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Improving clinical outcomes of patients with hepatocellular carcinoma:Role of antiviral therapy,conversion therapy,and palliative therapy
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作者 Vishal G Shelat 《World Journal of Gastrointestinal Oncology》 SCIE 2024年第10期4037-4041,共5页
In this editorial,I comment on three articles published in the recent issue of the World Journal of Gastrointestinal Oncology.Hepatocellular carcinoma(HCC)is an important public health concern,and there are three arti... In this editorial,I comment on three articles published in the recent issue of the World Journal of Gastrointestinal Oncology.Hepatocellular carcinoma(HCC)is an important public health concern,and there are three articles on the theme of HCC in this issue.I focus on the articles by Mu et al,Chu et al,and Ma et al for this editorial.While these articles may be considered as low-quality evidence,and the results cannot be generalized to non-hepatitis-B or C virus patients,the discussion of the results is important.In addition,though all the articles are from China,the relevance of the results is not minuscule.As resection is the main form of curative treatment modality owing to a donor liver shortage,surgeons need to be aware that preoperative long-course antiviral therapy can improve clinical outcomes by reducing postoperative liver dysfunction and recurrence of HCC following resection.Similarly,patients with super-giant HCC(defined as≥15 cm diameter)should also be carefully considered for liver resection,and if it is unresectable upfront,then a combination of liver-directed therapy and systemic therapy may downstage HCC.If,following downstaging,the patient qualifies for liver resection based on locally prevalent resectability criteria,then such therapy is labelled as conversion(from unresectable to resectable)therapy.In unresectable patients treated by a combination of treatment options,serological markers like neutrophil-to-lymphocyte ratio and alpha-fetoprotein are reported to predict treatment responses,thus enabling personalized medicine. 展开更多
关键词 ANTIVIRALS CHEMOEMBOLIZATION conversion therapy Hepatocellular carcinoma Lenvatinib Neutrophil-to-lymphocyte ratio
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Intoxication Induced by Urea Containing Diets in Broiler Chickens: Effect on Weight Gain, Feed Conversion Ratio, Hematological and Biochemical Profiles
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作者 Mohammed Al-Zharani Mohammed Mubarak +2 位作者 Hassan Ahmed Rudayni Mahmoud M. Abdelwahab Mohammed Al-Eissa 《Advances in Bioscience and Biotechnology》 CAS 2023年第3期106-119,共14页
Urea as a source of cheap non-protein nitrogen is used to adulterate fish and meat meals which are basic components of broiler diets. The present study was carried out to elucidate the effects of urea on weight gain, ... Urea as a source of cheap non-protein nitrogen is used to adulterate fish and meat meals which are basic components of broiler diets. The present study was carried out to elucidate the effects of urea on weight gain, and hematological and biochemical profiles. A total of 48 broiler chicks were randomly allotted into 4 groups, designated Groups 1, 2, 3 and 4 of 12 birds each. Birds in Groups 2, 3 and 4 were fed on diets containing urea at the levels of 1%, 2.5% and 4%, respectively. Birds in Group 1 served as control and were not exposed to urea. Experimentation period was for 3 weeks and experiment was terminated when birds were 42 days of age. Body weight of all intoxicated birds at the various intervals was significantly decreased in comparison with that of the untreated control. Compared with control, all intoxicated broilers manifested significant (P ≤ 0.05) decrease in all hematological parameters involving erythrocytic and total leucocytic counts, Hemoglobin (Hb) and Packed Cell Volume (PCV) on a dose- and time-pattern. In comparison with the control levels, biochemical profile of the intoxicated birds disclosed significant decrease in blood glucose level and significant increase in serum uric acid, urea, Alkaline Phosphatase (ALP) and Lactate Dehydrogenase (LDH) levels. Based upon the present data, it was concluded that the addition of urea to broiler diets bears serious sequences concerning the general health condition, performance, weight gain, and hematological and biochemical profiles. 展开更多
