arunima Singh Vivek Kumar 《Grain & Oil Science and Technology》 CAS 2024年第1期12-29,共18页
Pumpkin belongs to the family of Cucurbitaceae,which comprises several species that has economical as well as agronomical importance.All parts of pumpkin are edible and laden with beneficial neutraceutical compounds.P... Pumpkin belongs to the family of Cucurbitaceae,which comprises several species that has economical as well as agronomical importance.All parts of pumpkin are edible and laden with beneficial neutraceutical compounds.Pumpkin seeds are valuable source protein which can help in eradicating protein malnutrition and lipids(rich in PUFAs)contains essential as well as non essential fatty acids which prevents from various ailments like cancer and other cardiovascular diseases.Since,seeds of pumpkin are abundant in macro(magnesium,phosphorous,potassium,sodium and calcium)and micro minerals(iron,copper,manganese,zinc and selenium),they can be used as an incredible dietary supplement which in turn helps in curbing various deficiency disorders.This review enlightens the characteristics of pumpkin seeds,process of valorization of pumpkin seeds and the effect of processing on their nutritional composition which have been studied currently with the aim to use this wonder seeds for human wellbeing.Pumpkin seeds possess many bioactive compounds like polyphenols,flavonoids,phytosterols and squalene which makes it a lucrative raw material for pharmacological and food industries.Pumpkin seeds work as anti-depressant and helps majorly in the treatment of benign prostate hyperplasia(BHP).Daily consumption of pumpkin seeds can reduce the chances of Alzheimer's and Parkinson's disease.Pumpkin seeds are rich in tocopherols and can be used for oil extraction for edible purposes and utilized in other food formulations for future use. 展开更多
关键词 Pumpkin seed Neutraceutical properties Nutritional composition Tocopherols SQUALENE Β-CAROTENE Waste valorization
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Soaking Rice Seeds in High Concentration Salt Solution Improved Salt Tolerance at the Seedling Stage
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作者 Jing LIN Weiwei CAO +1 位作者 Fan WANG Xianwen FANG 《Agricultural Biotechnology》 2024年第5期16-18,共3页
[Objectives]This study was conducted to enhance the salt tolerance of current rice varieties at the seedling stage and fulfill the urgent requirement for salt-tolerant rice varieties in coastal tidal flats.[Methods]Fo... [Objectives]This study was conducted to enhance the salt tolerance of current rice varieties at the seedling stage and fulfill the urgent requirement for salt-tolerant rice varieties in coastal tidal flats.[Methods]Four high-generation stable rice lines with diverse salt tolerance were employed as test materials,and four NaCl concentration gradients were established for seed soaking treatment.[Results]The seedling survival rate of line 151465 underwent significant alterations after soaking with four different salt concentrations,and the survival rate was the highest after treatment with 1.8%NaCl for 1 d,reaching 65.2%.The average survival rate of other three lines with different salt tolerance reached 62%after soaking with 1.8%NaCl for 1 d,which was significantly higher than those of the 2.2%NaCl and 0%NaCl treatments.[Conclusions]This study provides a basis for reducing the effect of abiotic stress on rice growth and development and improving the utilization rate of saline-alkali land. 展开更多
关键词 RICE Salt water seed soaking Salt tolerance seedling stag
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Design and Production of Infant Flours Based on Pumpkin Pulp Enriched with Cakes Extracted from Its Seeds
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作者 Koumba Hawa Toundoufedouno Kéloua Kourouma +2 位作者 Adama Moussa Sakho Karamoko Lansary Sylla Aboubacar Diallo 《Journal of Agricultural Chemistry and Environment》 2024年第2期192-207,共16页
