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Steel Temperature Compensating Model With Multi-Factor Coupling Based on Ladle Thermal State 被引量:3
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作者 WU Peng-fei XU An-jun +1 位作者 TIAN Nai-yuan HE Dong-feng 《Journal of Iron and Steel Research International》 SCIE CAS CSCD 2012年第5期9-16,共8页
Combined with the parameters of the production process of a steel factory, numerical simulations for a new ladle from preheating to turnover are conducted using the finite element analysis system software (ANSYS). T... Combined with the parameters of the production process of a steel factory, numerical simulations for a new ladle from preheating to turnover are conducted using the finite element analysis system software (ANSYS). The measured data proved that the simulated results are reliable. The effects of preheating time, thermal cycling times, and empty package time on steel temperature are calculated, an ideal preheating time is provided, besides, based on the analysis of a single factor and use the nonlinear analysis method, a steel temperature compensating model with di- versified coupling factors is proposed, with the largest error of the present coupling model at 1. 462 ~C, and the er- rors between actual and target steel temperature in tundish after the model is applied to practical production are basi- cally controlled within -4-6 ~C, which can meet the accuracy of the manufacturer and has a practical guiding significance for the production in steelmaking workshops. 展开更多
关键词 LADLE thermal state multiple-factor coupling numerical simulation compensation model
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Estimation and Prediction of Bioconcentration Factors of Nonionic Organic Chemicals in Fish by Electrotopological State Indices and Structural Parameter 被引量:8
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作者 冯长君 杨伟华 沐来龙 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 北大核心 2008年第5期575-587,共13页
Based on the characteristics of atom types, Hall's electrotopological state indices (En) are calculated for 165 nonionic organic compounds. On the basis of the characteristics of substituent and conjugated matrix, ... Based on the characteristics of atom types, Hall's electrotopological state indices (En) are calculated for 165 nonionic organic compounds. On the basis of the characteristics of substituent and conjugated matrix, a novel molecular structure parameter (G) is defined and calculated for 165 molecules in this paper. En and G show good structural selectivity for organic molecules. G, a satisfactory relationship between bioconcentration factor (BCF) and En, is expressed as: 1gBCF = -0.283 + 1.246G + 0.079E42 + 0.351E9- 0.063E17 (n' = 122, R = 0.967, F = 425.636, s = 0.394), which could provide estimation and prediction for the lgBCF of nonionic organic chemicals. Furthermore, the model is examined to validate overall robustness with Jackknife tests, and the independent variables in model do not exist cross correlation with VIF. All these regression results show that the new parameter G and electrotopological state index have good rationality and efficiency. It is concluded that the En and G will be used widely in quantitative structure-property/activity relationship (QSPR/QSAR) research. 展开更多
关键词 nonionic organic compound bioconcentration factor electrotopologicai state index structure parameter QSAR
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Direct Calculation of Unsteady-State Weymouth Equations for Gas Volumetric Flow Rate with Different Friction Factors in Horizontal and Inclined Pipes 被引量:3
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作者 Abayomi O. Olatunde Tunde A. Adeosun +4 位作者 Mohammed A. Usman Olabisi M. Odunlami Moses A. Olowofoyeku Testy E. Ekakitie Atanda M. Mohammed 《Engineering(科研)》 2012年第4期202-209,共8页
Direct calculations of unsteady-state Weymouth equations for gas volumetric flow rate occur more frequently in the design and operation analysis of natural gas systems. Most of the existing gas pipelines design proced... Direct calculations of unsteady-state Weymouth equations for gas volumetric flow rate occur more frequently in the design and operation analysis of natural gas systems. Most of the existing gas pipelines design procedures are based on a particular friction factor and steady-state flow analysis. This paper examined the behavior of different friction factors and the need to develop model analysis capable of calculating unsteady-state gas flow rate in horizontal and inclined pipes. The results show different variation in flow rate with Panhandle A and Panhandle B attaining stability in accurate time with initial unsteadiness at the instance of flow. Chen and Jain friction factors have opposition to flow with high flow rate: The prediction also reveals that Colebrook-White degenerated to Nikuradse friction factor at high Reynolds number. The horizontal and inclined flow equations are considerably enhanced on the usage of different friction factors with the aid of Matlab to handle these calculations. 展开更多