关键词 UREA INTOXICATION Broiler Chickens Weight Gain Feed conversion ratio
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Model-based evaluation on the conversion ratio of ammonium to nitrite in a nitritation process for ammonium-rich wastewater treatment 被引量:4
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作者 LIXiao-ming YANGQi +4 位作者 ZENGGuang-ming A.Cornelius K.H.Rosenwinkel S.Kunst D.Weichgrebe 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2004年第6期1005-1010,共6页
Modeling for nitritation process was discussed and analyzed quantitatively for the factors that influence nitrite accumulation. The results indicated that pH, inorganic carbon source and Hydraulic Retention Time(HRT) ... Modeling for nitritation process was discussed and analyzed quantitatively for the factors that influence nitrite accumulation. The results indicated that pH, inorganic carbon source and Hydraulic Retention Time(HRT) as well as biomass concentration are the main factors that influenced the conversion ratio of ammonium to nitrite. A constant high pH can lead to a high nitritation rate and results in high conversion ratio on condition that free ammonia inhibition do not happen. In a CSTR system, without pH control, this conversion ratio can be monitored by pH variation in the reactor. The pH goes down far from the inlet level means a strongly nitrite accumulation. High concentration of alkalinity can promoted the conversion ratio by means of accelerating the nitritation rate through providing sufficient inorganic carbon source(carbon dioxide). When inorganic carbon source was depleted, the nitritation process stopped. HRT adjustment could be an efficient way to make the nitritation system run more flexible, which to some extent can meet the requirements of the fluctuant of inlet parameters such as ammonium concentration, pH, and temperature and so on. Biomass concentration is the key point, especially for a CSTR system in steady state, which was normally circumscribed by the characteristics of bacteria and may also affected by aeration mode and can be increased by prolonging the HRT on the condition of no nitrate accumulation when no recirculation available. The higher the biomass concentration is, the better the nitrite accumulation can be obtained. 展开更多
关键词 conversion ratio modeling analysis nitritation process nitrite accumulation
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Relation between soil matrix potential changes and water conversion ratios during methane hydrate formation processes in loess 被引量:1
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作者 Peng Zhang Qingbai Wu Guanli Jiang Yibin Pu 《Journal of Natural Gas Chemistry》 EI CAS CSCD 2011年第2期140-144,共5页
With a new apparatus designed and assembled by ourselves, the matrix potential of non-saturated loess was firstly measured and studied during methane hydrate formation processes. The experimental results showed that d... With a new apparatus designed and assembled by ourselves, the matrix potential of non-saturated loess was firstly measured and studied during methane hydrate formation processes. The experimental results showed that during two formation processes, the matrix potential changes of the loess all presented a good linear relationship with water conversion ratios. In addition, although it was well known that the secondary gas hydrate formation was easier than the initial, our experimental results showed that the initial hydrate formation efficiency in non-saturated loess was higher than that of the secondary. 展开更多
关键词 hydrate formation non-saturated loess matrix potential water conversion ratio
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Experimental Study on Conversion Characteristics of Dual-Mode OWC Models Appropriate for Voyaging
