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Effects of salinity on egg and fecal pellet production, development and survival, adult sex ratio and total life span in the calanoid copepod, A cartia tonsa:a laboratory study 被引量:1
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作者 SHAYEGAN Majid ESMAEILI FEREIDOUNI Abolghasem +1 位作者 AGH Naser JANI KHALILI Khosrow 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2016年第4期709-718,共10页
The ef fects of salinity on the copepod, A cartia tonsa in terms of daily egg production rate(EPR), hatching success, fecal pellet production rate(FPR), naupliar development time and survival, sex ratio, and total lif... The ef fects of salinity on the copepod, A cartia tonsa in terms of daily egg production rate(EPR), hatching success, fecal pellet production rate(FPR), naupliar development time and survival, sex ratio, and total life span were determined in laboratory conditions through three experiments. In experiment 1, EPR, hatching success, and FPR of individual females were monitored at salinities of 13, 20, 35 and 45 during short-periods(seven consecutive days). Results show EPR was aff ected by salinity with the highest outputs recorded at 20 and 35, respectively, which were considerably higher than those at 13 and 45. Mean FPR was also higher in 35 and 20. In experiment 2, the same parameters were evaluated over total life span of females(long-term study). The best EPR and FPR were observed in 35, which was statistically higher than at 13 and 20. In experiment 3, survival rates of early nauplii until adult stage were lowest at a salinity of 13. The development time increased with increasing of salinity. Female percentage clearly decreased with increasing salinity. Higher female percentages(56.7% and 52.2%, respectively) were signifi cantly observed at two salinities of 13 and 20 compared to that at 35(25%). Total longevity of females was not af fected by salinity increment. Based on our results, for mass culture we recommend that a salinity of 35 be adopted due to higher reproductive performances, better feeding, and faster development of A. tonsa. 展开更多
关键词 Acartia tonsa SALINITY egg and fecal pellet production sex ratio life span Caspian Sea
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SECONDARY CRITICAL EXPONENT AND LIFE SPAN FOR A DOUBLY SINGULAR PARABOLIC EQUATION WITH A WEIGHTED SOURCE
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作者 郑攀 穆春来 +1 位作者 胡学刚 张付臣 《Acta Mathematica Scientia》 SCIE CSCD 2016年第1期244-256,共13页
This paper deals with the Cauchy problem for a doubly singular parabolic equation with a weighted source ut=div|u|p-2um)+|x|α uq ,(x,t)∈RN×(0,t),where N ≥ 1, 1 〈 p 〈 2, m 〉 max(0,3 -p/N} satisfyi... This paper deals with the Cauchy problem for a doubly singular parabolic equation with a weighted source ut=div|u|p-2um)+|x|α uq ,(x,t)∈RN×(0,t),where N ≥ 1, 1 〈 p 〈 2, m 〉 max(0,3 -p/N} satisfying 2 〈 p+m 〈 3, q 〉 1, and(α 〉 N(3 - p - m) - p. We give the secondary critical exponent on the decay asymptotic behavior of an initial value at infinity for the existence and non-existence of global solutions of the Cauchy problem. Moreover, the life span of solutions is also studied. 展开更多
关键词 life span secondary critical exponent doubly singular parabolic equation weighted source BLOW-UP
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Existence and Life Span of Periodic Solutions for the First Order Quasilinear Hyperbolic Equations
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作者 王有安 王艳玲 《Chinese Quarterly Journal of Mathematics》 CSCD 1997年第3期87-94, ,共8页
In this paper the authors consider Cauchy problem of first order quasilinear hyperbolic and prove that existence of its periodic solutions and estimates of life span of solutions. This results reveals the relationship... In this paper the authors consider Cauchy problem of first order quasilinear hyperbolic and prove that existence of its periodic solutions and estimates of life span of solutions. This results reveals the relationship of dissipation and smoothness of periodic solutions. 展开更多