The inclusion of composite flours in infant food at weaning time should be a priority for mothers. The aim of this project is to formulate infant flour based on pulp flour enriched with oilcake from these grains after... The inclusion of composite flours in infant food at weaning time should be a priority for mothers. The aim of this project is to formulate infant flour based on pulp flour enriched with oilcake from these grains after extraction of the oil. To do this, the elements were combined to obtain a regulatory formulation. Micro- and macronutrients, minerals, vitamins and tasting of the prepared porridge were determined. The results obtained were satisfactory. The moisture content of the fruit pulp was determined using oven-drying techniques: 92.2%, carbohydrates 6.00%, lipids 0.3%, ash 0.80%, proteins 1.10%, calcium 19.8%, phosphorus 42.6% and iron 0.4%. Furthermore, the carbohydrate content of flours composed of 5% insertion is 62.9 g to 48.8 g per 100 g, and the protein content of compound flours with 5% insertion is 15.9 g to 28.25 g per 100 g. On the other hand, the vitamin C and E contents of fresh pulp and oilcake are 25 mg, 13 mg and 21 mg respectively. However, only copper and β-carotene from 5% to 30% insertion remain invariant to the different insertion rates, with a value of 25 mg for copper and 0 µg for β-carotene. In addition, a variation in the degree of swelling of weaning flours compared with the standard from 3.95% at 5% insertion to 3.58 at 30% insertion was observed. The solubility of flours increases on the one hand with increases in the degree of insertion of the cakes. Flour formulated so many toward basicity. But the presence of traces of oil containing fatty acids can reduce this basicity. This study may be an alternative of industrial flours in infant nutrition. 展开更多
关键词 PUMPKIN seeds Oilcake Infant Flour Oil MICRONUTRIENTS
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A review:Research progress on multi-target neuroprotective effects of n-butylphthalide extracted from Apium graveolens seeds
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作者 Jiahui Huo Jingxian Ren +1 位作者 Xiaoxiao Huang Xiaoliang Wang 《Asian Journal of Traditional Medicines》 2024年第5期275-284,共10页
Apium graveolens,an annual herb belonging to the family of Apiaceae,is widely distributed in North and South America,Southern Europe,Africa and Asia.Apium graveolens seeds have a rich history in traditional Chinese me... Apium graveolens,an annual herb belonging to the family of Apiaceae,is widely distributed in North and South America,Southern Europe,Africa and Asia.Apium graveolens seeds have a rich history in traditional Chinese medicine for treating hypertension,headaches,vertigo and epilepsy.N-butylphthalide,originally extracted from Apium graveolens seeds,represents a first-in-class drug developed independently in China.Its broad pharmacological activities on nervous system disorders have garnered significant attention from researchers globally.This review focuses on the pharmacological research of n-butylphthalide on central nervous system diseases,including ischemic stroke,Alzheimer’s disease,Parkinson’s disease and amyotrophic lateral sclerosis.The purpose is to pave the way for future study on the mechanistic targets of n-butylphthalide. 展开更多
关键词 Apium graveolens seeds n-butylphthalide central nervous system diseases
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Study of Dielectric Relaxation of Insulating Oil from Lagenaria siceraria Seeds
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作者 Michael Koumbou Piembe Jean Ndoumbe Charles Hubert Kom 《World Journal of Engineering and Technology》 2024年第4期821-835,共15页
The present work concerns the study of the dielectric relaxation of dielectric oil based on Lagenaria siceraria (calabash) seeds. Dielectric spectroscopy was used to measure the loss angle, the dielectric constant and... The present work concerns the study of the dielectric relaxation of dielectric oil based on Lagenaria siceraria (calabash) seeds. Dielectric spectroscopy was used to measure the loss angle, the dielectric constant and the electrical modulus. Three relaxation processes in calabash oil were identified. It was also found that the relative permittivity decreases with increasing temperature and frequency. A study of the imaginary part of the electrical modulus was done and revealed a relaxation process at low frequencies. At higher frequencies, the dielectric relaxation is thermally activated. The