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作者 WU Bi-jun ZHANG Fu-ming +2 位作者 QIN Zi-zhen WU Heng-yu RAO Xiang 《China Ocean Engineering》 SCIE EI CSCD 2023年第2期247-257,共11页
Freely movable wave energy converters(WECs) will greatly improve their adaptability to the marine environment.In this paper, a dual-mode oscillating water column(OWC) WEC with potential sailing capability is proposed.... Freely movable wave energy converters(WECs) will greatly improve their adaptability to the marine environment.In this paper, a dual-mode oscillating water column(OWC) WEC with potential sailing capability is proposed. By opening and closing a gate on the side facing the waves, the WEC converts wave energy in the vertical duct(called VD mode) with low sailing resistance or in the backward bend duct(called BBD mode) with high sailing resistance.A small model and a medium model were designed and manufactured. The capture width ratio(CWR) of the small model in the two modes was experimentally studied. The CWR under bidirectional airflow and conversion characteristics under unidirectional airflow of the medium model in the BBD mode were obtained. Tests of the small model show that the peak CWR is 145.2% under regular waves and 90.1% under random waves in BBD mode, and in VD mode the peak CWR is about 60% of that in the BBD mode. Tests of the medium model show that the peak CWR is 228.96% under regular waves, the maximum wave-to-battery efficiency is 63.36% under regular waves and 30.17%under random waves, respectively. 展开更多
关键词 wave energy oscillating water column(OWC) capture width ratio(CWR) wave-to-battery conversion efficiency
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Study on the Relationships between Utilization Ratios and Conversion Rates of Nitrogen,Phosphorus and Potassium for Wheat
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作者 Zhiping HUANG Xianda HOU +6 位作者 Shutian LIU Shuojin WANG Hongyan ZHENG Jian DING Changhong MI Ling LU Yanlin HOU 《Meteorological and Environmental Research》 CAS 2020年第5期46-54,共9页
This paper studied the relationships between utilization ratios and conversion rates of nitrogen,phosphorus and potassium for wheat by data mining method based on data of"3414 fertilizer field trials"of whea... This paper studied the relationships between utilization ratios and conversion rates of nitrogen,phosphorus and potassium for wheat by data mining method based on data of"3414 fertilizer field trials"of wheat by published papers from national soil testing and recommendation since 2005.The results and conclusions were as follows:①the conceptual model of fertilizer utilization ratio of wheat for plot was that,Y N≈a+b×optimum nitrogen application amount+c×optimum fertilizer amount of K+d×rainfall in growth season,Y P≈a+b×optimum fertilizer amount of K+c×rainfall in growth season,Y K≈a+b×temperature in growth season+c×rainfall in growth season-d×optimum yield-e×optimum nitrogen application amount,respectively.②Fertilizer utilization ratio and nutrient conversion rate had 4 kinds of relationships.No significant relationships:13,of which 8 were soil nutrients,the results showed that soil nutrients had little effect on nutrient conversion rate and fertilizer utilization ratio;consistent significant relationships:4,they were all nitrogen and phosphorus,explaining the importance of nitrogen and phosphorus;contrary significant relationships:6,they were all nitrogen and phosphorus,illustrating that phosphorus and nitrogen had inhibitory effect;complementary significant relationships:31,the cause of the complementary phenomenon was that the fertilizer utilization ratio was the measuring index of fertilizer efficiency in one season,while the nutrient conversion rate was the measuring index of fertilizer efficiency in more seasons.It showed that the fertilizer utilization rate was significantly correlated,or the nutrient conversion rate was significantly correlated. 展开更多
