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Correction to:Assembly-level analysis on temperature coefficient of reactivity in a graphite-moderated fuel salt reactor fueled with low-enriched uranium
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作者 Xiao-Xiao Li De-Yang Cui +3 位作者 Chun-Yan Zou Jian-Hui Wu Xiang-Zhou Cai Jin-Gen Chen 《Nuclear Science and Techniques》 SCIE EI CAS CSCD 2024年第2期234-235,共2页
Following publication of the original article,the authors observed that both Fig.5 and Fig.4 depict the same image.Figure 5 was inaccurately referenced and displayed.The correct Fig.5 is copied below:The original arti... Following publication of the original article,the authors observed that both Fig.5 and Fig.4 depict the same image.Figure 5 was inaccurately referenced and displayed.The correct Fig.5 is copied below:The original article has been updated. 展开更多
关键词 FUEL enriched REACTIVITY
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Enriched Constant Elements in the Boundary Element Method for Solving 2D Acoustic Problems at Higher Frequencies
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作者 Zonglin Li Zhenyu Gao Yijun Liu 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第3期2159-2175,共17页
The boundary element method(BEM)is a popular method for solving acoustic wave propagation problems,especially those in exterior domains,owing to its ease in handling radiation conditions at infinity.However,BEM models... The boundary element method(BEM)is a popular method for solving acoustic wave propagation problems,especially those in exterior domains,owing to its ease in handling radiation conditions at infinity.However,BEM models must meet the requirement of 6–10 elements per wavelength,using the conventional constant,linear,or quadratic elements.Therefore,a large storage size of memory and long solution time are often needed in solving higher-frequency problems.In this work,we propose two new types of enriched elements based on conventional constant boundary elements to improve the computational efficiency of the 2D acoustic BEM.The first one uses a plane wave expansion,which can be used to model scattering problems.The second one uses a special plane wave expansion,which can be used tomodel radiation problems.Five examples are investigated to showthe advantages of the enriched elements.Compared with the conventional constant elements,the new enriched elements can deliver results with the same accuracy and in less computational time.This improvement in the computational efficiency is more evident at higher frequencies(with the nondimensional wave numbers exceeding 100).The paper concludes with the potential of our proposed enriched elements and plans for their further improvement. 展开更多
关键词 enriched boundary elements constant elements 2D acoustic problems higher frequency
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Production and Evaluation of the Nutritional and Functional Qualities of “Adakwa” Enriched with Waste Biomass of Traditional Brewer’s Spent Grain as a Functional Staple Food
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作者 Tankem Tankem Pride Ndasi Ngwasiri +4 位作者 Wilson Agwanande Ambindei Makebe Calister Wingang Ngwa Martin Ngwabie Martin Benoit Ngassoum Ejoh Richard Aba 《Advances in Chemical Engineering and Science》 2023年第4期265-288,共24页
Brewers’ spent grains constitute a nutrient-rich valuable and highly under-utilized by-product of the beer industry produced in large amounts all through the year. This bio-resource is a very good candidate for valor... Brewers’ spent grains constitute a nutrient-rich valuable and highly under-utilized by-product of the beer industry produced in large amounts all through the year. This bio-resource is a very good candidate for valorization, due to environmental and economic concerns, using biotechnological processing, particularly for food enrichment. This study was undertaken to evaluate the effect of fortification of Adakwa with traditional brewers’ spent grains (TBSG) on its physicochemical and nutritional properties as well as its acceptability using an experimental design. Four (4) samples of Adakwa were produced with TBSG incorporated rates of 0% (control sample), 10%, 20%, and 30% and evaluated. Using an experimental design, the effect of process parameters, including the TBSG incorporation rate, cooking time, and cooking temperatures on the physicochemical and nutritional properties of the Adakwa were evaluated while the 9-point hedonic scale was used to evaluate the sensory properties and its overall acceptability: carbohydrate, protein, crude fibre, cellulose, polyphenol, antioxidant activity (FRAP and DPPH). The water absorption activity values were 81.2 ± 0.04, 4.55 ± 0.05, 9.73 ± 0.23, 3.31 ± 0.05, 6.73 ± 0.23, 1.60 ± 0.09, 28.85 ± 0.8 and 117 ± 3.54 respectively for 0% TBSG (control);86.8 ± 0.01, 1.81± 0.20, 16.22 ± 0.16, 5.54 ± 0.69, 6.01 ± 0.16, 6.59 ± 0.03, 25.89 ± 0.94 and 475.0 ± 21.21 respectively for 30% TBSG. The sample with a high nutrient content was further produced using a central composite design and the factors studied were temperature and time, with responses, crude fiber, and FRAP content. The optimum production condition was: % TBSG: 47.06%;temperature: 123.17℃;Time: 30.34 mins. The sample with 47% TBSG had the best overall acceptability after sensory evaluation with sensory scores of: 5.45 ± 0.76, 7.9 ± 0.79, 8.0 ± 1.0, 7.10 ± 0.16, 8.5 ± 1.6, 7.6 ± 0.98 for color, taste, aroma, mouthfeel, texture and overall acceptability respectively. Thus TBSG can be used to improve the physicochemical and nutritional properties of adakwa. 展开更多
关键词 Biomass Brew-Waste Spent Grain Valorisation Adakwa ENRICHMENT
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An enriched environment increases the expression of fibronectin type Ⅲ domain-containing protein 5 and brain-derived neurotrophic factor in the cerebral cortex of the ischemic mouse brain 被引量:12
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作者 Ke-Wei Yu Chuan-Jie Wang +7 位作者 Yi Wu Yu-Yang Wang Nian-Hong Wang Shen-Yi Kuang Gang Liu Hong-Yu Xie Cong-Yu Jiang Jun-Fa Wu 《Neural Regeneration Research》 SCIE CAS CSCD 2020年第9期1671-1677,共7页
Many studies have shown that fibronectin type III domain-containing protein 5(FDNC5) and brain-derived neurotrophic factor(BDNF) play vital roles in plasticity after brain injury. An enriched environment refers to an ... Many studies have shown that fibronectin type III domain-containing protein 5(FDNC5) and brain-derived neurotrophic factor(BDNF) play vital roles in plasticity after brain injury. An enriched environment refers to an environment that provides animals with multi-sensory stimulation and movement opportunities. An enriched environment has been shown to promote the regeneration of nerve cells, synapses, and blood vessels in the animal brain after cerebral ischemia;however, the exact mechanisms have not been clarified. This study aimed to determine whether an enriched environment could improve neurobehavioral functions after the experimental inducement of cerebral ischemia and whether neurobehavioral outcomes were associated with the expression of FDNC5 and BDNF. This study established ischemic mouse models using permanent middle cerebral artery occlusion(pMCAO) on the left side. On postoperative day 1, the mice were randomly assigned to either enriched environment or standard housing condition groups. Mice in the standard housing condition group were housed and fed under standard conditions. Mice in the enriched environment group were housed in a large cage, containing various toys, and fed with a standard diet. Sham-operated mice received the same procedure, but without artery occlusion, and were housed and fed under standard conditions. On postoperative days 7 and 14, a beam-walking test was used to assess coordination, balance, and spatial learning. On postoperative days 16–20, a Morris water maze test was used to assess spatial learning and memory. On postoperative day 15, the expression levels of FDNC5 and BDNF proteins in the ipsilateral cerebral cortex were analyzed by western blot assay. The results showed that compared with the standard housing condition group, the motor balance and coordination functions(based on beam-walking test scores 7 and 14 days after operation), spatial learning abilities(based on the spatial learning scores from the Morris water maze test 16–19 days after operation), and memory abilities(based on the memory scores of the Morris water maze test 20 days after operation) of the enriched environment group improved significantly. In addition, the expression levels of FDNC5 and BDNF proteins in the ipsilateral cerebral cortex increased in the enriched environment group compared with those in the standard housing condition group. Furthermore, the Pearson correlation coefficient showed that neurobehavioral functions were positively associated with the expression levels of FDNC5 and BDNF(r = 0.587 and r = 0.840, respectively). These findings suggest that an enriched environment upregulates FDNC5 protein expression in the ipsilateral cerebral cortex after cerebral ischemia, which then activates BDNF protein expression, improving neurological function. BDNF protein expression was positively correlated with improved neurological function. The experimental protocols were approved by the Institutional Animal Care and Use Committee of Fudan University, China(approval Nos. 20160858 A232, 20160860 A234) on February 24, 2016. 展开更多