increase in temperature leads to a decrease in the relaxation rate. The result obtained indicates that relaxation type is not of the Debye type in the high-frequency region. The Cole-Cole model of the imaginary part of the permittivity as a function of its real part in calabash oil for different temperatures was drawn and analyzed. It shows the existence of a negative temperature coefficient of resistance in the fluid and helps identifying a relaxation process in the conductivity of the sample studied. It highlights the presence of Debye relaxation which characterizes the presence of an abnormal dispersion of the dielectric constant over a frequency range. Calabash seed oil exhibits better dielectric constant (relative permittivity) compared to other oils. 展开更多
关键词 Dielectric Relaxation Electric Modulus Calabash seed Oil Dielectric Spectroscopy Cole-Cole Model Debye Model
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一种基于Seeds集和成对约束的半监督聚类算法 被引量:7
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作者 常瑜 梁吉业 +1 位作者 高嘉伟 杨静 《南京大学学报(自然科学版)》 CAS CSCD 北大核心 2012年第4期405-411,共7页
半监督聚类研究如何利用少量的监督信息来提高聚类性能,目前已经成为机器学习领域的一个研究热点.现有的大多数半监督聚类方法没有综合考虑Seeds集和成对约束这两种监督信息,因而提出了一种基于Seeds集和成对约束的半监督聚类算法.该算... 半监督聚类研究如何利用少量的监督信息来提高聚类性能,目前已经成为机器学习领域的一个研究热点.现有的大多数半监督聚类方法没有综合考虑Seeds集和成对约束这两种监督信息,因而提出了一种基于Seeds集和成对约束的半监督聚类算法.该算法运用Tri-training算法扩充Seeds集,结合成对约束优化Seeds集并指导聚类过程.实验结果表明,该算法能够有效提高聚类性能. 展开更多
关键词 半监督聚类 seeds 成对约束
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Physiological characteristics changes of Aesculus chinensis seeds during natural dehydration 被引量:8
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作者 喻方圆 杜艳 沈永宝 《Journal of Forestry Research》 SCIE CAS CSCD 2006年第2期103-106,共4页
A study was conducted to determine the physiological characteristics changes of Aesculus chinensis seeds during natural dehydration in 2003. The results showed that A. chinensis seeds were recalcitrant with being high... A study was conducted to determine the physiological characteristics changes of Aesculus chinensis seeds during natural dehydration in 2003. The results showed that A. chinensis seeds were recalcitrant with being highly desiccation-sensitive. The seed moisture content of fresh fruits was higher than 60%. When the seeds were naturally dried for 30 days, their moisture content declined to 30.2% and their viability was completely lost. The seed germination percentage had a small increase at the beginning of desiccation and then decreased rapidly. The relative electrical conductivity of the A. chinensis seeds increased along with a decrease in seed moisture content. However, there was an abnormal increase in relative electrical conductivity when the seed moisture content was between 53.7% and 50.9%. Superoxide dismutase (SOD) activity decreased rapidly in the period of desiccation except for an abnormality when the seed moisture content was between 53.7% and 50.9%. Malondialdehyde (MDA) content increased slowly at the early stage of desiccation and then rose rapidly after the moisture content was below 50.9%. The soluble sugar content in seeds slowly increased with the increasing period of desiccation. The seed germination percentage was at the high level when seed moisture content was in range of 47%- 60%, which suggests that this was the optimum moisture content for maintaining A. chinensis seed viability. 展开更多
关键词 Aesculus chinensis seeds Air drying Physiological characteristics seedmoisture content seed germination percentage Superoxide dismutase (SOD) activity Malondialdehyde(MDA) content seed electrical conductivity
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Effects of Excessive Mg2+ on the Germination Characteristics of Crop Seeds 被引量:23
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作者 马恩 付莎莎 张宏波 《Agricultural Science & Technology》 CAS 2008年第2期26-29,共4页