关键词 Optimum yield Optimum fertilization amount Nutrient conversion rate Fertilizer utilization ratio Relative abundance-deficiency value of soil nutrient
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Study on the Relationship between Utilization Ratios and Conversion Rates of Nitrogen,Phosphorus and Potassium for Rice
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作者 Shuojin WANG Zhiping HUANG +6 位作者 Changhong MI Hongyan ZHENG Jian DING Shutian LIU Xianda HOU Ling LU Yanlin HOU 《Meteorological and Environmental Research》 CAS 2020年第5期25-32,共8页
This paper studied the relationships between utilization ratios and conversion rates of nitrogen,phosphorus and potassium for rice by data mining method based on data of"3414 fertilizer field trials"of rice ... This paper studied the relationships between utilization ratios and conversion rates of nitrogen,phosphorus and potassium for rice by data mining method based on data of"3414 fertilizer field trials"of rice by published papers from national soil testing and recommendation since 2005.The results and conclusions were as follows:①the conceptual model of fertilizer utilization ratio of rice for plot was that,Y N≈a+b×optimum yield+c×optimum fertilizer amount of K,Y P≈a+b×optimum yield,Y K≈a respectively.②Fertilizer utilization ratio and nutrient conversion rate had 4 kinds of relationships:①no significant relationships:25,of which 14 were soil nutrients and 9 were environmental factors,the results showed that soil nutrients and environmental factors had little effect on nutrient yield ratio and fertilizer utilization ratio;②consistent significant relationships:2,one was that yield ratio and utilization ratio of N were positively correlated with the optimum production,explaining the importance of N for production,the other was that yield ratio and utilization ratio of P had a significantly positive correlation with conversion rate and utilization ratio of N,illustrating that nitrogen and phosphorus had mutual promotion;③contrary significant relationships:5,these showed as negative correlations of fertilizer utilization ratio and positive correlation of nutrient conversion ratio;④complementary significant relationships:22,the cause of the complementary phenomenon was that the fertilizer utilization ratio was the index of fertilizer efficiency in one season,while the nutrient conversion rate was the index of fertilizer efficiency in more seasons,which showed that the fertilizer utilization rate was significantly correlated,or the nutrient conversion rate was significantly correlated. 展开更多
关键词 Optimum yield Optimum fertilization amount Nutrient conversion rate Fertilizer utilization ratio Relative abundance-deficiency value of soil nutrient
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Study on the Relationships between Utilization Ratios and Conversion Rates of Nitrogen,Phosphorus and Potassium for Maize
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作者 Hongyan ZHENG Ling LU +6 位作者 Xianda HOU Shuojin WANG Zhiping HUANG Jian DING Changhong MI Shutian LIU Yanlin HOU 《Meteorological and Environmental Research》 CAS 2020年第5期69-75,90,共8页
This paper studied the relationships between utilization ratios and conversion rates of nitrogen,phosphorus and potassium for maize by data mining method based on data of"3414 fertilizer field trials"of maiz... This paper studied the relationships between utilization ratios and conversion rates of nitrogen,phosphorus and potassium for maize by data mining method based on data of"3414 fertilizer field trials"of maize by published papers from national soil testing and recommendation since 2005.The results and conclusions were as follows:①the conceptual model of fertilizer utilization ratio of maize for plot was that,Y N≈a+b×optimum yield,Y P≈a+b×optimum yield-c×optimum nitrogen application amount-d×optimum potassium application amount,Y K≈a-b×optimum nitrogen application amount-c×temperature in growth season-d×rainfall in growth season,respectively.