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Progress on major genes for high fecundity in ewes

Qiuyue LIU,Zhangyuan PAN,Xiangyu WANG,Wenping HU,Ran DI,Yaxing YAO,Mingxing CHU

《农业科学与工程前沿(英文)》 2014年 第1卷 第4期   页码 282-290 doi: 10.15302/J-FASE-2014042

摘要: The existence of major genes affecting fecundity in sheep flocks throughout the world has been demonstrated. Three major genes whose mutations can increase ovulation rate have been discovered, and all related to the transforming growth factor β (TGF-β) superfamily. The mutant of bone morphogenetic protein receptor 1B (BMPR1B) has an additive effect on ovulation rate. Six mutations ( , , , , , ) of bone morphogenetic protein 15 (BMP15) related with fertility have been identified that share the same mechanism. All the mutants can increase ovulation rate in heterozygotes and cause complete sterility in homozygotes. Homozygous ewes with two new mutations ( ) of BMP15 had increased ovulation rate without causing sterility. There are five mutations in growth differentiation factor 9 (GDF9) associated with sheep prolificacy where and have additive an effect on ovulation rate and litter size. The newly identified β-1,4-N-acetylgalactosaminyltransferase 2 ( ) gene of is proposed as a new mechanism of ovulation rate regulation in sheep. is an X-linked maternally imprinted gene which increases ovulation rate. In addition, several putative major genes need to be verified. This review is focused on the identification of the mutations and mechanisms whereby the major genes affecting ovulation rate.

关键词: major gene     ovulation rate     sheep     reproduction    

两种特殊类型排卵障碍的超声监测和促排卵治疗疗效观察

刘莉,吴春林,胡雅君

《中国工程科学》 2015年 第17卷 第6期   页码 31-35

摘要:

目的:了解正常排卵、小卵泡排卵以及未破裂卵泡黄素化患者的临床特征及观察后两者经阴道B超再次监排情况和促排卵治疗效果。方法:回顾性分析了正常排卵组(258例)、小卵泡排卵组(65例)及未破裂卵泡黄素化组(27例)患者年龄、排卵前卵泡大小和基础性激素水平差异,观察了后两组排卵障碍患者经阴道B超再次监排情况。并对两次监排结果一致的58例小卵泡排卵和25例未破裂卵泡黄素化患者进行克罗米芬促排卵治疗,分别观察了这两种排卵障碍患者的正常排卵率及临床妊娠率。结果:正常排卵组、小卵泡排卵组和未破裂卵泡黄素化组患者平均年龄、基础性激素水平均无显著性差异。三组间排卵前卵泡最大平均径线有显著性差异(F=117.9,P<0.01)。小卵泡排卵和未破裂卵泡黄素化的发生率分别为18.57 %和7.71 %。两者再次监排后,再发率分别为89.23 %和92.59 %。经克罗米芬促排卵联合黄体支持治疗后,小卵泡排卵组和未破裂卵泡黄素化组正常排卵率分别为70.69 %和80 %,临床妊娠率分别为29.31 %和48 %。结论:年龄、基础性激素水平不能预测是否正常排卵,经阴道B超监测是诊断小卵泡排卵以及未破裂卵泡黄素化的直观方法。不经过治疗两者再发率高,促排卵治疗联合黄体支持是治疗小卵泡排卵以及未破裂卵泡黄素化的有效方法。

关键词: 经阴道超声;排卵监测;小卵泡排卵;未破裂卵泡黄素化;促排卵治疗    

The combined effects of biomass and temperature on maximum specific ammonia oxidation rate in domestic

《环境科学与工程前沿(英文)》 2021年 第15卷 第6期 doi: 10.1007/s11783-021-1411-9

摘要:

• Actual SAORs was determined using MLVSS and temperature.