关键词 periodic solution DISSIPATION life span
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Performance Survey of PVC Insulation of LC/Gecamines Electrical Cables Subjected to Ageing and Its Life Span Evaluation
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作者 Chungu Mwana Mwamba Yannick Michael Kabangu Ngoie +4 位作者 Muliangala Mbalaba Francis Kasambay Mutangala Francis Katamea Mwanvua Mavé Twite Kabamba Edmond Lukozi Mufaume Donatien 《World Journal of Engineering and Technology》 2022年第4期728-737,共10页
Considering the insulators ageing in a mixture of PVC and dye, set following operating conditions and time to ensure proper operation and perfect safety of industrial installations using insulated conductors. The resu... Considering the insulators ageing in a mixture of PVC and dye, set following operating conditions and time to ensure proper operation and perfect safety of industrial installations using insulated conductors. The results showed that the insulation carried out by the L.C main office was a good quality (on thermal aspect), because the resistance of the insulation is so high (i.e. 3940 Mega Ohms under normal conditions). The results showed a lifespan of 50 years at a temperature of 40°C (close to ambient temperature), plus minus 33 years at a temperature of 70°C;plus minus 22 years at a temperature of 100°C and 12 years at a temperature of 160°C. Furthermore, information on chemical attack, the results showed that PVC cables have poor resistance to sulfuric acid attack (having a pH of 1.5 and a density of 1.84 g/cm<sup>3</sup>). LC/Gecamines is able to produce locally a good quality of electrical cables. 展开更多
关键词 PVC PERFORMANCE Thermal Ageing Chemical Resistance Cable life span
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Berberine Prolongs Life Span and Stimulates Locomotor Activity of <i>Drosophila melanogaster</i> 被引量:6
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作者 V. V. Navrotskaya G. Oxenkrug +1 位作者 L. I. Vorobyova P. Summergrad 《American Journal of Plant Sciences》 2012年第7期1037-1040,共4页
Drosophila melanogaster mutants with deficient kynurenine (KYN) formation from tryptophan (TRP) have longer life span than wild type flies. Administration of alpha-methyl-TRP and 5-methyl-TRY, the inhibitors of TRP-KY... Drosophila melanogaster mutants with deficient kynurenine (KYN) formation from tryptophan (TRP) have longer life span than wild type flies. Administration of alpha-methyl-TRP and 5-methyl-TRY, the inhibitors of TRP-KYN metabolism, prolonged life span in wild-type flies. Both inhibitors are not available for human use. Berberine, an isoquinoline alkaloid isolated from berberis aristata is known as the herb widely used in traditional Chinese and Indian medicine. Berberin is a strong inhibitor of the enzyme catalyzing TRP conversion into KYN. Considering this particular feature we investigated the effect of berberine on life-and health-span in wild-type Drosophila melanogaster. The results of our study showed that Berberine extended mean, median and maximum life span of female flies. Berberine did not affect the number of pupae of filial generation and decreased their lethality. Berberine increased locomotor activity (vertical climbing). The results of the study suggest that berberine prolongs life- and improves health-span of Drosophila melanogaster. Berberine might be a candidate drug for prevention and treatment of aging and aging-associated medical and psychiatric disorders. 展开更多
关键词 BERBERINE life span Drosophila MELANOGASTER KYNURENINE Vertical CLIMBING Viability
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Dietary <i>γ</i>-Aminobutyric Acid Shortens the Life Span of Stroke-Prone Spontaneously Hypertensive Rats
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作者 Nakamichi Watanabe Naomi Washio 《Food and Nutrition Sciences》 2011年第4期301-303,共3页