关键词 Unsteady-state Flow Rate Friction factor Stability VARIATIONS UNSTEADINESS
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About Factorization of Quantum States with Few Qubits
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作者 G. V. López G. Montes +1 位作者 M. Avila J. Rueda-Paz 《Journal of Applied Mathematics and Physics》 2017年第2期469-480,共12页
Through the study of the factorization conditions of a wave function made up of two, three and four qubits, we propose an analytical expression which can characterize entangled states in terms of the coefficients of t... Through the study of the factorization conditions of a wave function made up of two, three and four qubits, we propose an analytical expression which can characterize entangled states in terms of the coefficients of the wave function and density matrix elements. 展开更多
关键词 ENTANGLED state factorized state DECOHERENCE Quantum Computing and Information Chain of SPINS System
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EFFECTS OF ACUPUNCTURE ON THE HIGH HEMAGGLUTINATION STATE, BLOOD-SUGAR-RAISING HORMONE AND IMMUNOCYTE FACTOR LEVELS IN TYPE-II DIABETES PATIENTS
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作者 谌剑飞 马雅玲 +2 位作者 蔡绍华 梁浩荣 沈晶 《World Journal of Acupuncture-Moxibustion》 2001年第4期12-17,共6页
Objective: To investigate the effect of acupuncture on high hemagglutination state, blood sugar raising hormone and immunocyte factor levels in type II diabetes patients. Methods: A total of 120 inpatients and outpati... Objective: To investigate the effect of acupuncture on high hemagglutination state, blood sugar raising hormone and immunocyte factor levels in type II diabetes patients. Methods: A total of 120 inpatients and outpatients were randomly divided into acupuncture plus medication group (n=52) and medication group (n=50). In addition, 18 type II diabetes patients formed acupuncture group for comparing their therapeutic effects. Main acupoints used were Pishu (BL 20), Geshu (BL 17), Yishu, Shenshu (BL 23), Zusanli (ST 36), Sanyinjiao (SP 6), etc.. combined with other acupoints according to different sydroms. These acupoints were stimulated by manipulaing the filiform needles with uniform reinforcing and reducing method for 15 min and then stimulated electrically for 15 min with an electroacupuncture therapeutic apparatus. Western medicines used were Glipizide, Dimethyldiguanide Hydrochloride, etc.. The treatment was given once daily, with 10 sessions being a therapeutic course, 2~3 courses altogether. Indexes of external thrombosis length (ETL), platelet agglutination rate (PAgR), fibrinogen (FG), activated partial thromboplastin time (APTT), fasting blood glucose (FBG), prothrombin time(PT), adrenocoticortropic hormone (ACTH), cortisol (CS), growth hormone (GH), glucagon (GL), tumor necrosis factor alpha (TNF α), interleukin 6 (IL 6), insulin (INS) and C peptide (C P) were determined using radioimmunoassay. Results: After 2~3 courses of treatment, both acupuncture group and medication plus acupuncture group could significantly improve high hemagglutination state, lower blood sugar raising hormone level, regulate immunocyte factor level and raise the sensitivity of insulin, which were apparently superior to those of medication group (P<0.05~0.01). Conclusion: Acupuncture therapy can effectively regulate plasma blood sugar raising hormone, immunocyte factor levels, increase the sensitivity of insulin to target cells, resist blood coagulation and improve microcirculation. 展开更多
关键词 Acupuncture therapy Type II diabetes High hemagglutination state Blood sugar raising hormone Immunocyte factors
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Seroprevalence of <i>Helicobacter pylori</i>Infection and Risk Factors among Asymptomatic Subjects in Delta State, Nigeria
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作者 Kingsley Ifeanyichukwu Omosor Omasan Herrienta Omosor +8 位作者 Isaiah Nnana Ibeh Babatunde Ishola Gabriel Adejumo Usman Itakure Abdulkadir Uchechukwu Dimkpa Gregory Ashimedua Uchuno Ojo Moses Oke Ramatu Lawal Abdulkadir Musa Vaima Hamidu Alaba Michael Emmanuel 《Advances in Microbiology》 2017年第9期641-652,共12页
