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Optimization of urban bus operation frequency under common route condition with rail transit

Bin YU, Sijia REN, Enze WU, Yifan ZHOU, Yunpeng WANG

《工程管理前沿(英文)》 2017年 第4卷 第4期   页码 451-462 doi: 10.15302/J-FEM-2017036

摘要: The overlap of bus and rail transit routes is common in China. This overlap provides passengers multiple choices for one trip. However, the availability of multiple options would cause uncertainty in the travel distribution of passengers. Given that buses and rail transits are becoming increasingly common, this paper aims to present the overlapped operation condition of bus and rail transit using a bi-level model from the perspective of bus operators. Frequency optimization model is established in the upper-level model. A heuristic algorithm called shuffled complex evolution (SCE-UA) method is used to solve the established frequency optimization model, and three other heuristic methods are compared with SCE-UA. A lower-level Logit model based on Agent simulation is set for traffic mode split. Data on the transit system in Dalian city are chosen as an example to test the feasibility of the model and the algorithm. Results show that as the overlapped optimization of bus route and rail transit routes changed primary bus frequency, the use of SCE-UA to solve such problems has evident advantages and feasibility; furthermore, changed bus frequency would improve bus operations.

关键词: common route     bus operation frequency     bi-level model     Agent simulation     SCE-UA algorithm    

Advances in some common chronic liver diseases

null

《医学前沿(英文)》 2014年 第8卷 第2期   页码 127-128 doi: 10.1007/s11684-014-0341-3

Facile route to achieve MoSe-NiSe on nickel foam as efficient dual functional electrocatalysts for overall

《能源前沿(英文)》 2022年 第16卷 第3期   页码 483-491 doi: 10.1007/s11708-022-0813-0

摘要: Since the catalytic activity of present nickel-based synthetic selenide is still to be improved, MoSe2-Ni3Se2 was synthesized on nickel foam (NF) (MoSe2-Ni3Se2/NF) by introducing a molybdenum source. After the molybdenum source was introduced, the surface of the catalyst changed from a single-phase structure to a multi-phase structure. The catalyst surface with enriched active sites and the synergistic effect of MoSe2 and Ni3Se2 together enhance the hydrogen evolution reactions (HER), the oxygen evolution reactions (OER), and electrocatalytic total water splitting activity of the catalyst. The overpotential of the MoSe2-Ni3Se2/NF electrocatalyst is only 259 mV and 395 mV at a current density of 100 mA/cm2 for HER and OER, respectively. MoSe2-Ni3Se2/NF with a two-electrode system attains a current density of 10 mA/cm2 at 1.60 V. In addition, the overpotential of HER and OER of MoSe2-Ni3Se2/NF within 80000 s and the decomposition voltage of electrocatalytic total water decomposition hardly changed, showing an extremely strong stability. The improvement of MoSe2-Ni3Se2/NF catalytic activity is attributed to the establishment of the multi-phase structure and the optimized inoculation of the multi-component and multi-interface.

关键词: three-dimensional molybdenum nanomaterials     hydrogen evolution reaction     oxygen evolution reaction     overall water splitting    

Top-geoherbs of traditional Chinese medicine: common trait, quality characteristics and formation

Luqi Huang, Lanping Guo, Chaoyi Ma, Wei Gao, Qingjun Yuan

《医学前沿(英文)》 2011年 第5卷 第2期   页码 185-194 doi: 10.1007/s11684-011-0141-y

摘要: Top-geoherbs used in China are always featured with high qualities, and they grow in specified areas with specific environment. Recently, researches on top-geoherbs have attracted increasing attention in China and other countries. In order to have a thorough knowledge of top-geoherbs, this article reviews the concept, historical evolution, common trait and quality characteristics of top-geoherbs, and explains the forming mechanism including genetic mechanism and environmental mechanism. In addition, it introduces the influence of human factors on the quality of top-geoherbs. Finally, it proposes some problems that should be paid attention to in the researches on top-geoherbs.