②Fertilizer utilization ratio and nutrient conversion rate had 4 kinds of relationships.No significant relationships:22,of which 16 were soil nutrients and 5 were environmental factors,the results showed that soil nutrients and environmental factors had little effect on nutrient conversion rate and fertilizer utilization ratio;consistent significant relationships:14,illustrating that conversion rate and utilization ratio of maize were consistent in most cases,and it was because that maize was planted for a long term,and its fertilizer absorption law was basically stable;contrary significant relationships:0,illustrating that there was no reverse relationship between conversion rate and utilization ratio of maize;complementary significant relationships:18,the cause of the complementary phenomenon was that the fertilizer utilization ratio was the measuring index of fertilizer efficiency in one season,while the nutrient conversion rate was the measuring index of fertilizer efficiency in more seasons.It showed that the fertilizer utilization ratio was significantly correlated,or the nutrient conversion rate was significantly correlated. 展开更多
关键词 Optimum yield Optimum fertilization amount Nutrient conversion rate Fertilizer utilization ratio Relative abundance-deficiency value of soil nutrient
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Oscillation and Conversion Performance of Double-Float Wave Energy Converter 被引量:4
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作者 Liang Zhang Peng Jin +2 位作者 Binzhen Zhou Xiongbo Zheng Hengxu Liu 《Journal of Marine Science and Application》 CSCD 2019年第1期54-63,共10页
In this study, we investigated the hydrodynamic and energy conversion performance of a double-float wave energy converter(WEC) based on the linear theory of water waves. The generator power take-off(PTO) system is mod... In this study, we investigated the hydrodynamic and energy conversion performance of a double-float wave energy converter(WEC) based on the linear theory of water waves. The generator power take-off(PTO) system is modeled as a combination of a linear viscous damping and a linear spring. Using the frequency domain method, the optimal damping coefficient of the generator PTO system is derived to achieve the optimal conversion efficiency(capture width ratio).Based on the potential flow theory and the higher-order boundary element method(HOBEM), we constructed a threedimensional model of double-float WEC to study its hydrodynamic performance and response in the time domain. Only the heave motion of the two-body system is considered and a virtual function is introduced to decouple the motions of the floats. The energy conversion character of the double-float WEC is also evaluated. The investigation is carried out over a wide range of incident wave frequency. By analyzing the effects of the incident wave frequency, we derive the PTO's damping coefficient for the double-float WEC's capture width ratio and the relationships between the capture width ratio and the natural frequencies of the lower and upper floats. In addition, it is capable to modify the natural frequencies of the two floats by changing the stiffness coefficients of the PTO and mooring systems. We found that the natural frequencies of the device can directly influence the peak frequency of the capture width, which may provide an important reference for the design of WECs. 展开更多
关键词 Double-float WEC Energy conversion CAPTURE WIDTH ratio Optimal damping Resonance
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In situ catalytic conversion of biomass fast pyrolysis vapors on HZSM–5 被引量:3
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作者 Yindi Zhang Ping Chen Hui Lou 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2016年第3期427-433,共7页