关键词: Specific ammonia oxidation rate     Sequencing batch reactor     Biomass     Temperature coefficient     Model simulation    

Use of float consumption rate in resource leveling of construction projects

Atilla DAMCI, Gul POLAT, Firat Dogu AKIN, Harun TURKOGLU

《工程管理前沿(英文)》 2022年 第9卷 第1期   页码 135-147 doi: 10.1007/s42524-020-0118-0

摘要: The management of resources has been claimed to be as important as scheduling methods. Inefficiency in managing resources may bring about severe delays and cost overruns caused by resource shortages in some cases and/or idle resources in others. Therefore, resources should be utilized efficiently to prevent project failures. Resource leveling is one of the approaches that are used for the management of resources. It aims to minimize fluctuations, peaks, and valleys in resource utilization without changing the completion time of a project and the number of resources required. Although the main principle behind traditional resource leveling is achieving an even flow of resources while the original project duration remains unchanged, the literature supports the need to develop an efficient model that discriminates among the activities that are selected for participation in resource leveling. For this purpose, this study has developed a model that considers the float consumption rates of activities in resource leveling. The float consumption rate is the percentage that is set to determine the maximum amount of float which will be consumed to shift the start time of the activity. The proposed model allows a scheduler to assign float consumption rates to each activity that can be used during the resource leveling procedure. When the required information is inputted, the proposed model automatically changes the required daily resources as it shifts the noncritical activities along their available total float times. The proposed model is expected to minimize the likelihood of severe delays and cost overruns. The model is demonstrated by constructing a network and its resource utilization histograms.

关键词: resource management     resource leveling     float consumption rate     scheduling    

Effect of loading rate on shear strength parameters of mechanically and biologically treated waste

《环境科学与工程前沿(英文)》 2022年 第16卷 第12期 doi: 10.1007/s11783-022-1595-7

摘要:

● Mechanical behavior of MBT waste affected by loading rate was investigated.

关键词: Mechanically and biologically treated waste     Landfill     Triaxial test     Loading rate     Axial strain     Shear strength parameter    

Size-controllable synthesis of monodispersed nitrogen-doped carbon nanospheres from polydopamine for high-rate

《化学科学与工程前沿(英文)》 2023年 第17卷 第11期   页码 1788-1800 doi: 10.1007/s11705-023-2326-8

摘要: Monodispersed nitrogen-doped carbon nanospheres with tunable particle size (100–230 nm) were synthesized via self-polymerization of biochemical dopamine in the presence of hexamethylenetetramine as a buffer and F127 as a size controlling agent. Hexamethylenetetramine can mildly release NH3, which in turn initiates the polymerization reaction of dopamine. The carbon nanospheres obtained exhibited a significant energy storage capability of 265 F·g–1 at 0.5 A·g–1 and high-rate performance of 82% in 6 mol·L–1 KOH (20 A·g–1), which could be attributed to the presence of abundant micro-mesoporous structure, doped nitrogen functional groups and the small particle size. Moreover, the fabricated symmetric supercapacitor device displayed a high stability of 94% after 5000 cycles, revealing the considerable potential of carbon nanospheres as electrode materials for energy storage.

关键词: carbon nanospheres     size-controlled     nitrogen-doped     high-rate     supercapacitors    

Improved rate-based modeling of carbon dioxide absorption with aqueous monoethanolamine solution

Stefania MOIOLI, Laura A. PELLEGRINI, Simone GAMBA, Ben LI

《化学科学与工程前沿(英文)》 2014年 第8卷 第1期   页码 123-131 doi: 10.1007/s11705-014-1415-0

摘要: This paper focuses on modeling and simulation of a post-combustion carbon dioxide capture in a coal-fired power plant by chemical absorption using monoethanolamine. The aim is to obtain a reliable tool for process simulation: a customized rate-based model has been developed and implemented in the ASPEN Plus software, along with regressed parameters for the Electrolyte-NRTL model worked out in a previous research. The model is validated by comparison with experimental data of a pilot plant and can provide simulation results very close to experimental data.

关键词: Absorption     carbon dioxide capture     rate-based model     monoethanolamine scrubbing    

Modified landfill gas generation rate model of first-order kinetics and two-stage reaction

Jiajun CHEN , Hao WANG , Na ZHANG ,

《环境科学与工程前沿(英文)》 2009年 第3卷 第3期   页码 313-319 doi: 10.1007/s11783-009-0025-4

摘要: This investigation was carried out to establish a new domestic landfill gas (LFG) generation rate model that takes into account the impact of leachate recirculation. The first-order kinetics and two-stage reaction (FKTSR) model of the LFG generation rate includes mechanisms of the nutrient balance for biochemical reaction in two main stages. In this study, the FKTSR model was modified by the introduction of the outflow function and the organic acid conversion coefficient in order to represent the in-situ condition of nutrient loss through leachate. Laboratory experiments were carried out to simulate the impact of leachate recirculation and verify the modified FKTSR model. The model calibration was then calculated by using the experimental data. The results suggested that the new model was in line with the experimental data. The main parameters of the modified FKTSR model, including the LFG production potential (), the reaction rate constant in the first stage (), and the reaction rate constant in the second stage () of 64.746 L, 0.202 d, and 0.338 d, respectively, were comparable to the old ones of 42.069 L, 0.231 d, and 0.231 d. The new model is better able to explain the mechanisms involved in LFG generation.