关键词: top-geoherbs     common trait     quality characteristics     formation     biological mechanism    

ROUTE DEVELOPMENT, ANTIVIRAL STUDIES, FIELD EVALUATION AND TOXICITY OF AN ANTIVIRAL PLANT PROTECTANT

《农业科学与工程前沿(英文)》 2022年 第9卷 第1期 doi: 10.15302/J-FASE- 2021390

摘要:

It has previously been shown that tryptophan, the biosynthesis precursor of Peganum harmala alkaloids, and its derivatives have anti-TMV activity both in vitro and in vivo. Further exploration of this led to the identification of NK0238 as a highly effective agent for the prevention and control of diseases caused by plant viruses, but the existing routes are unsuitable for its large-scale synthesis. This study optimized a route for two-step synthesis of this virucide candidate via reaction of l-tryptophan with triphosgene to produce l-tryptophan-N-carboxylic anhydride, which then reacts with n-octylamine to give NK0238 at up to 94% yield and nearly 97% HPLC purity. In addition, the route was used for the preparation of NK0238 on a>40 g scale permitting further assessment of its antivirus activity in the greenhouse and field experiments, and toxicity tests. NK0238 exhibited useful antiviral activities against a variety of viruses both in greenhouse and field experiments. The toxicity tests showed that NK0238 was not acutely toxic to birds, fish, honey bees and silkworms. The optimized route provides a solid foundation for its large-scale synthesis and subsequent efficacy and toxicity studies, its excellent activity and safety make NK0238 a promising drug candidate for further development.

 

关键词: antiviral plant protectant / antiviral in the greenhouse / field evaluation / l-trp-NCA / synthesis optimization / toxicity tests    

Aerosol transmission, an indispensable route of COVID-19 spread: case study of a department-store cluster

《环境科学与工程前沿(英文)》 2021年 第15卷 第3期 doi: 10.1007/s11783-021-1386-6

摘要:

• Aerosol transmission is an indispensable route of COVID-19 spread.

关键词: SARS-CoV-2     COVID-19     Environmental factor     Aerosol transmission     Epidemiologic characteristic    

AGCD: a robust periodicity analysis method based on approximate greatest common divisor

Juan YU,Pei-zhong LU

《信息与电子工程前沿(英文)》 2015年 第16卷 第6期   页码 466-473 doi: 10.1631/FITEE.1400345

摘要: Periodicity is one of the most common phenomena in the physical world. The problem of periodicity analysis (or period detection) is a research topic in several areas, such as signal processing and data mining. However, period detection is a very challenging problem, due to the sparsity and noisiness of observational datasets of periodic events. This paper focuses on the problem of period detection from sparse and noisy observational datasets. To solve the problem, a novel method based on the approximate greatest common divisor (AGCD) is proposed. The proposed method is robust to sparseness and noise, and is efficient. Moreover, unlike most existing methods, it does not need prior knowledge of the rough range of the period. To evaluate the accuracy and efficiency of the proposed method, comprehensive experiments on synthetic data are conducted. Experimental results show that our method can yield highly accurate results with small datasets, is more robust to sparseness and noise, and is less sensitive to the magnitude of period than compared methods.

关键词: Periodicity analysis     Period detection     Sparsity     Noise     Approximate greatest common divisor (AGCD)    

Challenges of a feasible route towards sustainability in environmental protection