关键词 beam-walking test brain-derived neurotrophic factor cerebral ischemia correlation analysis enriched environment fibronectin typeⅢdomain-containing protein 5 Morris water maze task neural plasticity NEUROPROTECTION permanent middle cerebral artery occlusion
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Synthesis of Enriched 10B Boric Acid of Nuclear Grade 被引量:8
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作者 Zhang Lei 《Transactions of Tianjin University》 EI CAS 2014年第6期458-462,共5页
An economic and effective method of preparing enriched 10B boric acid was established by chemical reactionof enriched 10BF3 and CaCO3. A process of boron trifluoride reacting with water was investigated under certainc... An economic and effective method of preparing enriched 10B boric acid was established by chemical reactionof enriched 10BF3 and CaCO3. A process of boron trifluoride reacting with water was investigated under certainconditions. Calcium carbonate was selected to counteract hydrofluoric acid followed on. Some key operation factorswere investigated, such as temperature, reaction time and the ratio of CaCO3 to 10BF3. The results showed that the yieldof enriched 10B boric acid could reach 97. 2% and the purity was up to 94. 1% under the following conditions: the temperaturewas 50-60,℃, the reaction time was 28 h and the ratio of CaCO3 to 10BF3 was 4. In addition, after recrystallizationand titration analysis, the purity of the product could reach over 99. 2% from 94.1%. 展开更多
关键词 enriched 10B boric ACID BORON TRIFLUORIDE CALCIUM CARBONATE fluoboric ACID hydrogen FLUORIDE
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Molecular and physiological characterization of the effects of auxin-enriched rootstock on grafting 被引量:6
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作者 Longmei Zhai Xiaomin Wang +7 位作者 Dan Tang Qi Qi Huseyin Yer Xiangning Jiang Zhenhai Han Richard McAvoy Wei Li Yi Li 《Horticulture Research》 SCIE 2021年第1期926-938,共13页
Grafting is a highly useful technique,and its success largely depends on graft union formation.In this study,we found that root-specific expression of the auxin biosynthetic gene iaaM in tobacco,when used as rootstock... Grafting is a highly useful technique,and its success largely depends on graft union formation.In this study,we found that root-specific expression of the auxin biosynthetic gene iaaM in tobacco,when used as rootstock,resulted in more rapid callus formation and faster graft healing.However,overexpression of the auxin-inactivating iaaL gene in rootstocks delayed graft healing.We observed increased endogenous auxin levels and auxin-responsive DR5::GUS expression in scions of WT/iaaM grafts compared with those found in WT/WT grafts,which suggested that auxin is transported upward from rootstock to scion tissues.A transcriptome analysis showed that auxin enhanced graft union formation through increases in the expression of genes involved in graft healing in both rootstock and scion tissues.We also observed that the ethylene biosynthetic gene ACS1 and the ethylene-responsive gene ERF5 were upregulated in both scions and rootstocks of the WT/iaaM grafts.Furthermore,exogenous applications of the ethylene precursor ACC to the junction of WT/WT grafts promoted graft union formation,whereas application of the ethylene biosynthesis inhibitor AVG delayed graft healing in WT/WT grafts,and the observed delay was less pronounced in the WT/iaaM grafts.These results demonstrated that elevated auxin levels in the iaaM rootstock in combination with the increased auxin levels in scions caused by upward transport/diffusion enhanced graft union formation and that ethylene was partially responsible for the effects of auxin on grafting.Our findings showed that grafting success can be enhanced by increasing the auxin levels in rootstocks using transgenic or gene-editing techniques. 展开更多
关键词 UNION enriched CHARACTERIZATION
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A novel viewpoint in glaucoma therapeutics: enriched environment 被引量:1
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作者 María F.González Fleitas Damián Dorfman Ruth E.Rosenstein 《Neural Regeneration Research》 SCIE CAS CSCD 2022年第7期1431-1439,共9页