关键词: landfill gas (LFG)     generation rate model     first-order kinetics     two-stage reaction     outflow function    

arrays as promising current collectors for constructing solid-state supercapacitors with ultrahigh rate

Huaping Zhao, Long Liu, Yaoguo Fang, Ranjith Vellacheri, Yong Lei

《化学科学与工程前沿(英文)》 2018年 第12卷 第3期   页码 339-345 doi: 10.1007/s11705-018-1699-6

摘要:

In this work, nickel nanopore arrays with a highly-oriented nanoporous structure inherited from porous alumina membranes were used as nanostructured current collectors for constructing ultrahigh rate solid-state supercapacitors. A thin layer of poly(3,4-ethylenedioxythiophene) (PEDOT) as electroactive materials was conformally coated onto nickel nanopores to form heterostructured electrodes. The as-prepared electrodes have a large specific surface area to ensure a high capacity, and the highly-oriented nanoporous structure of nickel nanopores reduces the ion transport resistance, allowing the ions in the solid-state electrolytes to quickly access the PEDOT surface during the fast charge-discharge process. As a result, the assembled solid-state supercapacitor in a symmetric configuration exhibits an ideal capacitive behavior and a superior rate capability even at an ultrahigh scan rate of 50 V·s1.

关键词: supercapacitor     ultrahigh rate     metallic nanopore arrays     current collectors     PEDOT    

Economic Growth Model Based on Six Basic Factors of Production—Xu Growth Rate Equation

Shou-bo Xu,Zong-yuan Huang

《工程管理前沿(英文)》 2014年 第1卷 第2期   页码 160-175 doi: 10.15302/J-FEM-2014024

摘要: This paper proposes an economic growth model based on the Six Basic Factors of Production and Xu Growth Rate Equation for the first time, which fills-in the deficits of the New Classical Economic Growth Model based on the Solow Model. The empirical analysis indicates that over the past three decades, the consumption of six basic factors of production had complicated relations with economic growth. In some years, the consumption rate of the basic factors of production was meager, but the economy witnessed relatively rocketing growth rate; in some years, the factors of production consumption rate was very high, but the economy growth rate slowed down. In general, economy grows at the expenses of huge consumption of four factors. There is an obvious characteristic of huge input and low efficiency. The average contribution rate of technological advance peaks in the middle, while it drops down at two ends. Noticeably, since 2004, the technology contribution rate generally shows a downward trend, reasons of which should be explored systematically in aspects like economic policy and industry structure with a view to boost further transformation of the macro-economy scientific growth model.

关键词: six basic factors of production     economic growth model     Xu Growth Rate Equation    

Petroleum pitch derived hard carbon via NaCl-template as anode materials with high rate performance for

《化学科学与工程前沿(英文)》 doi: 10.1007/s11705-024-2430-4

摘要: Sodium-ion batteries (SIBs) have garnered significant interest in energy storage due to their similar working mechanism to lithium ion batteries and abundant reserves of sodium resource. Exploring facile synthesis of a carbon-based anode materials with capable electrochemical performance is key to promoting the practical application of SIBs. In this work, a combination of petroleum pitch and recyclable sodium chloride is selected as the carbon source and template to obtain hard carbon (HC) anode for SIBs. Carbonization times and temperatures are optimized by assessing the sodium ion storage behavior of different HC materials. The optimized HC exhibits a remarkable capacity of over 430 mAh·g–1 after undergoing full activation through 500 cycles at a density of current of 0.1 A·g–1. Furthermore, it demonstrates an initial discharge capacity of 276 mAh·g–1 at a density of current of 0.5 A·g–1. Meanwhile, the optimized HC shows a good capacity retention (170 mAh·g–1 after 750 cycles) and a remarkable rate ability (166 mAh·g–1 at 2 A·g–1). The enhanced capacity is attributed to the suitable degree of graphitization and surface area, which improve the sodium ion transport and storage.