G. LETTINGA

《环境科学与工程前沿(英文)》 2010年 第4卷 第2期   页码 123-134 doi: 10.1007/s11783-010-0028-1

摘要: Anaerobic processes for treatment of low and high strength wastewaters and solid wastes constitute the core method in the natural biological mineralization (NBM) treatment concept. When adequately combined with the complementary NBM-systems and modern clean water saving practices in wastewater collection and transport, they represent a feasible route to sustainable environmental protection (EP), in essence even towards a more sustainable society. Despite the development and implementation of modern high rate Anaerobic Wastewater Treatment (AnWT-) systems and complementary innovative NBM-processes, the considerable progress made since the seventies in fundamental insights in microbiology, biochemistry and process technology, still numerous challenging improvements in the NBM-field can be realized. This contribution is mainly based on the insights attained from wide ranging literature evaluations and the results of experimental research conducted by numerous PhD students who participated in our group over the last four decades. An attempt is made here to identify major facets on which an improved insight can, and consequently should, be obtained in order to accomplish more optimal operation and design of various types of Anaerobic Degradation (AnDeg-) processes.

关键词: sustainability     environmental protection     anaerobic treatment     micro-aerobic treatment     natural biological mineralization concept     traces elements     macro-nutrients    

A chemical etching route to controllable fabrication of TiO

Weixin ZHANG, Jie XING, Zeheng YANG, Mei KONG, Hongxu YAO

《化学科学与工程前沿(英文)》 2013年 第7卷 第2期   页码 192-201 doi: 10.1007/s11705-013-1319-4

摘要: The TiO hollow nanospheres with diameters of about 230 nm were prepared by a simple and controllable route based on hydrolysis of Ti(OBu) on the surfaces of the Cu O solid nanospheres followed by inward etching of the Cu O nanospheres. The as-prepared samples were characterized by X-ray diffraction, transmission electron microscopy and scanning electron microscopy. The further post-heat treatment led to the high crystallization of the TiO hollow nanospheres. The photocatalytic performances of these samples were evaluated for the photodegradation of rhodamine B (RhB) under UV-light irradiation. The as-prepared TiO hollow nanospheres showed higher photocatalytic activity than the CuO and the CuO/TiO hollow nanospheres. Effects of temperature and time for post-heat treatment of TiO as well as initial RhB concentrations on the RhB photodegradation have also been studied. The results show that the TiO hollow nanospheres have the good reusability as photocatalysts and are promising in waste water treatment.

关键词: TiO2     hollow nanospheres     rhodamine B     photocatalytic activity    

Influence of cetane number improver on performance and emissions of a common-rail diesel engine fueled

Wu YU, Gen CHEN, Zuohua HUANG

《能源前沿(英文)》 2011年 第5卷 第4期   页码 412-418 doi: 10.1007/s11708-011-0163-9

摘要: In this paper, the effect of cetane number (CN) improver on performance and emissions, including particulate number concentration and size distribution, of a turbocharged, common-rail diesel engine fueled with biodiesel-methanol were studied. Two volume fractions (0.3% and 0.6%) of CN improver were added to BM30 (30% of methanol in the biodiesel-methanol blend) in the experiment. The results show that, compared with those of biodiesel-methanol blend, the peak value of cylinder pressure increases, the second peak of heat release rate decreases, the start of second heat release are advanced, and the fuel economy and thermal efficiency are improved when CN improver is added to biodiesel-methanol blend. Besides, CO and HC emissions decrease, NO emission varies little and smoke emissions increase slightly. Moreover, exhaust particles of BM30 mainly distribute in nano-size range. Furthermore, particle number concentration decreases and peak of size distribution profile shifts toward large size direction.

关键词: biodiesel     methanol     common-rail (CR) diesel engine     cetane number (CN) improver    

Effects of nano-silicon and common silicon on lead uptake and translocation in two rice cultivars