Glaucoma is one of the world’s most frequent visual impairment causes and leads to selective damage to retinal ganglion cells and their axons.Despite glaucoma’s most accepted risk factor is increased intraocular pre... Glaucoma is one of the world’s most frequent visual impairment causes and leads to selective damage to retinal ganglion cells and their axons.Despite glaucoma’s most accepted risk factor is increased intraocular pressure(IOP),the mechanisms behind the disease have not been fully elucidated.To date,IOP lowering remains the gold standard;however,glaucoma patients may still lose vision regardless of effective IOP management.Therefore,the exclusive IOP control apparently is not enough to stop the disease progression,and developing new resources to protect the retina and optic nerve against glaucoma is a goal of vast clinical importance.Besides pharmacological treatments,environmental conditions have been shown to prevent neurodegeneration in the central nervous system.In this review,we discuss current concepts on key pathogenic mechanisms involved in glaucoma,the effect of enriched environment on these mechanisms in different experimental models,as well as recent evidence supporting the preventive and therapeutic effect of enriched environment exposure against experimental glaucomatous damage.Finally,we postulate that stimulating vision may become a non-invasive and rehabilitative therapy that could be eventually translated to the human disease,preventing glaucoma-induced terrible sequelae resulting in permanent visual disability. 展开更多
关键词 brain-derived neurotrophic factor chondroitin sulfate enriched environment GLAUCOMA optic nerve axons optic nerve glia retinal ganglion cells visual stimulation
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An enriched environment reduces hippocampal inflammatory response and improves cognitive function in a mouse model of stroke 被引量:1
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作者 Hong-Yu Zhou Ya-Ping Huai +7 位作者 Xing Jin Ping Yan Xiao-Jia Tang Jun-Ya Wang Nan Shi Meng Niu Zhao-Xiang Meng Xin Wang 《Neural Regeneration Research》 SCIE CAS CSCD 2022年第11期2497-2503,共7页
An enriched environment is used as a behavio ral intervention therapy that applies sensory,motor,and social stimulation,and has been used in basic and clinical research of va rious neurological diseases.In this study,... An enriched environment is used as a behavio ral intervention therapy that applies sensory,motor,and social stimulation,and has been used in basic and clinical research of va rious neurological diseases.In this study,we established mouse models of photothrombotic stroke and,24 hours later,raised them in a standard,enriched,or isolated environment for 4 weeks.Compared with the mice raised in a standard environment,the cognitive function of mice raised in an enriched environment was better and the pathological damage in the hippocampal CA1 region was remarkably alleviated.Furthermore,protein expression levels of tumor necrosis factor receptor-associated factor 6,nuclear factorκB p65,interleukin-6,and tumor necrosis factorα,and the mRNA expression level of tumor necrosis factor receptor-associated factor 6 were greatly lower,while the expression level of miR-146a-5p was higher.Compared with the mice raised in a standard environment,changes in these indices in mice raised in an isolated environment were opposite to mice raised in an enriched environment.These findings suggest that different living environments affect the hippocampal inflammatory response and cognitive function in a mouse model of stro ke.An enriched environment can improve cognitive function following stroke through up-regulation of miR-146a-5p expression and a reduction in the inflammatory response. 展开更多
关键词 cognitive function enriched environment isolated environment miR-146a-5p NEUROINFLAMMATION nuclear factorκB p65 photothrombotic model STROKE tumor necrosis factor receptor-associated factor 6
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Chemical Characteristic and Sensory Evaluation of Biscuit Enriched with Wheat Germ and the Effect of Storage Time on the Sensory Properties for this Product 被引量:1
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作者 Khaled M. Al-Marazeeq Malak M. Angor 《Food and Nutrition Sciences》 2017年第2期189-195,共7页
This work aimed at determining the maximum acceptable level of wheat germ that can be added to one of homemade biscuits in Jordan, studying some chemical and sensory properties of this product, moreover, studying the ... This work aimed at determining the maximum acceptable level of wheat germ that can be added to one of homemade biscuits in Jordan, studying some chemical and sensory properties of this product, moreover, studying the effect of storage time after two months at room temperature on the sensory parameters of this product. The results showed that the addition of wheat germ in biscuit making at level of 20% (w/w) enhanced the nutritional value by increasing protein and total mineral content, as well as decreasing fat, total carbohydrates and total calories. The acceptability of sensory characteristics was improved by this fortification immediately after preparation and during storage. 展开更多