Aim: The study aimed at evaluating the seroprevalence of H. pylori infection and its associated risk factors in a cross-section of asymptomatic adult population in Niger-Delta, Nigeria. Methodology: 408 apparently hea... Aim: The study aimed at evaluating the seroprevalence of H. pylori infection and its associated risk factors in a cross-section of asymptomatic adult population in Niger-Delta, Nigeria. Methodology: 408 apparently healthy volunteers, aged between 18 - 87 years were recruited for this study. Blood samples were collected from participants and analyzed for H. pylori antibody (IgG) qualitatively with Combo rapid kits and quantitatively with Accu-Bind ELISA Kits. Results: The overall prevalence of Helicobacter pylori colonization in 408 asymptomatic adults was 52.5% (n = 214) and 48.3% (n = 197) by qualitative (Combo rapid kits) and quantitative (Accu-Bind ELISA Kits) serological test methods respectively. H. pylori infection did not differ statistically between genders (p = 0.962) and among age groups (p = 0.185). In addition, multivariate logistic regression indicated that sex and age were not associated with risk of H. pylori. However, participants from Delta Central were at greater risk (OR = 1.89;p = 0.014) of H. pylori infection compared with those from Delta South, but those from Delta North were not at greater risk of infection compared with those from Delta South (p = 0.476). Conclusion: This study indicated an intermediate seroprevalence of H. pylori among asymptomatic adults in Delta state, Nigeria. The prevalence of H. pylori infection was linked to geographical regions but not with sex and age. 展开更多
关键词 Helicobacter pylori INFECTION Risk factors DELTA state NIGERIA
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Seroprevalence and Associated Risk Factors of Peste des Petits Ruminants among Sheep and Goats in Kassala State, Sudan
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作者 Fatima A. Saeed Sana A. Abdel-Aziz Mohammed M. Gumaa 《Open Journal of Animal Sciences》 2018年第4期381-395,共15页
Peste des petits ruminant (PPR) is a contagious disease of small ruminants caused by a virus that belongs to the genus Morbillivirus of the family Paramyxoviridae. This study aimed to determine the seroprevalence of P... Peste des petits ruminant (PPR) is a contagious disease of small ruminants caused by a virus that belongs to the genus Morbillivirus of the family Paramyxoviridae. This study aimed to determine the seroprevalence of PPR disease in sheep and goats and its associated risk factors in Kassala State, Eastern Sudan. Across sectional study was conducted during the period from 30th August to 25th November 2015. The study was carried out using a structured questionnaire survey and a total of 918 blood samples were collected from apparently healthy unvaccinated sheep and goats in different localities in State of Kassala. A total of 546 sheep and 372 goats were tested for specific antibodies to nucleoprotein (NP) by competitive enzyme linked immunosorbent assay (cELISA). The apparent overall prevalence of PPR antibodies in Kassala was 58.2% while the true prevalence was calculated to be 61.3%. The apparent prevalence in sheep and goats was 68.1% and 43.5% respectively. Univariate analysis showed that the risk factors had significant associations with a cELISA positive status: locality, species, age, breed, husbandry system, housing mode, animals movement (p = 0.000) and animals sharing pasture and water (p = 0.003), while sex and newly introduced animals were not significant risk factors (p = 0.771) (p = 0.050) respectively. Factors found that significantly associated (p < 0.05) with increased odds of being cELISA positive in multivariate analysis were localities, species, age and newly introduced animals. The prevalence differed between localities and was the highest in the River Atbara (84.0%) locality, whereas it was lowest in Delta North (29.0%). No significant difference was observed among the sexes. However, the prevalence differed in different age groups and was 52.25% in animals of less than six months old;49.3% were between seven months and two years old and 65.5% were above two years old. In different husbandry systems, the prevalence was 47.9%, 73.0% and 49.2% in intensive, open grazing and pastoral systems respectively. Housing type effects were also observed;the highest prevalence was in animals housed in metal fence (83.3%). The movement pattern showed significant effect, where the prevalence was the highest (81.3%) in animals that move inter-states/inter-localities. It is concluded that the disease is endemic in Kassala State, high prevalent in sheep and goats, posing a threat to animal exportation, and may have a serious economic influence. Owners and herders should compulsorily vaccinate their animals yearly and animals should be investigated periodically for implementation of crucial eradication program. 展开更多