In situ catalytic conversion of biomass fast pyrolysis vapors was carried out on HZSM-5 with varying Si/Al ratios(ranging from 20 to 300) at 450 °C. The effects of Si/Al ratios of HZSM-5 zeolites on the distribut... In situ catalytic conversion of biomass fast pyrolysis vapors was carried out on HZSM-5 with varying Si/Al ratios(ranging from 20 to 300) at 450 °C. The effects of Si/Al ratios of HZSM-5 zeolites on the distribution of biomass fast pyrolysis products and carbon deposits on catalysts were investigated. It was quite remarkable that after in situ catalytic conversion the amount of light phenols and hydrocarbons increased significantly while that of heavy phenols decreased a lot. Besides, the yield of cyclopentenones with relatively low oxygen content generally increased. It also indicated that as the Si/Al ratios of HZSM-5 increased, the amount of hydrocarbons and light phenols was found to drop greatly. The amount of carbon deposits was found to be around 8.5% with the exception of HZSM-5 with the Si/Al ratio of 300,which is much lower. Moreover, the carbon deposits yield dropped gradually with increasing Si/Al ratios of HZSM-5.Calcination of spent catalysts at 600 °C helped to restore the catalytic activity to a large extent despite a relatively lower efficiency of deoxygenation. Results indicated that HZSM-5 with relatively high acidity displayed great catalytic performance. 展开更多
关键词 Fast pyrolysis In situ catalytic conversion HZSM-5 Si/Al ratio Carbon deposits
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Hydrodynamic Analysis and Power Conversion for Point Absorber WEC with Two Degrees of Freedom Using CFD 被引量:2
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作者 GUO Wei ZHOU Ya-hui +1 位作者 ZHANG Wan-chao ZHAO Qiao-sheng 《China Ocean Engineering》 SCIE EI CSCD 2018年第6期718-729,共12页
Point absorber wave energy device with multiple degrees of freedom(DOF) is assumed to have a better absorption ability of mechanical energy from ocean waves. In this paper, a coaxial symmetric articulated point absorb... Point absorber wave energy device with multiple degrees of freedom(DOF) is assumed to have a better absorption ability of mechanical energy from ocean waves. In this paper, a coaxial symmetric articulated point absorber wave energy converter with two degrees of freedom is presented. The mechanical equations of the oscillation buoy with power take-off mechanism(PTO) in regular waves are established. The three-dimensional numerical wave tank is built in consideration of the buoy motion based upon the CFD method. The appropriate simulation elements are selected for the buoy and wave parameters. The feasibility of the CFD method is verified through the contrast between the numerical simulation results of typical wave conditions and test results. In such case, the buoy with single DOF of heave, pitch and their coupling motion considering free(no PTO damping) and damped oscillations in regular waves are simulated by using the verified CFD method respectively. The hydrodynamic and wave energy conversion characteristics with typical wave conditions are analyzed. The numerical results show that the heave and pitch can affect each other in the buoy coupling motion, hydrodynamic loads, wave energy absorption and flow field.The total capture width ratio with two coupled DOF motion is higher than that with a single DOF motion. The wave energy conversion of a certain DOF motion may be higher than that of the single certain DOF motion even though the wave is at the resonance period. When the wave periods are high enough, the interaction between the coupled DOF motions can be neglected. 展开更多
关键词 CFD simulation wave energy conversion numerical tank coupling motion capture width ratio
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Green and red up-conversion emissions and thermometric application of Er^(3+) -doped silicate glass 被引量:3
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作者 李成仁 董斌 +1 位作者 李磊 雷明凯 《Chinese Physics B》 SCIE EI CAS CSCD 2008年第1期224-227,共4页