Jianguo LIU,Hui CAI,Congcong MEI,Mingxin WANG

《环境科学与工程前沿(英文)》 2015年 第9卷 第5期   页码 905-911 doi: 10.1007/s11783-015-0786-x

摘要: The current study investigated the effects of nano-silicon (Si) and common Si on lead (Pb) toxicity, uptake, translocation, and accumulation in the rice cultivars Yangdao 6 and Yu 44 grown in soil containing two different Pb levels (500 mg·kg and 1000 mg·kg ). The results showed that Si application alleviated the toxic effects of Pb on rice growth. Under soil Pb treatments of 500 and 1000 mg·kg , the biomasses of plants supplied with common Si and nano-Si were 1.8%–5.2% and 3.3%–11.8% higher, respectively, than those of plants with no Si supply (control). Compared to the control, Pb concentrations in rice shoots supplied with common Si and nano-Si were reduced by 14.3%–31.4% and 27.6%–54.0%, respectively. Pb concentrations in rice grains treated with common Si and nano-Si decreased by 21.3%–40.9% and 38.6%–64.8%, respectively. Pb translocation factors (TFs) from roots to shoots decreased by 15.0%–29.3% and 25.6%–50.8%, respectively. The TFs from shoots to grains reduced by 8.3%–13.7% and 15.3%–21.1%, respectively, after Si application. The magnitudes of the effects observed on plants decreased in the following order: nano-Si treatment>common Si treatment and high-grain-Pb-accumulating cultivar (Yangdao 6)>low-grain-Pb-accumulating cultivar (Yu 44) and heavy Pb stress (1000 mg·kg )>moderate Pb stress (500 mg·kg )>no Pb treatment. The results of the study indicate that nano-Si is more efficient than common Si in ameliorating the toxic effects of Pb on rice growth, preventing Pb transfer from rice roots to aboveground parts, and blocking Pb accumulation in rice grains, especially in high-Pb-accumulating rice cultivars and in heavily Pb-polluted soils.

关键词: silicon (Si)     lead (Pb)     rice (Oryza sativa L.)     toxicity     accumulation    

ROUTE DEVELOPMENT, ANTIVIRAL STUDIES, FIELD EVALUATION AND TOXICITY OF AN ANTIVIRAL PLANT PROTECTANT

Wentao XU, Hao TIAN, Hongjian SONG, Yuxiu LIU, Yongqiang LI, Qingmin WANG

《农业科学与工程前沿(英文)》   页码 110-119 doi: 10.15302/J-FASE-2021390

摘要: It has previously been shown that tryptophan, the biosynthesis precursor of alkaloids, and its derivatives have anti-TMV activity both and . Further exploration of this led to the identification of NK0238 as a highly effective agent for the prevention and control of diseases caused by plant viruses, but the existing routes are unsuitable for its large-scale synthesis. This study optimized a route for two-step synthesis of this virucide candidate via reaction of L-tryptophan with triphosgene to produce L-tryptophan- -carboxylic anhydride, which then reacts with -octylamine to give NK0238 at up to 94% yield and nearly 97% HPLC purity. In addition, the route was used for the preparation of NK0238 on a > 40 g scale permitting further assessment of its antivirus activity in the greenhouse and field experiments, and toxicity tests. NK0238 exhibited useful antiviral activities against a variety of viruses both in greenhouse and field experiments. The toxicity tests showed that NK0238 was not acutely toxic to birds, fish, honey bees and silkworms. The optimized route provides a solid foundation for its large-scale synthesis and subsequent efficacy and toxicity studies, its excellent activity and safety make NK0238 a promising drug candidate for further development.

关键词: antiviral plant protectant     antiviral in the greenhouse     field evaluation     L-trp-NCA     synthesis optimization     toxicity tests    

Dibutyl phthalate adsorption characteristics using three common substrates in aqueous solutions