Dietary γ-amino butyric acid (GABA) has been suggested to decrease systolic blood pressure. This study aimed to ex-amine the effects of dietary GABA on the life span of stroke-prone spontaneously hypertensive rats (S... Dietary γ-amino butyric acid (GABA) has been suggested to decrease systolic blood pressure. This study aimed to ex-amine the effects of dietary GABA on the life span of stroke-prone spontaneously hypertensive rats (SHRSPs). In this study, life span was determined for SHRSPs provided 1% NaCl solution or 0.01% GABA in 1% NaCl solution as drinking water. The life span of the GABA-fed group (76.3 ± 1.65 days) was significantly shorter than that of the control group (81.6 ± 0.88 days). The results of this study may not be applicable to humans. Future studies will be necessary to elucidate the mechanism underlying this phenomenon. 展开更多
关键词 γ-Amino Butyric Acid Stroke-Prone Spontaneously HYPERTENSIVE Rat life span
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Effect and Mechanism of Ginsenoside Rg3 on Postoperative Life Span of Patients with Non-Small Cell Lung Cancer 被引量:28
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作者 路平 苏蔚 +3 位作者 苗战会 牛红蕊 刘晶 花勤亮 《Chinese Journal of Integrative Medicine》 SCIE CAS 2008年第1期33-36,共4页
Objective: To explore the effect and mechanism of ginsenoside Rg3 (Shenyi Capsule, 参一胶囊) on the postoperative life span of patients with non-small cell lung cancer (NSCLC). Methods: The prospective, randomiz... Objective: To explore the effect and mechanism of ginsenoside Rg3 (Shenyi Capsule, 参一胶囊) on the postoperative life span of patients with non-small cell lung cancer (NSCLC). Methods: The prospective, randomized, controlled method was adopted. One hundred and thirty- three patients with NSCLC were randomly assigned to 3 groups: Shenyi Capsule group (43 cases), combined therapy group (Shenyi Capsule plus chemotherapy, 46 cases), and chemotherapy group (44 cases). The survival rates, immune function and the correlation between vascular endothelial growth factor (VEGF) expression and clinical effect were analyzed in the three groups. Results: (1) The 1-year survival rate in the Shenyi group, the combined group and the chemotherapy group was 76.7% (33/43), 82.6% (38/46), and 79.5% (35/44), respectively; the 2-year survival rate was 67.4% (29/43), 71.7% (33/46), and 70.5% (31/44), respectively; and the 3-year survival rate was 46.5% (20/43), 54.3% (25/46), and 47.7% (21/44), respectively. There was no significant difference among the 3 groups (P〉0.05). (2) NK cells were increased to different degrees and the ratio of CD4/CD8 was normal in the Shenyi Capsule group and the combined group, while the ratio of CD4/CD8 was disproportional in the chemotherapy group. (3) In the chemotherapy group, the 3-year survival rate was lower in patients with positive expression of VEGF than in patients with negative expression (37.0% vs 64.7%, χ^2=17.9, P〈0.01), but no significant statistical difference was shown in the other two groups (53.6% vs 55.6%, P〉0.05; 44.4% vs 50.0%, P〉0.05). Conclusion: Shenyi Capsule, especially in combination with chemotherapy, can improve the life span of patients with NSCLC after operation. The mechanism might be correlated with improving the immune function and anti-tumor angiogenesis. 展开更多
关键词 non-small cell lung cancer Shenyi Capsule vascular endothelial growth factor life span
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Premature losses of leaf area in response to drought and insect herbivory through a leaf lifespan gradient
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作者 Sonia Mediavilla Montserrat Martínez-Ortega +2 位作者 Santiago Andrés Javier Bobo Alfonso Escudero 《Journal of Forestry Research》 SCIE CAS CSCD 2022年第1期39-50,共12页