The green and red up-conversion emissions centred at about 534, 549 and 663 nm of wavelength, corresponding respectively to the ^2H11/2 → ^4I15/2, ^4S3/2 → ^4I15/2 and ^4F9/2 → ^4I15/2 transitions of Er^3+ ions, h... The green and red up-conversion emissions centred at about 534, 549 and 663 nm of wavelength, corresponding respectively to the ^2H11/2 → ^4I15/2, ^4S3/2 → ^4I15/2 and ^4F9/2 → ^4I15/2 transitions of Er^3+ ions, have been observed for the Er^3+-doped silicate glass excited by a 978 nm semiconductor laser beam. Excitation power dependent behaviour of the up-conversion emission intensity indicates that a two-photon absorption up-conversion process is responsible for the green and red up-conversion emissions. The temperature dependence of the green up-conversion emissions is also studied in a temperature range of 296-673 K, which shows that Er^3+-doped silicate glass can be used as a sensor in high-temperature measurement. 展开更多
关键词 Er^3+-doped silicate glass up-conversion emission fluorescence intensity ratio
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Studies on Conversion of K in Potash Feldspar into Water-soluble Form
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作者 李华 范秀山 +1 位作者 王光龙 刘大壮 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2001年第4期447-450,共4页
The studies for raising potash feldspar utilization ratio by physical, biological and chemical methods are carried out in laboratory and the results are presented. It is shown that calcinatory and biological methods h... The studies for raising potash feldspar utilization ratio by physical, biological and chemical methods are carried out in laboratory and the results are presented. It is shown that calcinatory and biological methods have positive effects on conversion of K in potash feldspar into water-soluble form, but the conversion is low; chemical method can change most of insoluble potassium into available form, and might be significant in industry to some extent. 展开更多
关键词 potash feldspar conversion ratio biological method physical method chemical method
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Experimental Investigation of Multi-Mode Vortex-Induced Vibration of Flexible Risers with Different Mass Ratios
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作者 WANG Yu LOU Min +3 位作者 REN Xiao-hui LIANG Wei-xing LI Xiang DANG Peng-bo 《China Ocean Engineering》 SCIE EI CSCD 2023年第1期1-15,共15页
Experiments were conducted on risers with different mass ratios to study the effect of mode conversion and spanwise correlation. The slenderness ratio of the riser model was set as 169, and the Reynolds numbers are 16... Experiments were conducted on risers with different mass ratios to study the effect of mode conversion and spanwise correlation. The slenderness ratio of the riser model was set as 169, and the Reynolds numbers are 1600-14400. The dynamic responses of riser models versus reduced velocity were analyzed, and the spanwise displacement, frequency,and trajectory of the mode conversion from the lower to the higher mode were explored. The results revealed that the riser model with a higher mass ratio excites a higher number of modes. The conversion region of multi-mode competition exists and narrows with the increasing mass ratio. Mode conversion is continuous and manifests as the transmission of peaks and troughs in mode shape: the peaks and troughs of mode shape move up in the mode stable development region and move down in the mode conversion region. The single-mode dominating vibration exhibits a standing wave feature, and the traveling wave feature is significant in the mode conversion region. Furthermore, the frequency jump is always transmitted from the trough to the peak of the mode shape, and finally, all the axial positions vibrate at the same frequency. The trajectory in the mode conversion region deviates from the 8-shape and recovers the standard8-shape at the middle and late stages of the mode stable development region. 展开更多
关键词 vortex-induced vibration dynamic response mode conversion mass ratio mode weight
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Influence of fish meal quality on growth,feed conversion rate and protein digestibility in shrimp (Penaeus chinensis ) and red seabream (Pagrosomus major)
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作者 梁明青 AndersAksnes 《海洋水产研究》 CSCD 2001年第4期75-79,共5页