关键词 Peste des Petits RUMINANTS SERO-PREVALENCE Risk factors Kassala state SUDAN
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Influencing factors and growth state classification of a natural Metasequoia population 被引量:3
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作者 Mu Liu Zhongke Feng +1 位作者 Chenghui Ma Liyan Yang 《Journal of Forestry Research》 SCIE CAS CSCD 2019年第1期337-345,共9页
By analyzing the importance of influencing factors and conducting a comparative study of the effects of different sorting algorithms, a new method is proposed that is suitable for classifying the growth state of a nat... By analyzing the importance of influencing factors and conducting a comparative study of the effects of different sorting algorithms, a new method is proposed that is suitable for classifying the growth state of a natural Metasequoia glyptostroboides Hu and W.C. Cheng population. We studied 2817 M. glyptostroboides trees over 100 years old and analyzed their growth state by measuring 15 factors from stumpage, site condition, and environmental data. The dimensionality of all factors were reduced using the random forest algorithm, and we classified the remaining factors using the following algorithms: random forest, back-propagation(BP) neural networks, and support vector machine(SVM). The applicability of each sorting algorithm was analyzed. When all the d factors are used for classification and modeling, the model's overall accuracy,kappa coefficient and test accuracy were 85.5%, 0.739 and 85.8%, respectively. By reducing the dimensionality of the factors using the random forest algorithm, 11 factors most strongly influenced the classifications of the growth state of the Metasequoia population: diameter at breast height,height, crown width, age from stumpage data; longitude,latitude, elevation, slope aspect, gradient and slope position from the site condition data; and the edge of the field from the environmental data. For classifying the Metasequoia population, the random forest algorithm has the highest overall accuracy at 87.2%, which is 3.4 and 2.3% higher than the BP neural networks and SVM algorithms,respectively. The SVM algorithm is superior to the random forest algorithm with respect to classifying the state of mortality. The combination of the random forest and SVM algorithms and their combined information can be used to classify and predict the growth state of this natural M.glyptostroboides population to provide a scientific basis for its effective protection. 展开更多
关键词 METASEQUOIA glyptostroboides GROWTH state RANDOM FOREST Support VECTOR machine(SVM) Influencing factor
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Latent Tuberculosis Infection among Household Contacts of Pulmonary Tuberculosis Cases in Central State, Sudan: Prevalence and Associated Factors
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作者 Abdulmannan Mohamed Aman Zeidan Abdu Zeidan 《Journal of Tuberculosis Research》 2017年第4期265-275,共11页
Introduction: Tuberculosis is a major health problem in developing countries including Sudan. Screening for TB cases through Household contacts (HHCs) investigation is an appropriate strategy to interrupt transmission... Introduction: Tuberculosis is a major health problem in developing countries including Sudan. Screening for TB cases through Household contacts (HHCs) investigation is an appropriate strategy to interrupt transmission of TB. Objectives: To determine the prevalence tuberculosis infection and risk factors for tuberculosis infection among household contacts in Wadimadani locality, Central State, Sudan, between November 2015 and April 2016. Methods: An analytical cross-sectional study conducted. During study period, to confirm TB diagnosis, all suspect contacts were tested through sputum samples, tuberculin skin test or chest X-ray. Structured questionnaire was used to collect socio-demographic and environmental factors. Results: One hundred forty six patients of smear-positive pulmonary tuberculosis were included in the study, 657 household contacts were identified and screened. Forty three new TB cases were detected from household contacts, yielding a prevalence of 6.5% (95% confidence interval = 0.05, 0.09) of latent tuberculosis infection (LTBI). Two factors were significantly associated with LTBI among HHCs: duration of contact with a TB patient ≤ 4 months (P = 0.03) and the educational status (P = 0.02). Conclusion: Screening of HHCs of index case of TB will contribute in early detection and treatment of new cases, and considered as a forward step towards eliminating TB. 展开更多