关键词: petroleum pitch     hard carbon     sodium-ion batteries     high rate     recyclable template    

Effect of dilution rate on dynamic and steady-state biofilm characteristics during phenol biodegradation

Veena Bangalore Rangappa, Vidya Shetty Kodialbail, Saidutta Malur Bharthaiyengar

《环境科学与工程前沿(英文)》 2016年 第10卷 第4期 doi: 10.1007/s11783-016-0863-9

摘要: Continuous pulsed plate bioreactor (PPBR) was used for phenol biodegradation. cells immobilized on granular activated carbon was used. Dynamic and steady state biofilm characteristics depend on dilution rate (DR). Lower DR favour phenol degradation and uniform, thick biofilm formation. Exo polymeric substance production in biofilm are favoured at lower dilution rates. Pulsed plate bioreactor (PPBR) is a biofilm reactor which has been proven to be very efficient in phenol biodegradation. The present paper reports the studies on the effect of dilution rate on the physical, chemical and morphological characteristics of biofilms formed by the cells of Pseudomonas desmolyticum on granular activated carbon (GAC) in PPBR during biodegradation of phenol. The percentage degradation of phenol decreased from 99% to 73% with an increase in dilution rate from 0.33 h?1 to 0.99 h?1 showing that residence time in the reactor governs the phenol removal efficiency rather than the external mass transfer limitations. Lower dilution rates favor higher production of biomass, extracellular polymeric substances (EPS) as well as the protein, carbohydrate and humic substances content of EPS. Increase in dilution rate leads to decrease in biofilm thickness, biofilm dry density, and attached dry biomass, transforming the biofilm from dense, smooth compact structure to a rough and patchy structure. Thus, the performance of PPBR in terms of dynamic and steady-state biofilm characteristics associated with phenol biodegradation is a strong function of dilution rate. Operation of PPBR at lower dilution rates is recommended for continuous biologic treatment of wastewaters for phenol removal.

关键词: Biofilm     Exopolymeric substances     Phenol     Dilution rate     Pulsed plate bioreactor    

Setting up a heart rate alarm limit to decrease oculocardiac reflex during strabismus surgery in children

ZHANG Kangkang, GU Enhua, LU Junjie

《医学前沿(英文)》 2008年 第2卷 第3期   页码 295-297 doi: 10.1007/s11684-008-0056-4

摘要: The aim of this paper is to investigate a method which may decrease the incidence and severity of oculocardiac reflex (OCR) without drugs. One hundred and sixty children undergoing strabismus surgery were allocated to two groups using double-blind randomization. OCR was defined as a decrease of more than 10% from the baseline heart rate during operation. An alarm sounded and a lamp flashed as soon as OCR occurred in group I, and neither of the above happened in group II. OCR occurred (1.151 ± 0.858) times in group I and (2.287 ± 1.371) times in group II ( < 0.05). Heart rate decreased by (23 ± 19) bpm in group I and (35 ± 28) bpm in group II ( < 0.05). The duration of OCR in group I and group II was (4.36 ± 4.26)s and (7.62 ± 6.41)s, respectively ( < 0.05). The recovery time for group I and group II was (15.36 ± 13.28)s and (32.36 ± 19.57)s, respectively ( < 0.05). The numbers of times of interruption were 8 in group I (10%) and 26 in group II (32%) ( < 0.01). This method significantly decreased the incidence and severity of OCR during strabismus surgery in children.

Influence of different oil feed rate on bituminous coal ignition in a full-scale tiny-oil ignition burner

Chunlong LIU, Qunyi ZHU, Zhengqi LI, Qiudong ZONG, Xiang ZHANG, Zhichao CHEN

《能源前沿(英文)》 2013年 第7卷 第3期   页码 406-412 doi: 10.1007/s11708-013-0266-6

摘要: To reduce oil consumption during firing-up and partial-load operation, a tiny-oil ignition burner has been recommended. Through reacting-flow experiments performed on a full-scale experimental setup, the influence of different oil flow rates on bituminous coal combustion as well as flow rates without coal feed was analyzed. The ignition burner is identical to that normally used in an 800 MWe utility boiler. Under operating conditions with flow rates of 50, 100, and 150 kg/h, gas temperature distributions were measured in the burner. At the equivalent measuring points at the exits of the first and second combustion chambers, these distributions remained almost unchanged under a constant coal feed rate of 4 t/h. However on the burner centerline, distributions increased slightly with increasing flow rate. Different gas concentrations were measured at the center of the burner exit. For instance, the O concentration at the burner exit varied from 0.01% to 0.31% whereas CO concentrations were more than 10000 ppm. At the same coal feed rate of 4 t/h, burner resistances are 480, 600, and 740 Pa for oil flow rates of 50, 100, and 150 kg/h, respectively.

