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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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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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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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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 Comparative Study on the Quality Components Between Self Pollinated Seeds and Naturally Pollinated Seeds in Brassica napus L. in Sichuan Ecological Region 被引量:2
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作者 张锦芳 蒲晓斌 +4 位作者 李浩杰 黄驰 李蒲 张谦 蒋梁材 《Agricultural Science & Technology》 CAS 2009年第1期19-21,80,共4页
[ Objective] This study was to reveal the differences in crude fat and glucosinolates between self pollinated seeds and naturally pollinated seeds in Brassica napus in sichuan ecological region.. [ Method] Near-infrar... [ Objective] This study was to reveal the differences in crude fat and glucosinolates between self pollinated seeds and naturally pollinated seeds in Brassica napus in sichuan ecological region.. [ Method] Near-infrared spectroscopy method (NIRS) was employed to measure the quality components in self pollinated seeds and naturally pollinated seeds of 861 shares of Brassica napus from Sichuan ecological region. And correlation analysis and regression analysis were conducted based on the experimental data via SPSS (statistics package for social science). [ Result] The contents of crude fat in the self pollinated seeds were commonly a higher than that in the naturally pollinated seeds at 0.01 significant level; while the contents of glucosinolates in the self pollinated seeds and the naturally pollinated seeds were insignificantly different. Both the correlation relationship and linear regression for the crude fat between the self pollinated seeds and naturally pollinated seeds reached the significant level. The regression equations for the contents of crude fat(y1 ) and glucosinolates( y2 ) in the naturally pollinated seeds and of crude fat( x1 ) and glucosinolates( x2 ) in self pollinated seeds were respectively determined to be y1 = 16.844 +0.614x1 and y2 = -0.620 + 1.017 x2. [ Conclusion] In Brassica napus breeding, crude fat in naturally pollinated seeds should be emphatically taken into account, meanwhile concurrently considering that in self pollinated seeds; while glucosinolates in both the self pollinated seeds and the naturally pollinated seeds must be simultaneously concerned. 展开更多
关键词 Brassica napus L. Self pollinated seeds Naturally pollinated seeds Content of crude fat Content of gluccsinolates Near-infrared spectroscopy method
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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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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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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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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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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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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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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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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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Effect of priming on the germination of Peltophorum dubium seeds under water stress 被引量:3
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作者 张万里 李雷鸿 祖元刚 《Journal of Forestry Research》 CAS CSCD 2004年第4期287-290,共4页
Peltophorum dubium seeds provided by Anhembi, SP were scarified in 98% H2SO4 for 15 min to overcome mechani-cal dormancy. Seeds were primed in solutions of 0.2% Captan at 10 C and 27C, PEG 6000 -1.0 MPa at 10C and 27... Peltophorum dubium seeds provided by Anhembi, SP were scarified in 98% H2SO4 for 15 min to overcome mechani-cal dormancy. Seeds were primed in solutions of 0.2% Captan at 10 C and 27C, PEG 6000 -1.0 MPa at 10C and 27C, 0.5 mol KNO3, 0.75 Mol KNO3, 1.0 Mol KNO3. Eight treatments including the primed seeds and nonprimed seeds, five replicates with 100 seeds for each treatment, were set to 15-cm-Petri dish with double filter paper moistened with testing solution PEG in refrigerator at 27C. For the experiments of all the groups, osmotic potential were 0.0, -0.2, -0.4, -0.6, -0.8, -1.0, -1.2, and -1.4 MPa. P. dubium seeds were also set to water stress experiment in rolled paper with PEG solutions from 0.0 to -1.0 M Pa. Germination percentage decreased with the increase of PEG concentration. Control group had a better germination percentage than other groups. Germination hardly occurred in PEG -1.4 MPa. 展开更多
关键词 PRIMING Osmotic potential GERMINATION seeds Peltophorum dubium
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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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Studies on Ultra-dry Storage and Genetic Stability of Vegetable Seeds 被引量:2
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作者 孟淑春 李秀清 +2 位作者 马连平 卢艳 刘玲 《Agricultural Science & Technology》 CAS 2011年第12期1853-1856,共4页
[Objective] To study the long-term ultra-dry storage method and genetic stability of vegetable seeds.[Method] Seeds of Lycopersicum esculentum,Raphanus satuvus and Apium graveolen.were chosen as material.The changes o... [Objective] To study the long-term ultra-dry storage method and genetic stability of vegetable seeds.[Method] Seeds of Lycopersicum esculentum,Raphanus satuvus and Apium graveolen.were chosen as material.The changes of seed vigor,viability and genetic stability after ultra-storage were discussed by studying the seed potentiality,shoot length,germination percentage and the chromosome aberration rate of root tip cells.[Results] Maintaining the low moisture content,different vegetable species had different storage effects of the long-term storage seeds under normal temperature.The Lycopersicum esculentum and Raphanus satuvus seeds were more suitable to ultra-dry storage at normal temperature,and could keep good genetic stability,while the seeds of Apium graveolen had bad performance.[Conclusion] This study established the foundation of studying ultra-dry storage of vegetable seeds. 展开更多