Implications of the differences in leaf life span are still subject to debate in the field of ecophysiology.Since leaf traits associated with these differences may be decisive for determining the distribution of tree ... Implications of the differences in leaf life span are still subject to debate in the field of ecophysiology.Since leaf traits associated with these differences may be decisive for determining the distribution of tree species,this topic is particularly relevant in the context of climate change.This study analyzes the effects of the differences in leaf life span on premature losses of leaf area owing to insect herbivory and to abiotic stress.Loss of leaf area may be an important determinant of total leaf carbon assimilation.Seven Mediterranean tree species,distributed on four sites with different climates were studied.The species exhibited strong differences in leaf life span and in leaf traits,especially leaf mass per unit area.Premature leaf area losses were estimated in response to insect herbivory and summer drought over two years.The results revealed that,despite having older leaf cohorts with more damage,species with longer leaf duration had lower area lost to herbivores and less damage due to accelerated senescence during the summer drought.With respect to the predicted increase in water stress,deciduous species are at a disadvantage due to their high premature loss of leaf area and thus loss of photosynthetic capacity. 展开更多
关键词 Accelerated senescence Insect herbivory Leaf life span Leaf structural reinforcement Summer drought
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Effect on Life Span and Membrane Protein in Red Blood Cells by Integrated Medicine Therapy on Chronic Aplastic Anemia
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作者 王树庆 张圣明 李建华 《Chinese Journal of Integrative Medicine》 SCIE CAS 1998年第3期240-240,共1页
Objective: To explore the mechanism ofintegrated traditional Chinese and Westernmedicine (TCM--WM ) therapy on chronicaplastic anemia (CAA). Methods: The RBClife span of 30 normal human subjects and 30patients with CA... Objective: To explore the mechanism ofintegrated traditional Chinese and Westernmedicine (TCM--WM ) therapy on chronicaplastic anemia (CAA). Methods: The RBClife span of 30 normal human subjects and 30patients with CAA were measured by sir labelled technique before and after TCM--WMtherapy. The morphology and distribution ofRBC membrane protein granules were observed by freeze fracture etching and transmission electron microscope. Results: The halflife of erythrocytes (RBC TI/2)was shortenedin CAA cases and there was a significant difference compared to healthy control (P <0. 01). After therapy, the RBC life span prolonged and approached the normal level. Before treatment, there existed abnormal in morphology, decrease in amount and uneven indistribution of protein granules in protoplasmicface (PF) and extracellular face (EF) of RBCmembrane. After treatment, the protein granules of RBC membrane was improved and approached to control. Conclusions: The morphology, amount, quality and distribution ofRBC membrane protein granule were closelyrelated to its life span. The therapeutic effectof TCM--WM was better than that of WMalone and it had a function both in stabilizingmembrane protein and extending the RBC lifespan. 展开更多
关键词 Effect on life span and Membrane Protein in Red Blood Cells by Integrated Medicine Therapy on Chronic Aplastic Anemia
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Life Span of Solution to Cauchy Problem for a Semilinear Heat Equation
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作者 王明新 《Chinese Science Bulletin》 SCIE EI CAS 1993年第18期1497-1502,共6页
It is known that for 1【p【+∞, n=2 or 1【p【(n+2)/(n-2), n≥3, the elliptic problemhas a unique solution (x) which is radially symmetric and satisfies ’(0)=0, ’(r)【0, (x)~Me<sup>-α|x|<sup>... It is known that for 1【p【+∞, n=2 or 1【p【(n+2)/(n-2), n≥3, the elliptic problemhas a unique solution (x) which is radially symmetric and satisfies ’(0)=0, ’(r)【0, (x)~Me<sup>-α|x|<sup>2</sup></sup> as |x|→∞. Let u(x, t) be the solution (positive) ofIn Ref. [1| it has been proved that if λ】1, then u(x, t) blows up in finite time. We de- 展开更多
关键词 SEMILINEAR heat EQUATION BLOW up life span.