关键词 TUBERCULOSIS Latent TUBERCULOSIS Infection HOUSEHOLD Close Contact CENTRAL state SUDAN PREVALENCE Risk factors
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Non-Abelian Berry phase Factor of the Degenerate states
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作者 Wang Jianbo Shanxi Teacher’s University 《山西师范大学学报(自然科学版)》 1991年第4期30-35,共6页
Suppose the degenerate states wave function of a Hamitonian operatorHis accompanied by a natural phase factor, then we can own it to the role of sometransformation generator played by some non--degenerate Hermitian op... Suppose the degenerate states wave function of a Hamitonian operatorHis accompanied by a natural phase factor, then we can own it to the role of sometransformation generator played by some non--degenerate Hermitian operator containedin the complete set of conserved mechanical quantities. When this idea is extended tothe spece coordinated by parameters and the momentum--like operator is introduced,thenon-Abelian Berry phose factor of degenerate wave function can be easily gotter afterthe system evolves along a closed adiabatic curve. 展开更多
关键词 Degnerate state Non-Abelian BERRY PHASE factor
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Regulatory effect of vascular endothelial growth factor on blood spinal cord barrier in presyrinx state of experimental syringomyelia
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作者 Jianfeng Li Changrong Zhou +1 位作者 Haiying Liu Penghui Xing 《Neural Regeneration Research》 SCIE CAS CSCD 2008年第11期1181-1186,共6页
BACKGROUND: Vascular endothelial growth factor (VEGF) is able to regulate blood spinal cord barrier function as well as influence neovascularization and cause edema. OBJECTIVE: Through establishment of a rabbit mo... BACKGROUND: Vascular endothelial growth factor (VEGF) is able to regulate blood spinal cord barrier function as well as influence neovascularization and cause edema. OBJECTIVE: Through establishment of a rabbit model of syringomyelia, to explore the correlation between VEGF protein and mRNA expressions and function of blood spinal cord barrier and edema degree of spinal cord in presyrinx state. DESIGN, TIME AND SETTING: Randomized controlled animal study was performed in the Tumor Institute of the Fourth Hospital, Hebei Medical University from January to June 2007. MATERIALS: Atotal of 0.6 mL Kaolin solution (250 g/L, 37℃) was injected into the cisterna magna of 40 rabbits in the kaolin group to establish syringomyelia models. Goat anti-rabbit VEGF monoclonal antibody was provided by DIACLONE Company, USA; RT-PCR related reagents were provided by Huamei Bioengineering Co., Ltd., Beijing. METHODS: Sixty Chinese white rabbits were divided randomly into two groups: Kaolin group (n = 40) and control group (n = 20). Physiological saline (0.6 mL at 37℃) was injected in rabbits of control group. On days 1,3, 7, 14 and 21 after kaolin injection, cervical cords samples were harvested after sacrifice of animal. MAIN OUTCOME MEASURES: VEGF protein and mRNA expressions were detected by immunohistochemistry and RT-PCR on days 1, 3, 7, 14, and 21 after kaolin injection. A quantitative analysis of blood spinal cord barrier function was performed by Evans blue technique. Water content of the spinal cord was measured by dry-wet weight technique. The correlation between the expression of VEGF protein and mRNA and the function of blood spinal cord barrier in the upper cervical cord of the presyrinx state was analyzed by linear correlation analysis. RESULTS: The water content and Evans blue content increased in the kaolin group on days 1 and 3 postoperatively compared with the control group (F = 7.387, 61.35, P 〈 0.05, 0.01), and reached a peak on day 7 (F = 135.94, 528.35, P 〈 0.01). They declined slowly to day 21 postoperatively, but both contents were still higher than the control group (F = 11.51, 58.63, P 〈 0.01). VEGF protein expression increased on day 1, and stronger positive expression was seen on days 3, 7 and 14. It decreased on day 21. VEGF protein expression was higher than the control group at each time point (F = 137.4-468.5, P 〈 0.01 ). VEGF mRNA expression showed the same pattern in the cervical cord at different time points. By statistical analysis, the expression of VEGF protein and mRNA had a significantly positive correlation with the structural and functional changes of the blood spinal cord barrier in the presyrinx state (r = 0.604-0.979, P 〈 0.05). CONCLUSION: In the presyrinx state of syringomyelia, the expressions of VEGF protein and mRNA can influence the structure and function of the blood spinal cord barrier and play an important role in the formation and development of spinal cord edema and syringomyelia. 展开更多