关键词 BISCUIT WHEAT GERM enriched STORAGE TIME
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STATISTICAL ANALYSIS OF THE MATERIAL SOURCE AND THE MODERN SEDIMENTARY ENVIRONMENT OF THE FERROMANGANESE NODULES ENRICHED AREA OF THE NORTH PACIFIC REGION
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作者 鲍根德 杨谦宏 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 1990年第3期249-256,共8页
The source of elements and the modem sedimentary environment of the ferromanganese nodules enriched area of the North Pacific region were analysed statistically and discussed in detail - Cluster analysis shows the ar... The source of elements and the modem sedimentary environment of the ferromanganese nodules enriched area of the North Pacific region were analysed statistically and discussed in detail - Cluster analysis shows the area ’ s surface sediments are mainly brown clay and biogenic calcareous , calcsiliceous and siliceous ooze. Factor (principal component) analysis shows that the area’s trace elements (Fe . Mn.Cu】 Co.Ni 】 Zn , Cr . etc ) mainly come through adsorption of clay minerals and secondarily from authigenic sediments related to biochemical processes - 展开更多
关键词 SEDIMENTARY enriched NODULES modem MINERALS BIOCHEMICAL analysed CARBONATE BROWN favorable
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STUDY ON THE ACCUMULATION OF ENRICHED URANIUM UO_2F_2 IN SUBCELLULAR LEVEL BY ELECTRON MICROSCOPIC AUTORADIOGRAPHY
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作者 朱寿彭 汪源长 《Nuclear Science and Techniques》 SCIE CAS CSCD 1991年第1期35-41,共7页
In this paper we try to study the retentive peculiarity of soluble enriched uranium UO2F2 in subcellular level by electron microscopic autoradiography. The early dynamic accumulation of radioactivity in the body showe... In this paper we try to study the retentive peculiarity of soluble enriched uranium UO2F2 in subcellular level by electron microscopic autoradiography. The early dynamic accumulation of radioactivity in the body showed that enriched uranium UO2F2 was chiefly localized in kidney, especially accumulated in epicyte of kidney near- convoluted tubule. In liver cells, enriched uranium UO2F2 at first deposited in the nucleus and the cytoplasm, then accumulated in mitochondria selectively and lysosome as well. The electron microscopic autoradiographic study showed that the dynamic retention of radioactivity of enriched uranium UO2F2 in skeleton rose steadily throughout the exposure. Enriched uranium UO2F2 chiefly deposited in nucleus and mitochondria of the osteoblast as well as osteoclast. 展开更多
关键词 ELECTRON MICROSCOPIC AUTORADIOGRAPHY enriched uranium ULTRASTRUCTURE Nuclear emulsion ACCUMULATION
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TRANSFERENCE AND ACCUMULATIVE PECULIARITY OF ENRICHED URANIUM IN ORGANISM
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作者 朱寿彭 胡启跃 曹根发 《Nuclear Science and Techniques》 SCIE CAS CSCD 1993年第2期80-85,共6页
Studies show that 235UO2F2 was chiefly localized in kidneys, then in skeleton and liver. Its radioactivity in skeleton rose steadily while the concentration in kidneys and liver droped. 235UO2F2 was difficult to pass ... Studies show that 235UO2F2 was chiefly localized in kidneys, then in skeleton and liver. Its radioactivity in skeleton rose steadily while the concentration in kidneys and liver droped. 235UO2F2 was difficult to pass through the blood- testes barrier. With 1 to 6 h contact period, only 1.4-1.6 % 235UO2F2 was found in the intact skin, but 41-54 % in the abrasive skin. The dynamic retention of 235UO2F2 through intact or abrasive skins was also dominantly localized in kidneys, skeleton and liver. Accumulation of insoluble 235U3O8 in gastrointestinal tract was well described by a double- exponential- term expression. Values of retention were estimated for fast component T1= 0.34 d, and for relatively long term component T2= 4.05 d. 展开更多
关键词 TRANSFERENCE Accumulation enriched uranium Intact SKIN Abrasive SKIN TESTES
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INDUCTION OF MUTAGENIC EFFECT IN SOMATIC AND GERM CELLS BY ENRICHED URANIUM
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作者 朱寿彭 胡启跃 +1 位作者 曹根发 孙保福 《Nuclear Science and Techniques》 SCIE CAS CSCD 1993年第1期20-27,共8页