关键词: ignition     coal     burner     boiler     oil flow rate    

Realtime prediction of hard rock TBM advance rate using temporal convolutional network (TCN) with tunnel

Zaobao LIU; Yongchen WANG; Long LI; Xingli FANG; Junze WANG

《结构与土木工程前沿(英文)》 2022年 第16卷 第4期   页码 401-413 doi: 10.1007/s11709-022-0823-3

摘要: Real-time dynamic adjustment of the tunnel bore machine (TBM) advance rate according to the rock-machine interaction parameters is of great significance to the adaptability of TBM and its efficiency in construction. This paper proposes a real-time predictive model of TBM advance rate using the temporal convolutional network (TCN), based on TBM construction big data. The prediction model was built using an experimental database, containing 235 data sets, established from the construction data from the Jilin Water-Diversion Tunnel Project in China. The TBM operating parameters, including total thrust, cutterhead rotation, cutterhead torque and penetration rate, are selected as the input parameters of the model. The TCN model is found outperforming the recurrent neural network (RNN) and long short-term memory (LSTM) model in predicting the TBM advance rate with much smaller values of mean absolute percentage error than the latter two. The penetration rate and cutterhead torque of the current moment have significant influence on the TBM advance rate of the next moment. On the contrary, the influence of the cutterhead rotation and total thrust is moderate. The work provides a new concept of real-time prediction of the TBM performance for highly efficient tunnel construction.

关键词: hard rock tunnel     tunnel bore machine advance rate prediction     temporal convolutional networks     soft computing     construction big data    

标题 作者 时间 类型 操作

Progress on major genes for high fecundity in ewes

Qiuyue LIU,Zhangyuan PAN,Xiangyu WANG,Wenping HU,Ran DI,Yaxing YAO,Mingxing CHU

期刊论文

两种特殊类型排卵障碍的超声监测和促排卵治疗疗效观察

刘莉,吴春林,胡雅君

期刊论文

The combined effects of biomass and temperature on maximum specific ammonia oxidation rate in domestic

期刊论文

Use of float consumption rate in resource leveling of construction projects

Atilla DAMCI, Gul POLAT, Firat Dogu AKIN, Harun TURKOGLU

期刊论文

Effect of loading rate on shear strength parameters of mechanically and biologically treated waste

期刊论文

Size-controllable synthesis of monodispersed nitrogen-doped carbon nanospheres from polydopamine for high-rate

期刊论文

Improved rate-based modeling of carbon dioxide absorption with aqueous monoethanolamine solution

Stefania MOIOLI, Laura A. PELLEGRINI, Simone GAMBA, Ben LI

期刊论文

Modified landfill gas generation rate model of first-order kinetics and two-stage reaction

Jiajun CHEN , Hao WANG , Na ZHANG ,

期刊论文

arrays as promising current collectors for constructing solid-state supercapacitors with ultrahigh rate

Huaping Zhao, Long Liu, Yaoguo Fang, Ranjith Vellacheri, Yong Lei

期刊论文

Economic Growth Model Based on Six Basic Factors of Production—Xu Growth Rate Equation

Shou-bo Xu,Zong-yuan Huang

期刊论文

Petroleum pitch derived hard carbon via NaCl-template as anode materials with high rate performance for

期刊论文

Effect of dilution rate on dynamic and steady-state biofilm characteristics during phenol biodegradation

Veena Bangalore Rangappa, Vidya Shetty Kodialbail, Saidutta Malur Bharthaiyengar

期刊论文

Setting up a heart rate alarm limit to decrease oculocardiac reflex during strabismus surgery in children

ZHANG Kangkang, GU Enhua, LU Junjie

期刊论文

Influence of different oil feed rate on bituminous coal ignition in a full-scale tiny-oil ignition burner

Chunlong LIU, Qunyi ZHU, Zhengqi LI, Qiudong ZONG, Xiang ZHANG, Zhichao CHEN

期刊论文

Realtime prediction of hard rock TBM advance rate using temporal convolutional network (TCN) with tunnel

Zaobao LIU; Yongchen WANG; Long LI; Xingli FANG; Junze WANG

期刊论文