关键词 seeds Ultra-dry storage Chromosome aberration Genetic stability
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Comparison between the Use of Loose and Stranded Seeds in Prostate Brachytherapy in Brazil
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作者 Fernando SPeleias Jr. Carlos A.Zeituni +3 位作者 Elisa C.M.Rostelato Carla D.Souza Fabio R.Mattos Marcos A.G.Benega 《Open Journal of Urology》 2012年第3期206-209,共4页
Cancer is a leading cause of death worldwide. In 2030, 26.4 million new cases will be diagnosed, with 17 million deaths accounted worldwide. Prostate cancer is the sixth most common type in the world, and the second m... Cancer is a leading cause of death worldwide. In 2030, 26.4 million new cases will be diagnosed, with 17 million deaths accounted worldwide. Prostate cancer is the sixth most common type in the world, and the second most commom in men. For Brazil, the number of new cases of prostate cancer in 2010 is estimated to 52,350. Treatment of prostate cancer may be by surgery, radiation or even vigilant observation. A method of radiotherapy which has been extensively used is brachytherapy, where Iodine-125 seeds are placed inside or next to the area requiring treatment. Iodine seeds can be introduced loose seeds or stranded in bioabsorbable polymers in order to increase the dosimetric coverage of the prostate and reducing the chance of seed migration. Data were gathered concerning the commercialization of loose seeds and stranded seeds, between 2005 and 2011, in Brazil. It was noted that the number of stranded seeds commercialized in Brazil (around 80%) has always been much greater than the number of loose seeds, reaching 90% last year. The main reason is the reduction of the seed migration events into other parts of the body, since there is a potential hazard even considering that no harmful effect has been observe. The data regarding dosimetry are still controversial, since the seeds that migrate is normally no more than 1%. 展开更多
关键词 CANCER PROSTATE BRACHYTHERAPY Iodine-125 seeds Loose seeds Stranded seeds
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A Method for Rapid Salt-extraction of High-quality Genomic DNA from Plant Seeds 被引量:1
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作者 张富丽 刘勇 +4 位作者 宋君 尹全 代晓航 雷绍荣 游米沙 《Agricultural Science & Technology》 CAS 2012年第3期485-488,共4页
[Objective] This study aimed to explore an effective method for rapid salt- extraction of high-quality genomic DNA from dried seeds of plants. [Method] Seeds of seven varieties of crops were ground into powder. A hund... [Objective] This study aimed to explore an effective method for rapid salt- extraction of high-quality genomic DNA from dried seeds of plants. [Method] Seeds of seven varieties of crops were ground into powder. A hundred milligrams of seed powder was added to extracting solution for high salt-extraction of genomic DNA. The yield and quality of extracted DNA were determined by using ultramicro UV/Vis spectrophotometer detection method, PCR and restriction enzyme digestion. [Result] About 619.67-1 811.21 ng of genomic DNA was extracted from per 100 mg of dried seed powder of seven varieties of conventional crops. A260/A280 ratios of the obtained DNA solution all ranged from 1.87 to 2.07, the purity and quality of PCR were suitable for PCR and restriction enzyme digestion. Clear target bands of specific endogenous gene fragments of seven varieties of crops were amplified by PCR, and the obtained DNA could be fully digested with EcoRV and Hindlll.[Conclusion] This method could be used for rapid extraction of high-quality genomic DNA from dried seeds. 展开更多
关键词 Genomic DNA Polymerase chain reaction High salt extraction Dried seeds
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Comparison of Methods for Ultra-drying of Chinese Chive Seeds 被引量:1
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作者 孟淑春 李秀清 +1 位作者 马连平 刘玲 《Agricultural Science & Technology》 CAS 2013年第4期598-601,共4页
[Objective] This study aimed to identify the ultra-drying method most suitable for the storage of Chinese chive seeds through comparing different ultra-drying meth- ods. [Method] Through setting treatments including f... [Objective] This study aimed to identify the ultra-drying method most suitable for the storage of Chinese chive seeds through comparing different ultra-drying meth- ods. [Method] Through setting treatments including freezing, silica gel drying and heating drying at 50℃ as well as two controls, the effects of different drying methods for storing ultra-dried Chinese chive seeds were compared. [Result] There were no significant differences in the germination rate and seedling length between Chinese chive seeds treated with heating drying at 50℃ and those treated with either freezing or get drying at the initial stage of the storage. Storing of Chinese chive seeds previously treated with either heating drying at 50℃, or freezing or gel drying for 0-98 months at 20℃ hadn't caused any adverse effect on the germination rate of seeds. And the effect of different storage conditions on seedling length displayed earlier than that on the germination rate. There was no significant difference on seedling length between seeds treated with heating drying at 50℃ and those treated with freezing drying after stored for as long as 98 months, revealing similar efficacy on storing seeds. [Conclusion] Freezing drying requires huge investment and cost for perennial running, and silica gel drying is slow in drying and time-consuming. By contrast, heating drying at 50℃ is an economic and simple method, which can enable the Chinese chive seeds to sustain a longevity of eight years or more. 展开更多
关键词 Chinese chive seeds Ultra-drying methods Seed longevity
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