[ Objective ] The research aimed to reveal theeffects of excessive Mg^2+ on the germination characteristics of maize and soybean. [ Method ] Eleven concentration gradients of Mg^2+ including 0, 40, 80, 120, 160,200,... [ Objective ] The research aimed to reveal theeffects of excessive Mg^2+ on the germination characteristics of maize and soybean. [ Method ] Eleven concentration gradients of Mg^2+ including 0, 40, 80, 120, 160,200,240,280,320,360 and 400 mmol/L were set up to study the effects of different treatments on such indices as the germination potential, germination rate, fresh weight, dry weight, root length, plant height and stem diameter of maize and soybean. [ Result] With the increasing of Mg^2+ concentration, the germination of maize delayed and the germination rate of soybean obviously decreased, reaching the significant difference at 0.05 level. When Mg^2+ concentration increased, the fresh weight and dry weight of maize and soybean decreased, but maize and soybean showed some adaptability. The growth of radicles and seedlings in maize and soybean were obviously inhibited by Mg^2+ , and atrophy and dysplasia phenomena appeared. [ Conclusion] Excessive Mg^2+ stress has different effects on the germination potential and germination rate of different crops and has obvious poisoning effects on the root and stem growth of crops. 展开更多
关键词 Mg^2+ stress MAIZE SOYBEAN seeds GERMINATION
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Increased Storability of Haloxylon ammodendron Seeds in Ultra-drying Storage 被引量:10
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作者 黄振英 张新时 +2 位作者 郑光华 景新明 林坚 《Acta Botanica Sinica》 CSCD 2002年第2期239-241,共3页
梭梭 (HaloxylonammodendronBge .)的种子为短命种子 ,在自然状态下 ,种子的含水量为 8.5 % ,寿命约为 10个月。将梭梭种子含水量降至 2 .5 %和 1.4% ,其耐贮藏力增强。经过 5 0℃下 5d和 10d的人工加速老化后 ,超干种子表现出较强的抗... 梭梭 (HaloxylonammodendronBge .)的种子为短命种子 ,在自然状态下 ,种子的含水量为 8.5 % ,寿命约为 10个月。将梭梭种子含水量降至 2 .5 %和 1.4% ,其耐贮藏力增强。经过 5 0℃下 5d和 10d的人工加速老化后 ,超干种子表现出较强的抗老化能力。与对照相比 ,超干种子具有较高的萌发率、活力指数及较长的根 。 展开更多
关键词 Haloxylon ammodendron short-lived seed ultra-drying storage
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Studies on Membrane Function and Sugar Components of Ultradried Seeds 被引量:9
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作者 汪晓峰 景新明 +2 位作者 林坚 郑光华 蔡早 《Acta Botanica Sinica》 CSCD 2003年第1期23-31,共9页
The effects of ultradry storage on the activity of ATPase and fluidity of plasma membrane in Chinese cabbage (Brassica pekinensis (Lour.) Rupr.) and elm ( Ulmus pumila L.) seeds were investigated. The results indicate... The effects of ultradry storage on the activity of ATPase and fluidity of plasma membrane in Chinese cabbage (Brassica pekinensis (Lour.) Rupr.) and elm ( Ulmus pumila L.) seeds were investigated. The results indicated that no significant differences in the activity of ATPase and the micro- viscosity of plasma membrane of ultradried (UD) seeds could be found as compared to the control seeds stored under -20 degreesC, although there was a little adverse effect on the seeds with extreme dehydration. The results were consistent with higher vigor level of UD seeds. This implied that ultradry seed storage could protect the integrity of the membrane, maintain its physiological function and improve the storability of seeds. The relationship between sugar and desiccation tolerance of UD seeds was analysed using the HPLC. The results showed that the ratio of reducing to nonreducing sugar was lower in UD seeds than that in control. The content of sucrose and stachyose in elm and Chinese cabbage UD seeds was related to their desiccation tolerance, while no stachyose was detected in corn (Zea mays L.) seeds. This could be one of the reasons for its sensitivity to desiccation. 展开更多
关键词 ultradry seed storage ATPASE micro-viscosity soluble sugar
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一种基于Seeds集和成对约束的主动半监督聚类算法 被引量:2
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作者 陈志雨 王慧君 +1 位作者 胡明 刘钢 《吉林大学学报(理学版)》 CAS CSCD 北大核心 2017年第3期664-672,共9页
针对半监督聚类算法中监督信息使用不充分,监督信息中信息含有量低的问题,提出一种结合主动学习的半监督聚类算法.首先结合使用数据的类别标记和成对约束信息,指导Kmeans聚类过程,设计出一种基于Seeds集和成对约束的半监督聚类算法SC-Km... 针对半监督聚类算法中监督信息使用不充分,监督信息中信息含有量低的问题,提出一种结合主动学习的半监督聚类算法.首先结合使用数据的类别标记和成对约束信息,指导Kmeans聚类过程,设计出一种基于Seeds集和成对约束的半监督聚类算法SC-Kmeans;其次将主动学习算法引入到SC-Kmeans中,以尽量小的代价选取信息含有量更高的监督信息,提高SC-Kmeans算法的聚类精度;最后在UCI标准数据集上进行仿真实验.实验结果表明,该算法取得了较好的聚类效果,有效提高了聚类准确率. 展开更多
关键词 半监督聚类 Kmeans算法 成对约束 seeds 主动学习
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Callus Induction and Plant Regeneration from Mature Seeds of Perennial Ryegrass 被引量:15
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作者 曾升坚 卞建春 +2 位作者 方钲 张冬霞 邹新海 《Agricultural Science & Technology》 CAS 2009年第6期33-36,共4页