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Life-span of classical solutions for one-dimensional hydromagnetic flow
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作者 刘法贵 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2007年第4期511-520,共10页
The paper concerns Cauchy,problem for one-dimensional hydromagnetic dynamics with dissipative terms. When the dissipation coefficient is equal to zero it is shown that the smooth solutions develop shocks in the finite... The paper concerns Cauchy,problem for one-dimensional hydromagnetic dynamics with dissipative terms. When the dissipation coefficient is equal to zero it is shown that the smooth solutions develop shocks in the finite time if the initial amounts of entropy and magnetic field are smaller than those of sound waves; when it is larger than zero, and the initial amounts of entropyI this dissipation coefficient and the magnetic field in each period are smaller than those of sound Waves, then the smooth solutions blow up in the finite time. Moreover, the life-span of the smooth solution is given. 展开更多
关键词 hydromagnetic flow Cauchy' problem classical solution life-span
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LIFE-SPAN OF CLASSICAL SOLUTIONS TO HYPERBOLIC GEOMETRY FLOW EQUATION IN SEVERAL SPACE DIMENSIONS
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作者 孔德兴 刘琦 宋长明 《Acta Mathematica Scientia》 SCIE CSCD 2017年第3期679-694,共16页
In this article, we investigate the lower bound of life-span of classical solutions of the hyperbolic geometry flow equations in several space dimensions with "small" initial data. We first present some estimates on... In this article, we investigate the lower bound of life-span of classical solutions of the hyperbolic geometry flow equations in several space dimensions with "small" initial data. We first present some estimates on solutions of linear wave equations in several space variables. Then, we derive a lower bound of the life-span of the classical solutions to the equations with "small" initial data. 展开更多
关键词 Hyperbolic geometry flow classical solution life-span
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Analysis of Safe Span Length and Fatigue Life of Submarine Pipelines
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作者 HE Zhang-feng WEI Yuan LIU Shu-lin 《China Ocean Engineering》 SCIE EI CSCD 2020年第1期119-130,共12页
Owing to the complex environmental conditions, suspension could induce complicated forces on submarine pipelines and even cause vortex-induced vibration, resulting in fatigue damage of pipelines. Through aiming at the... Owing to the complex environmental conditions, suspension could induce complicated forces on submarine pipelines and even cause vortex-induced vibration, resulting in fatigue damage of pipelines. Through aiming at the 28-inch submarine pipeline in the East China Sea, the pipeline was segmented according to the similarity, considering the factors of pipe assembly, typhoon, current, wave and seabed topography. The effects of span length on natural frequency in each section of submarine pipeline were analyzed by finite element model. The maximum safe span length allowed by each pipeline section was verified by fatigue cumulative damage theory, and the fatigue life of each pipeline section were predicted. The results showed that each order natural frequency of the pipeline decreased with the increase of span length. The calculated results of empirical formulas were much smaller than those of the FEM analysis. The increase of the gap between the suspended pipeline and the seabed was beneficial to enhance the fatigue life of the suspended pipeline. 展开更多
关键词 submarine pipeline safe span length fatigue life vortex-induced vibration
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Life prediction and test period optimization research based on small sample reliability test of hydraulic pumps 被引量:5