Enriched uranium(UO2F2) accumulated in organism could cause chromosome aberrations in somatic cells, its rates on bone marrow cells were elevated when the dose of 235UO2F2 was increased. Among the types of induced abe... Enriched uranium(UO2F2) accumulated in organism could cause chromosome aberrations in somatic cells, its rates on bone marrow cells were elevated when the dose of 235UO2F2 was increased. Among the types of induced aberrations, chromatid breakage was predominant, accompanied with a few chromosome breakage and translocation. At the same time mitosis index of metaphase cells was depressed. Chromatid delation and chromatid exchange were induced in peripheral blood lymphocytes. The important type of aberrations in spermatogonia was break. For primary spermatocytes the most significant aberration was multivalents which resulted either from chromatid interchanges or reciprocal translocations. 235UO2F2 could result in DNA breakage in germ cells. The sensitivity of germ cells at various stages to 235UO2F2. was different. At 12d after exposure the amount of sperm DNA eluted reached the peak. When the treating time was fixed, elution of sperm DNA from treated animals increased with the increasing doses. 235UO2F2. could also result in sperm abnormalities. Especially at 13 to 36 d after treatment the rates of sperm abnormalities were significantly elevated. 展开更多
关键词 enriched URANIUM SOMATIC CELLS GERM CELLS CHROMOSOME ABERRATIONS DNA Mutagenic effect
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Burnup optimization of once-through molten salt reactors using enriched uranium and thorium
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作者 Meng-Lu Tan Gui-Feng Zhu +5 位作者 Zheng-De Zhang Yang Zou Xiao-Han Yu Cheng-Gang Yu Ye Dai Rui Yan 《Nuclear Science and Techniques》 SCIE EI CAS CSCD 2022年第1期44-59,共16页
The advantages of once-through molten salt reactors include readily available fuel,low nuclear proliferation risk,and low technical difficulty.It is potentially the most easily commercialized fuel cycle mode for molte... The advantages of once-through molten salt reactors include readily available fuel,low nuclear proliferation risk,and low technical difficulty.It is potentially the most easily commercialized fuel cycle mode for molten salt reactors.However,there are some problems in the parameter selection of once-through molten salt reactors,and the relevant burnup optimization work requires further analysis.This study examined once-through graphitemoderated molten salt reactor using enriched uranium and thorium.The fuel volume fraction(VF),initial heavy nuclei concentration(HN_(0)),feeding uranium enrichment(E_(FU)),volume of the reactor core,and fuel type were changed to obtain the optimal conditions for burnup.We found an optimal region for VF and HN_(0) in each scheme,and the location and size of the optimal region changed with the degree of E_(FU),core volume,and fuel type.The recommended core schemes provide a reference for the core design of a once-through molten salt reactor. 展开更多
关键词 Once-through fuel cycle Molten salt reactor enriched uranium THORIUM
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The power of“touch”and early enriched stimulation:neuroplasticity effects in rodents and preterm infants
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作者 Alberto Fernández-Teruel 《Neural Regeneration Research》 SCIE CAS CSCD 2022年第6期1248-1250,共3页
Early postnatal stimulation,e.g.,neonatal handling(NH)in its most frequent form,and environmental enrichment(EE,the exposure of juvenile animals,usually during several weeks,to environments involving rich and variable... Early postnatal stimulation,e.g.,neonatal handling(NH)in its most frequent form,and environmental enrichment(EE,the exposure of juvenile animals,usually during several weeks,to environments involving rich and variable sensory stimulation)produce profound and long-lasting behavioral and neurobiological effects.Both treatments reduce anxiety and stress sensitivity,and improve neurodevelopment and learning/memory in unconditioned and conditioned tasks in laboratory rodents. 展开更多
关键词 STIMULATION NEONATAL enriched
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Selenium Enriched Trionyx sinensis : A New Choice for the Sustainable Development Model of Modern Agriculture
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作者 Bo YANG Wei HUANG +4 位作者 Xianghui QIN Jun YAN Chengde LIN Xiaofeng GAO Yinglan HUANG 《Agricultural Biotechnology》 CAS 2021年第6期62-63,78,共3页