关键词 presyrinx state blood spinal cord barrier vascular endothelial growth factor
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Barut-Girardello and Gilmore-Perelomov coherent states for pseudoharmonic oscillators and their nonclassical properties: Factorization method
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作者 M K Tavassoly H R Jalali 《Chinese Physics B》 SCIE EI CAS CSCD 2013年第8期421-428,共8页
In this paper we try to introduce the ladder operators associated with the pseudoharmonic oscillator, after solving the corresponding Schrrdinger equation by using the factorization method. The obtained generalized ra... In this paper we try to introduce the ladder operators associated with the pseudoharmonic oscillator, after solving the corresponding Schrrdinger equation by using the factorization method. The obtained generalized raising and lowering operators naturally lead us to the Dirac representation space of the system which is much easier to work with, in comparison to the functional Hilbert space. The SU(1, 1) dynamical symmetry group associated with the considered system is exactly established through investigating the fact that the deduced operators satisfy appropriate commutation relations. This result enables us to construct two important and distinct classes of Barut-Girardello and Gilmore-Perelomov coherent states associated with the system. Finally, their identities as the most important task are exactly resolved and some of their nonclassical properties are illustrated, numerically. 展开更多
关键词 pseudoharmonic oscillator factorization method Barut-Girardello coherent states Gilmore-Perelomov coherent states nonclassical properties
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Residues of High Concentration Carbendazim on Plants in Natural State
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作者 王凯全 周琪 +1 位作者 齐经济 乐林 《Plant Diseases and Pests》 CAS 2011年第5期48-51,共4页
[ Objective] The paper was to explore the residual dynamics and degradation rule of high concentration carbendazim in natural condition. [ Method J The earbendasim solutions with mass fractions of 0.2% ( recommended ... [ Objective] The paper was to explore the residual dynamics and degradation rule of high concentration carbendazim in natural condition. [ Method J The earbendasim solutions with mass fractions of 0.2% ( recommended concentration), 0.4% (2 times of the recommended concentration) and I. 0% (5 times of the recommended concentration) were sprayed on plant leaves, and the residual amount of earbendazim in natural condition was determined. The dynamic models of carbendazim residues Under 3 concentrations were also studied. [ Result~ The degradation of earbcndazim under recommended concentration was accorded with Kinetic model for degradation, but the degradation Kinetic model for samples under 2 times and 5 times concentration appeared dissimilation. The residue of carben- dazim on plant was affected by absorption capacity of plants and weather conditions. The absorption capacity was affected by application concentration and growth condition of plant, higher concentration application and slow growth stage of p]ant were not conducive to the absorption of carbendazim; weather condition was mainly referred to temperature and humidity, higher temperature and dry weather were not conducive to the degradation of earbendazim. [Condusion ] The paper provided theoretical basis for guiding the application of carbendazim under different growth stages of crops and different weather conditions in agricultural production. 展开更多
关键词 CARBENDAZIM Natural state RESIDUES Influence factors China
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中医药干预铁代谢紊乱治疗慢性肾脏病研究进展
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作者 温鑫雅 赵平 《河南中医》 2026年第1期156-162,共7页