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作者 郭锐 Ning Chao +4 位作者 Zhao Jingyi Wang Ping Shi Yu Zhou Jinsheng Luo Jing 《High Technology Letters》 EI CAS 2017年第1期63-70,共8页
Hydraulic pumps belong to reliable long-life hydraulic components. The reliability evaluation includes characters such as long test period,high cost,and high power loss and so on. Based on the principle of energy-savi... Hydraulic pumps belong to reliable long-life hydraulic components. The reliability evaluation includes characters such as long test period,high cost,and high power loss and so on. Based on the principle of energy-saving and power recovery,a small sample hydraulic pump reliability test rig is built,and the service life of hydraulic pump is predicted,and then the sampling period of reliability test is optimized. On the basis of considering the performance degradation mechanism of hydraulic pump,the feature information of degradation distribution of hydraulic pump volumetric efficiency during the test is collected,so an optimal degradation path model of feature information is selected from the aspect of fitting accuracy,and pseudo life data are obtained. Then a small sample reliability test of period constrained optimization search strategy for hydraulic pump is constructed to solve the optimization problem of the test sampling period and tightening end threshold,and it is verified that the accuracy of the minimum sampling period by the non-parametric hypothes is tested. Simulation result shows it could possess instructional significance and referenced value for hydraulic pump reliability life evaluation and the test's research and design. 展开更多
关键词 hydraulic pump small sample test volumetric efficiency degradation path model life span period optimal
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The Life Span of Classical Solutions to Nonlinear Wave Equations with Weighted Terms in Three Space Dimensions
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作者 Hu Sheng WANG Fan Lü 《Acta Mathematica Sinica,English Series》 SCIE 2024年第12期2984-3002,共19页
The paper considers the Cauchy problem with small initial values for semilinear wave equations with weighted nonlinear terms.Similar to Strauss exponent p0(n)which is the positive root of the quadratic equation 1+1/2(... The paper considers the Cauchy problem with small initial values for semilinear wave equations with weighted nonlinear terms.Similar to Strauss exponent p0(n)which is the positive root of the quadratic equation 1+1/2(n+1)p-1/2(n-1)p^(2)=0,we get smaller critical exponents p_(m)(n),p_(m)^(*)(n)and have global existence in time when p>p_(m)(n)or p>p_(m)^(*)(n).In addition,for the blow-up case,the introduction of the spacial weight shows the optimality of new upper and lower bound. 展开更多
关键词 Wave equation classical solution life span lower bound upper bound
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冷却速度对Thermo-Span合金组织和持久性能的影响 被引量:3
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作者 孙雅茹 于连旭 +3 位作者 孙文儒 孙晓峰 郭守仁 胡壮麒 《材料热处理学报》 EI CAS CSCD 北大核心 2010年第3期39-42,共4页
采用扫描电镜(SEM)、透射电镜(TEM)研究了固溶冷却速度对改型低膨胀Thermo-Span合金组织和持久性能的影响。结果表明:固溶冷却速度由空冷变为水冷,其它热处理条件不变,含0.05%B合金晶内析出γ′相的数量未见明显增多,而颗粒的尺寸变小,... 采用扫描电镜(SEM)、透射电镜(TEM)研究了固溶冷却速度对改型低膨胀Thermo-Span合金组织和持久性能的影响。结果表明:固溶冷却速度由空冷变为水冷,其它热处理条件不变,含0.05%B合金晶内析出γ′相的数量未见明显增多,而颗粒的尺寸变小,形态没有改变,晶界析出增多。合金650℃,600MPa的光滑持久性能保持较高水平,合金的缺口敏感性消失。 展开更多
关键词 Thermo-span合金 冷却速度 持久性能 缺口敏感
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Extension of Chronological Life in Saccharomyces cerevisiae under Ethanol Stress by Thermally Processed Rice Koji Extracts
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作者 Chizuru Yamaoka Osamu Kurita 《Advances in Microbiology》 2016年第9期575-589,共15页