Based on the analysis of the current situation and existing problems of traditional Chinese soft shelled turtle(Trionyx sinensis)breeding industry,combined with the fact that selenium enriched functional agriculture i... Based on the analysis of the current situation and existing problems of traditional Chinese soft shelled turtle(Trionyx sinensis)breeding industry,combined with the fact that selenium enriched functional agriculture is the future demand of mankind,this paper put forward the necessity of developing selenium enriched Chinese soft shelled turtles and promoting the sustainable development of modern agriculture:the development of selenium-enriched Chinese soft-shelled turtle is the need of the consumer market for food safety,the need to reduce the production cost of soft-shelled turtles and improve the production efficiency of soft-shelled turtles,the need to enrich the Chinese soft-shelled turtle market,and the need to promote the sustainable development of modern agriculture(fishery). 展开更多
关键词 Functional agriculture Selenium enriched Trionyx sinensis Modern agriculture Sustainable development of agriculture COUNTERMEASURE
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Simulation Studies of Diesel Engine Combustion Characteristics with Oxygen Enriched Air
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作者 Heng Wang Weijun Liu 《Journal of Power and Energy Engineering》 2015年第8期15-23,共9页
Based on a six-cylinder direct injection diesel engine, the engine operating condition was simulated by application AVL-FIRE software coupling the n-heptane reduced mechanism containing polycyclic aromatic hydrocarbon... Based on a six-cylinder direct injection diesel engine, the engine operating condition was simulated by application AVL-FIRE software coupling the n-heptane reduced mechanism containing polycyclic aromatic hydrocarbon (PAH) formation. The simulation and its verification test were both carried out under the maximum torque point. Then, the oxygen enriched combustion was simulated on the model, and the simulated condition was oxygen volume fraction from 21% to 30%. The simulation results show that, the oxygen enrichment (from 21% to 30%) increases the peak cylinder pressure of 3.32%, advances the start of combustion of 1.6 deg and rises the peak of average temperature in cylinder and wall heat flux. Among them, at the condition of 24% O2, the change of the results is the most significant. Benzene (A1) is one of the precursors of soot generated, the analysis of its impress-cuts of the mass distribution field in cylinder shows that, the increase of oxygen concentration can significantly inhibit the formation of benzene. But the oxygen enrichment makes the combustion more sufficient, cased a rise in the cylinder temperature, an extension in high temperature area, and an increment in the NOx emission. 展开更多
关键词 DIESEL Engine Numerical SIMULATION OXYGEN enriched COMBUSTION COMBUSTION CHARACTERISTIC
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Impact of Seasons on Soil Physico-Chemical Properties and Tea Yields Based on Enriched Sheep Manure Used in Kericho, Kenya
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作者 Rhoda Ruto Syphline Kebeney +1 位作者 John K. Bore David Chemei 《Journal of Agricultural Chemistry and Environment》 2019年第3期184-199,共16页
Tea (Camellia sinensis (L) O. Kuntze) is a perennial crop grown for beverage consumption. Its production is the leading foreign exchange earner in Kenya contributing about 26% foreign exchange and 4% GDP. Nitrogen (N)... Tea (Camellia sinensis (L) O. Kuntze) is a perennial crop grown for beverage consumption. Its production is the leading foreign exchange earner in Kenya contributing about 26% foreign exchange and 4% GDP. Nitrogen (N), Phosphorus (P) and potassium (K) are the recommended nutrients for tea production. However, their continuous use has been reported to have negative effect on soil physico-chemical properties and health. Sheep manure has been recommended in tea production for its soil pH buffering effect and increased tea yields. However, effects of sheep manure enriched with inorganic fertilizer on tea soils and yield have not been conclusively investigated. This study was established at KALRO—Tea Research Institute Kericho in Timbilil estate to determine the impact of seasonal variation on soil pysico-chemical properties and yields on enriched sheep manure used. Randomized complete block design (RCBD) experimental design was adopted with 14 treatments replicated thrice. The treatments were: control with no fertilizer use, NPK at 180 Kgs N/ha/yr, sheep manure only and two enriched sheep manure ratios of 4:1 and 8:1 which translates to a mixture of (4:1) 4 parts of sheep manure and 1 part of D.A.P inorganic fertilizer. Same applied to 8:1 ratio, respectively at rates of 60, 120, 180 and 240 Kgs N/ha once per