Objective The aim was to explore callus induction and plant regeneration of perennial ryegrass, as well as provide the foundation for transgenic research on perennial ryegrass.[ Methed] Mature seeds of perennial ryegr... Objective The aim was to explore callus induction and plant regeneration of perennial ryegrass, as well as provide the foundation for transgenic research on perennial ryegrass.[ Methed] Mature seeds of perennial ryegrass were used as explants to study the effects of different hormone compositions on callus induction, proliferation and plant differentiation. Result The result showed that the induction rate achieved its highest on 2,4-D of 8 mg/L combining with 6-BA of 0.025 mg/L, which was up to 56.42%. Callus were differentiated after two to three generations, the highest differentiation rate 34.14% was achieved in the medium contained MS medium with 6-BA of 2 mg/L, and the differentiation rate was obviously affected by the callus condition after proliferation. The root inducing medium, containing 0.5 mg/L NAA and MS medium with half of macroelement, gained 98% root inducing rate. Conclusien A high frequency genetic regeneration system was established. 展开更多
关键词 Perennial ryegrass Mature seed Tissue culture Plant regeneration
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Analysis of Amylase and Superoxide Dismutase Isozymes During the Germination Process of Emmenopterys henryi Oliv Seeds 被引量:17
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作者 刘国勇 彭丽娟 陈发菊 《Agricultural Science & Technology》 CAS 2009年第2期6-8,19,共4页
[ Objective] The study was to understand the changes of amylase(AMY) and superoxide dismutase(SOD) isozymes during the ger- mination process of Emmenopterys henryi Oliv seeds. [ Metbod] By employing polyacrylamide... [ Objective] The study was to understand the changes of amylase(AMY) and superoxide dismutase(SOD) isozymes during the ger- mination process of Emmenopterys henryi Oliv seeds. [ Metbod] By employing polyacrylamide gel electrophoresis method, the expressions of AMY and SOD isozymes during seed germination process were analyzed. ~ Result] The main AMY bands remained strong during the whole peri- od and a new band A2 appeared in the middle and late period of seed germination. Some new SOD bands occurred at the early stage, then be- came weak or disappeared in the middle period, and band S6 became intense in the late peried. [ Conclusion.] The expression of AMY and SOD isozyme gene has temporal difference during germination of E. henryi Oliv seeds. 展开更多
关键词 Emmenopterys henryi Oliv Amylase isozymes Superoxide dismutase isozyme seed germination
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Catalytic performance of biological method seeds on jarosite process 被引量:5
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作者 李海军 杨洪英 陈国宝 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2016年第2期557-564,共8页
The catalytic performance on jarosite process of jarosite seeds via biosynthesis and chemical processes were studied, respectively. The SEM and XRD results showed that biosynthetic jarosite seeds (BIO seeds) had smo... The catalytic performance on jarosite process of jarosite seeds via biosynthesis and chemical processes were studied, respectively. The SEM and XRD results showed that biosynthetic jarosite seeds (BIO seeds) had smooth surface and mainly consisted of potassium jarosite. The chemical synthesis jarosite seeds (CHM seeds) had a loose cauliflower-like surface and mainly consisted of hydronium jarosite. The catalytic performance of BIO seeds was better than that of CHM seeds on the formation of final jarosite product. The induction time can be shortened to 20 min, the reaction temperature can be reduced to only 75 ℃, and the initial reaction speed was enhanced obviously, up to 3.933%/min. The crystallinity of final jarosite product using BIO seeds can achieve 97.22%, while it was only 12.89% without seeds. This indicates that the precipitation process of jarosite is more complete with BIO seeds. 展开更多
关键词 jarosite seed jarosite process induction period temperature initial precipitate rate
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