The effect of thermally processed rice koji extracts on survival of yeast Saccharomyces cerevisiae was examined in comparison with non-heated koji extract. In chronological life span (CLS) tests on high-sugar fermenta... The effect of thermally processed rice koji extracts on survival of yeast Saccharomyces cerevisiae was examined in comparison with non-heated koji extract. In chronological life span (CLS) tests on high-sugar fermentation, the survivals of the yeast cells grown with heated koji extracts were higher than non-heated koji extract. Heat treatment of the extracts by autoclaving led to a loss in most of amino acids due to the Maillard reaction, although histidine contents slightly increased. In glucose-arginine mixtures, arginine was partly converted to histidine by autoclaving and the addition of histidine prolonged the CLS of yeast cells. The yeast cells grown with the non-heated extracts were more resistant to oxidative stress whereas the antioxidant activities were lower than those of the heated extracts. The yeast cells grown with the heated extracts were more tolerant to ethanol and had a higher reduction capacity in the late stationary phase when the cells were incubated in the presence of ethanol. Maillard reaction products elevated the levels of reactive oxygen species to yeast cells grown under ethanol stress in the late stationary phase. These results suggest that thermally processed koji extracts can act as a protectant against ethanol stress during the late stationary phase of yeast growth and extend the CLS due to the increase of histidine contents by autoclaving. 展开更多
关键词 Saccharomyces cerevisiae Koji Extracts life span Maillard Reaction HISTIDINE
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高温长期时效对改型低膨胀Thermo-Span合金热稳定性和性能的影响
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作者 孙雅茹 张代乐 +1 位作者 赵帅 于连旭 《材料热处理学报》 EI CAS CSCD 北大核心 2014年第9期6-10,共5页
研究了高温时效对标准和改型Thermo-Span合金组织和持久性能的影响,在650℃时效1000 h,标准合金的晶内与晶界Laves析出相均发生了粗化,而改型合金的析出相形貌没有改变,当时效温度增高到680℃时,标准合金在时效500 h时,合金的析出相已... 研究了高温时效对标准和改型Thermo-Span合金组织和持久性能的影响,在650℃时效1000 h,标准合金的晶内与晶界Laves析出相均发生了粗化,而改型合金的析出相形貌没有改变,当时效温度增高到680℃时,标准合金在时效500 h时,合金的析出相已经发生了严重的粗化,Laves相的形态由圆粒状变成条状,而改型合金的析出相没有变化,当时效到1000 h后,标准合金析出相已经完全粗化,析出相几乎布满了整个晶内,而改型合金晶界只有少量析出相开始发生粗化,经650℃时效1000 h后,改型合金具有较好的组织热稳定性,合金650℃/600 MPa的持久性能比标准合金高109 h。 展开更多
关键词 低膨胀Thermo-span合金 改型合金 时效 持久性能
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An empirical research on the field of wireless charging based on patent life length
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作者 施敏 Wang Juncheng +2 位作者 Zhou Xiaodan Hu Yiyuan Zhao Zelong 《High Technology Letters》 EI CAS 2018年第1期95-102,共8页
With the aid of patent life cycle theory,and from the perspective of patent life span,this paper choose the ‘times of citation-time sequence'data of patents as an observation index to research on related patents ... With the aid of patent life cycle theory,and from the perspective of patent life span,this paper choose the ‘times of citation-time sequence'data of patents as an observation index to research on related patents in the field of wireless charging by applying the adjusted ‘double-proportion'obsolescence method. The research reveals the rules of patent life span in the field of wireless charging,finding that the first 5 years since patents were authorized is the core period for the patents to play their full value,and also discovers the development law of merging technology patents. 展开更多
关键词 life span of PATENT PATENT information 'double-proportion' OBSOLESCENCE method
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具非局部源的伪抛物型方程的Cauchy问题
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作者 杨春晓 樊婕妤 吉飞宇 《纯粹数学与应用数学》 2024年第4期648-663,共16页
本文研究了具有非局部源的伪抛物型方程u_(t)=∆u+k∆ut+∥w(x)u∥_(Lq)^(p-1)(Rn)ur+1(x,t)的Cauchy问题,其中权函数w(x)∼|x|-s(当|x|足够大).在w(x)∈Lq和w(x)/∈L^(q)两种情况下考虑这一问题的第二临界指标,即鉴别整体解与非整体解的... 本文研究了具有非局部源的伪抛物型方程u_(t)=∆u+k∆ut+∥w(x)u∥_(Lq)^(p-1)(Rn)ur+1(x,t)的Cauchy问题,其中权函数w(x)∼|x|-s(当|x|足够大).在w(x)∈Lq和w(x)/∈L^(q)两种情况下考虑这一问题的第二临界指标,即鉴别整体解与非整体解的初值的临界衰减阶.结果表明,三阶粘性项k∆ut和权函数w(x)的存在有益于解的整体存在或可延迟解的爆破时间. 展开更多
关键词 伪抛物型方程 非局部源 临界衰减阶 第二临界指标 生命跨度
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