The effect of fishmeal quality on growth,feed conversion ratio and protein digestibility was studied in a growth experiment with shrimp and red seabream.The shrimp and fish were fed three diets varing in the quality o... The effect of fishmeal quality on growth,feed conversion ratio and protein digestibility was studied in a growth experiment with shrimp and red seabream.The shrimp and fish were fed three diets varing in the quality of the fishmeal used in the respective feeds: low quality fish meal,good quality fish meal,and Peru fish meal.The experiment lasted for 2 months.The shrimp and fish fed the feed with good quality fish meal showed significantly better feed conversion ratio,weight gain rate,protein digestibility than the other groups. 展开更多
关键词 鱼粉质量 中国对虾 真鲷 饲料转化率 蛋白质 消化率 对虾
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一种低转换比且效率超90%的混合式转换器
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作者 任建 臧勃安 华晨杰 《电力电子技术》 2024年第10期12-14,30,共4页
针对低转换比降压转换器的需求,提出了一种三电流通路(3CP)混合式电压转换器,并且为了提高轻载下转换器的转换效率,提出了一种轻重负载下的工作模式切换方法。由此实现了在低电压转换比的应用场景下,在全负载范围内均实现高转换效率:采... 针对低转换比降压转换器的需求,提出了一种三电流通路(3CP)混合式电压转换器,并且为了提高轻载下转换器的转换效率,提出了一种轻重负载下的工作模式切换方法。由此实现了在低电压转换比的应用场景下,在全负载范围内均实现高转换效率:采用提出的方法,实现了一款基于CSMC180工艺的混合式DC/DC降压型转换器,其中输入电压为5 V,输出电压为0.6V,带负载能力为1 A。实验结果显示,应用此方法的转换器的峰值转换效率可超过90%。 展开更多
关键词 混合式转换器 低电压转换比 三电流通路
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沸腾床渣油加氢裂化装置投产对重油制氢装置的影响
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作者 严钧 《大氮肥》 CAS 2024年第4期237-240,共4页
沸腾床渣油加氢裂化装置投产后,将溶剂脱沥青装置的原料由常减压装置洗涤油和减压渣油调整为渣油加氢裂化装置未转化油,作为重油制氢装置原料的脱油沥青性质由此发生变化。对比重油制氢装置原料油性质、主要操作参数、技术经济指标、气... 沸腾床渣油加氢裂化装置投产后,将溶剂脱沥青装置的原料由常减压装置洗涤油和减压渣油调整为渣油加氢裂化装置未转化油,作为重油制氢装置原料的脱油沥青性质由此发生变化。对比重油制氢装置原料油性质、主要操作参数、技术经济指标、气化炉运行周期等参数,结果表明,渣油加氢裂化装置投产后,以脱油沥青为原料的重油制氢装置气化炉油气分布更均匀,气化单元有效气含量提高2.12个百分点,有效气产率提高0.20个百分点,碳转化率提高0.18个百分点,氢气产率提高1.21个百分点,吨氢标油能耗下降140 kg,装置各项技术经济指标均有较大幅度提升,气化炉烧嘴运行周期明显延长。 展开更多
关键词 沸腾床渣油加氢裂化 重油制氢 溶剂脱沥青 脱油沥青 气化炉 氢气 碳转化率
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畜禽饲料效率性状遗传研究进展
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作者 范悦 韩博 +3 位作者 李艳华 刘林 麻柱 孙东晓 《畜牧兽医学报》 CAS CSCD 北大核心 2024年第7期2786-2794,共9页
饲料效率是评价畜牧生产效率高低的一项重要指标,它是畜禽育种研究的重要性状之一。在过去几十年里,肉蛋奶产量等畜禽生产性状已经取得显著遗传进展。随着饲料成本的逐年提高,近几年饲料效率性状逐渐受到育种工作者的高度关注。欧美国... 饲料效率是评价畜牧生产效率高低的一项重要指标,它是畜禽育种研究的重要性状之一。在过去几十年里,肉蛋奶产量等畜禽生产性状已经取得显著遗传进展。随着饲料成本的逐年提高,近几年饲料效率性状逐渐受到育种工作者的高度关注。欧美国家已陆续将饲料效率作为育种目标纳入综合选择指数,我国也开始相关研究并取得了研究进展。本文介绍了饲料效率的概念、常用衡量指标、遗传参数估计,并综述了国内外常见畜禽饲料效率性状的研究进展,为进一步解析畜禽饲料效率性状遗传机制和优化育种方案提供参考。 展开更多
关键词 饲料效率 饲料转化率 剩余采食量 遗传参数
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北京鸭对博落回散的耐受性试验
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作者 姚开兰 董朕 +4 位作者 石达友 李长虹 唐昭山 曾建国 柳亦松 《黑龙江畜牧兽医》 CAS 北大核心 2024年第7期112-118,124,共8页
为了探究北京鸭对博落回散的耐受性,为博落回散在饲料中的安全添加剂量提供数据支持,试验将210只1日龄北京鸭分为5组,对照组饲喂不添加任何药物的基础日粮,30,90,150,300 mg/kg组分别饲喂含30,90,150,300 mg/kg博落回散的基础日粮,连续... 为了探究北京鸭对博落回散的耐受性,为博落回散在饲料中的安全添加剂量提供数据支持,试验将210只1日龄北京鸭分为5组,对照组饲喂不添加任何药物的基础日粮,30,90,150,300 mg/kg组分别饲喂含30,90,150,300 mg/kg博落回散的基础日粮,连续饲喂42 d,分别在14,28,42日龄早晨投料前称量北京鸭的体重,测定各组鸭在1~14、15~28、29~42、1~42日龄的生长性能;分别在14,28,42日龄采集血液,测定各组血常规与血清生化指标;42日龄时屠宰各组北京鸭,采集器官测定器官指数,进行病理解剖并观察组织病理学变化,评价北京鸭对不同剂量博落回散的耐受性。结果表明:与对照组相比,30,90,150 mg/kg组1~42日龄间的日增重和饲料转化率显著提高(P<0.05),300 mg/kg组呈下降趋势但差异不显著(P>0.05);各组在14日龄时血常规与血清生化指标差异不显著(P>0.05);在28,42日龄时,30,90,150 mg/kg组白细胞数、红细胞数、血红蛋白含量与对照组差异不显著(P>0.05),300 mg/kg组与对照组差异显著(P<0.05);300 mg/kg组肝脏重和肝脏指数显著高于对照组(P<0.05)。90,150,300 mg/kg组均有1只北京鸭死亡,对照组有2只死亡;150 mg/kg组有1只北京鸭肝脏颜色偏黄,300 mg/kg组有4只北京鸭肝脏肿大、颜色偏黄,发生轻度脂肪变性、肝细胞肿大、胞浆内发现近圆形空泡等病理变化。说明在饲料中添加30~90 mg/kg的博落回散可安全有效地促进北京鸭生长,当添加量为300 mg/kg时,北京鸭表现不耐受,生长性能下降,饲料转化率降低,并表现出肝脏损伤。 展开更多
关键词 北京鸭 博落回散 耐受性 生长性能 饲料转化率
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不同温比下自由活塞斯特林发电机的数值研究
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作者 张蓉 闫春杰 +2 位作者 罗新奎 屈方杰 孙述泽 《低温工程》 CAS CSCD 北大核心 2024年第5期79-86,共8页
为提高自由活塞斯特林动力系统的输出功率和热电转换效率,通过Sage软件对斯特林机的关键参数进行模拟研究,探讨关键参数在不同温比下对发电机输出功率和热电转换效率的影响。研究结果表明在不同温比下,相位角分别为80°和50°... 为提高自由活塞斯特林动力系统的输出功率和热电转换效率,通过Sage软件对斯特林机的关键参数进行模拟研究,探讨关键参数在不同温比下对发电机输出功率和热电转换效率的影响。研究结果表明在不同温比下,相位角分别为80°和50°时对应输出功率和热电转换效率最高,充气压力的增大对输出功率的增大效果显著,但对热电转换效率的影响较小;同温比下,提高冷端温度对输出功率和热电转换效率的影响大于提高热端温度的影响,但当温比为2.5时,冷端温度高于430 K后,热电转换效率反而降低。 展开更多
关键词 斯特林发电机 热电转换效率 相位角 充气压力 温比
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