year. Data were subjected to ANOVA in GenStat statistical package and means separated by Duncan’s multiple range tests at P ≤ 0.05 significance level. Results obtained showed that soil physico-chemical properties and tea yields were influenced significantly (P ≤ 0.05) by treatments applied. Soil available water and organic matter were higher on enriched sheep manure 4:1 at 240 rate used while soil porosity and bulk density were not significantly affected. Total N and P, increased with enriched sheep manure ratio of 4:1 at 240 rate while K+, Ca2+, Mg2+, Mn and pH increased with sole application of sheep manure at rate 180 and enriched sheep manure 8:1 at 180 rate. Tea yields increased with enriched sheep manure 4:1 ratios at the rates of 240. The findings recommend enriched sheep manure 4:1 ratio at 240 rates to be adopted by tea farmers within Kericho region. Further studies involving different geographical locations are proposed. 展开更多
关键词 SEASONS SOIL Physic-Chemical Properties enriched SHEEP MANURE Tea YIELDS
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Origin of enriched uranium contained in Japanese atmospheric deposits
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作者 Yoshikazu Kikawada Kohei Oda +4 位作者 Masao Nomura Teruyuki Honda Takao Oi Katsumi Hirose Yasuhito Igarashi 《Natural Science》 2012年第11期936-942,共7页
The chemical compositions of atmospheric deposits collected in Fukuoka, Japan, in 1964 and 2000, which are known to have high 235U/238U uranium isotope ratio were determined. High uranium contents relative to that of ... The chemical compositions of atmospheric deposits collected in Fukuoka, Japan, in 1964 and 2000, which are known to have high 235U/238U uranium isotope ratio were determined. High uranium contents relative to that of continental crust were observed for the deposition samples in 1964 together with the high 235U/238U ratios, which indicated that the origin of uranium is fallout materials due to the large-scale 1961- 1962 nuclear explosions conducted by US and former USSR. The deposits in 2000 were mainly composed of dusts from the East Asia. This suggested that uranium with a high 235U/238U ratio in the deposits in 2000 has been transported as a component of mineral dust particles contaminated with nuclear debris from nuclear test sites from the East Asian deserts and arid regions by the prevailing wind. 展开更多
关键词 ATMOSPHERIC DEPOSIT enriched URANIUM URANIUM ISOTOPE Ratio Nuclear Test ANTHROPOGENIC Radionuclides
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Effectiveness of Enriched Demonstration and Lecture Instructional Strategies on Senior Secondary School Students’Achievement in Chemistry
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作者 Lawrence Achimugu 《Journal of Contemporary Educational Research》 2018年第1期1-9,共9页
The study determined the relative effectiveness of enriched demonstration and lecture instructional strategies on senior secondary school students’achievement in Chemistry.To achieve this,two research questions and t... The study determined the relative effectiveness of enriched demonstration and lecture instructional strategies on senior secondary school students’achievement in Chemistry.To achieve this,two research questions and three hypotheses were formulated to guide the study.Quasi-experimental design:specifically the pre-test,post-test,nonequivalent and non-randomized control group was adopted for the study.A total sample of one hundred and sixty-six(166)SS 1 students,drawn using multistage sampling technique were used for the study.The instrument used for data collection was Chemistry Achievement Test(CAT,r=0.82).Mean and standard deviation were used to answer the research questions,while analysis of covariance(ANCOVA)was used to test the hypotheses.Findings from the study revealed that:there is significant difference between the achievement of students exposed to two enriched instructional strategies and those exposed to enriched traditional lecture strategy;there is no significant difference between male and female students exposed to the three modes of instructional strategies;and there is no significant interaction effect between the instructional strategies and gender.It was recommended that chemistry educators should focus attention on reforming or enriching the traditional instructional strategies and that chemistry teachers should particularly make use of the enriched demonstration strategy in their classroom interactions,among others. 展开更多
关键词 EFFECTIVENESS enriched DEMONSTRATION enriched LECTURE instructional strategy students’achievement in CHEMISTRY
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