无论是单味中药还是中药复方,都可以通过缓解促红细胞生成素(erythropoietin,EPO)缺乏、减轻炎症反应与改善缺氧状态,提高铁调素水平,靶向调节铁代谢,从而保护残余肾功能,延缓慢性肾脏病(chronic kidney disease,CKD)病情进展。不过,目... 无论是单味中药还是中药复方,都可以通过缓解促红细胞生成素(erythropoietin,EPO)缺乏、减轻炎症反应与改善缺氧状态,提高铁调素水平,靶向调节铁代谢,从而保护残余肾功能,延缓慢性肾脏病(chronic kidney disease,CKD)病情进展。不过,目前研究仍然存在一些不足:第一,现阶段对于中医药干预铁代谢防治CKD的作用机制研究较为浅显,今后可聚焦于中药核心成分及其相关分子通路等,解析中药调控铁代谢的分子网络,进一步阐明其作用机制。第二,目前疗效判定标准有待统一,今后可将现代医学指标与中医证候学特征相结合,制定统一规范的疗效评价标准。第三,个体化治疗的探索不足,缺乏对不同证型CKD患者铁代谢特征差异的系统研究。今后应建立中医药干预铁代谢的标准流程,将中医辨证论治充分融入现代研究中。 展开更多
关键词 慢性肾脏病 铁代谢紊乱 肾性贫血 促红细胞生成素 微炎症状态 低氧诱导因子 中医药
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THEORETICAL INVESTIGATION ON STATE OF LOAD DISTRIBUTION AMONG CONTACT BEARINGS OF DOUBLE CIRCULAR ARC HELICAL GEARS 被引量:3
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作者 Wu Baolin (Gear Research Institute, Taiyuan University of Technology) 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2000年第2期108-113,共6页
A dynamic analysis approcach to investigate the state of load distribution among contact bearings of double circular are belical gears is proposed and a computer program is developed for calculating the factor of iced... A dynamic analysis approcach to investigate the state of load distribution among contact bearings of double circular are belical gears is proposed and a computer program is developed for calculating the factor of iced distribution based on the theory of W-N gears. The changing situations of load distribution among contact bearings of the gears influenced by main issues are analyzed by a series of parametric studies. 展开更多
关键词 Double circular are belical gears state of load distribution factor of load distribution Dynamic analysis
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Preparation and control of atomic optimal entropy squeezing states for a moving two-level atom under control of the two-mode squeezing vacuum fields 被引量:2
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作者 周并举 刘一曼 +1 位作者 赵明卓 刘小娟 《Chinese Physics B》 SCIE EI CAS CSCD 2010年第12期278-284,共7页
From the viewpoint of quantum information, this paper studies preparation and control of atomic optimal entropy squeezing states (AOESS) for a moving two-level atom under control of the two-mode squeezing vacuum fie... From the viewpoint of quantum information, this paper studies preparation and control of atomic optimal entropy squeezing states (AOESS) for a moving two-level atom under control of the two-mode squeezing vacuum fields. Necessary conditions of preparation of the AOESS are analysed, and numerical verification of the AOESS is finished. It shows that the AOESS can be prepared by controlling the time of the atom interaction with the field, cutting the entanglement between the atom and field, and adjusting squeezing factor of the field. An atomic optimal entropy squeezing sudden generation in different components can alternately be realized by controlling the field-mode structure parameter. 展开更多
关键词 atomic optimal entropy squeezing state squeezing factor of the field the field-mode structure parameter
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Eutrophication development and its key regulating factors in a water-supply reservoir in North China 被引量:7
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作者 Liping Wang Lusan Liu Binghui Zheng 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2013年第5期962-970,共9页
Yanghe Reservoir is an important source of drinking water for Qinhuangdao City,North China;however,in recent decades this water source has been eutrophic with recurrent summer cyanobacterial blooms.The trophic grade o... Yanghe Reservoir is an important source of drinking water for Qinhuangdao City,North China;however,in recent decades this water source has been eutrophic with recurrent summer cyanobacterial blooms.The trophic grade of the system in summer was mesotrophiceutrophic in 1990 and became hypertrophic in 2011.The nutrient availability is extremely high during the entire year,and the water temperature should be the primary driver of the summer blooms.In May-October of 2010 and 2011,abrupt variations were observed in the Secchi depth(SD) and chlorophyll a(Chl-a),and both the correlated analysis of Chl-a-SD and trophic status indices(TSI) deviation(TSI Chl-a-TSI SD) showed that algal cell density dominated light attenuation.During the algal bloom outbreak,the microcystin concentration was found to vary between 0.35-2.12 μg/L in 2010 and 0.11-1.86 μg/L in 2011.The maximum microcystin content was more than two times the safety limit required for drinking water.Inflow discharges were most concentrated in the summer,with periods of lower residence time and the largest water level fluctuation over the entire year.When a high availability of nutrients promoted a high Chl-a concentration in the whole system,it appeared that the instability caused by the decrease in residence time could not produce effective changes in the cyanobacterial abundance.The results indicated that nutrient enrichment in the aquatic systems of Yanghe Reservoir is the most serious problem and that the status would not been modified effectively by increasing hydrological fluctuations(e.g.,decreasing the residence time).Therefore,decreasing the nutrient concentrations is the only route to improve the water quality of this reservoir. 展开更多
关键词 EUTROPHICATION trophic state cyanobacterial bloom limiting factors water-supply reservoir
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Study on the Relationship between Chlorophyll-a and Environmental Impact Factors in Deep Reservoir in Karst Areas——Taking Aha Reservoir for Example 被引量:2
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作者 XIA Pin-hua,LIN Tao,LI Cun-xiong,XUE Fei,ZHANG Bang-xi Key Laboratory of Mountainous Environmental Information System and Ecological Environment Protection in Guizhou Province,Guizhou Normal University,Guiyang 550001,China 《Meteorological and Environmental Research》 CAS 2011年第3期49-52,共4页
[Objective] The aim was to study the relationship between chlorophyll-a and environmental impact factors in deep reservoir in Karst Areas.[Method] Taking Aha Reservoir for example,the changes of chlorophyll-a content ... [Objective] The aim was to study the relationship between chlorophyll-a and environmental impact factors in deep reservoir in Karst Areas.[Method] Taking Aha Reservoir for example,the changes of chlorophyll-a content and its relationship with environmental impact factors were researched,and the water quality of Aha Reservoir was assessed by means of modified Carlson trophic state index.[Result] Chlorophyll-a content in Aha Reservoir was higher in March,April,May and September and lower from June to August,and there was obvious seasonal variation,namely its variation trend was spring>summer>autumn>winter.In addition,chlorophyll-a content showed extremely significant correlation with transparency and dissolved oxygen (P<0.01) and significant correlation with ammonia nitrogen (P<0.05).Meanwhile,trophic state index was higher in whole year in Aha Reservoir which was in moderate trophic state in August,October and November and eutrophic state in other months.[Conclusion] The study could provide scientific reference for discussing the mechanism of lake eutrophication. 展开更多
关键词 Aha Reservoir CHLOROPHYLL-A Environmental factors Trophic state index China
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中国式现代化、共同富裕与未来农业发展 被引量:3
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作者 倪国华 王政杰 《华中农业大学学报(社会科学版)》 北大核心 2025年第1期41-53,共13页
中国式现代化是全体人民共同富裕的现代化,促进共同富裕,最艰巨最繁重的任务仍然在农村。完成这项任务的关键环节是实现劳动生产率在不同农业门类之间以及农业与非农部门之间的趋同。独特的制度优势允许中国为实现上述趋同提前做好宏观... 中国式现代化是全体人民共同富裕的现代化,促进共同富裕,最艰巨最繁重的任务仍然在农村。完成这项任务的关键环节是实现劳动生产率在不同农业门类之间以及农业与非农部门之间的趋同。独特的制度优势允许中国为实现上述趋同提前做好宏观战略规划并不断推动微观布局向着上述趋同逼近,但是需要提前明确未来的均衡状态。从中国自身的特征出发,定量测算中国式现代化进程中土地和劳动力两大要素在不同农业门类之间以及农业与非农部门之间的流动潜能,量化估算未来农业发展的均衡状态。研究结果表明,为实现中国式现代化,必须推动高质量城镇化与经济结构转型双轮同步,同时合理引导资本和技术要素进入农业以补缺劳动力要素流出后的生产力水平下降。 展开更多
关键词 中国式现代化 共同富裕 农业发展 均衡状态 要素流动
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An accurate empirical correlation for predicting natural gas compressibility factors 被引量:2
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作者 Ehsan Sanjari Ebrahim Nemati Lay 《Journal of Natural Gas Chemistry》 EI CAS CSCD 2012年第2期184-188,共5页
The compressibility factor of natural gas is an important parameter in many gas and petroleum engineering calculations. This study presents a new empirical model for quick calculation of natural gas compressibility fa... The compressibility factor of natural gas is an important parameter in many gas and petroleum engineering calculations. This study presents a new empirical model for quick calculation of natural gas compressibility factors. The model was derived from 5844 experimental data of compressibility factors for a range of pseudo reduced pressures from 0.01 to 15 and pseudo reduced temperatures from 1 to 3. The accuracy of the new empirical correlation has been compared with commonly used existing methods. The comparison indicates the superiority of the new empirical model over the other methods used to calculate compressibility factor of natural gas with average absolute relative deviation percent (AARD%) of 0.6535. 展开更多
关键词 natural gas compressibility factor CORRELATION empirical model equation of state
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