Tiancui Li, Yaocheng Fan, Deshou Cun, Yanran Dai, Wei Liang

《环境科学与工程前沿(英文)》 2020年 第14卷 第2期 doi: 10.1007/s11783-019-1205-5

摘要: • DBP adsorption was tested using three kinds of substrates in constructed wetlands. • The DBP adsorption capacity followed the order: steel slag>gravel>shell sand. • High temperatures increased the DBP adsorption capacity in the substrates. • DOM consistently inhibited the DBP adsorption onto steel slag and gravel. In recent years, the presence and adverse impacts of phthalic acid esters in aquatic environments have gained increasing attention. This work investigated the adsorption behavior of a typical phthalic acid ester, dibutyl phthalate (DBP), onto steel slag, gravel, and shell sand (substrates commonly used in constructed wetlands). The influence of dissolved organic matter (DOM) on DBP adsorption was investigated using humic acid as a proxy for DOM. The results demonstrated that the adsorption of DBP to three substrates reached equilibrium within 96 h, and the adsorption kinetics were well fitted by a pseudo-second-order model. The DBP adsorption isotherms were best fitted by the Langmuir adsorption model. The DBP adsorption capacity decreased in the order of steel slag>gravel>shell sand, with values of 656 mg/kg, 598 mg/kg, and 6.62 mg/kg at 25°C, respectively. DBP adsorbed to the surface of all substrates in a monolayer via an endothermic process. The DBP adsorption capacities of steel slag and gravel decreased as the DOM content increased. The DBP adsorption mechanisms to steel slag and gravel mainly involved the surface coordination of DBP with –OH or –COOH groups and electrostatic interactions. The results of this work suggest that steel slag and gravel may be ideal substrates for use in constructed wetlands to treat wastewater polluted with DBP.

关键词: Adsorption     Dibutyl phthalate (DBP)     Dissolved organic matter     Substrates    

Agriculture Green Development in China and the UK: common objectives and converging policy pathways

Yuelai LU, David NORSE, David POWLSON

《农业科学与工程前沿(英文)》 2020年 第7卷 第1期   页码 98-105 doi: 10.15302/J-FASE-2019298

摘要:

This paper has three aims. First, to examine how the negative environmental consequences of intensive agriculture have driven China and the UK to shift away from narrowly focused farm output policies and adopt more holistic green development pathways. Second, to explore the policy objectives they have in common. Third, to assess the numerous opportunities for joint research and knowledge sharing through the Sustainable Agriculture Innovation Network and other existing institutional mechanisms. The intensification of agricultural production in the UK started several decades earlier than in China as did the negative environmental consequences of the farm practices. However, their strategies and policies for sustainable intensification and green development have much in common. These are set out in two main documents: the Chinese State Council guidelines for green agriculture and the UK Department for Environment, Food and Rural Affairs 25 Year Environment Plan. There are substantial mutual advantages from greater collaboration on problem identification and monitoring; the development of appropriate technological and management responses and the formulation of sound policies. To achieve this potential, it is recommended that further thought be given to how best to bring together all of the key stakeholders along the whole food chain.

关键词: Agriculture Green Development     China     policy     UK    

Research on pedestrian escape route without visibility based on Markov chain model

Xiaoping ZHENG, Lijuan DU, Hongjiang WANG,

《化学科学与工程前沿(英文)》 2010年 第4卷 第3期   页码 283-289 doi: 10.1007/s11705-009-0272-8

摘要: It is a pioneering work to use a Markov chain model to study the pedestrian escape route without visibility. In this paper, based on the Markov chain probability transition matrix, the algorithms with random numbers and the spatial-grid, an escape route in a limited invisible space is obtained. Six pace states (standing, crawling, walking, leaping, jogging, and running) are applied to describe the characteristics of pedestrian behaviors. Besides, eight main direction changes are used to describe the transition characteristic of a pedestrian. At the same time, this paper analyzes the escape route from two views, i.e., pedestrian pace states and directions. The research results show that the Markov chain model is more realistic as a means of studying pedestrian escape routes.

关键词: pioneering     direction     spatial-grid     realistic     transition characteristic    

标题 作者 时间 类型 操作

Optimization of urban bus operation frequency under common route condition with rail transit

Bin YU, Sijia REN, Enze WU, Yifan ZHOU, Yunpeng WANG

期刊论文

Advances in some common chronic liver diseases

null

期刊论文

Facile route to achieve MoSe-NiSe on nickel foam as efficient dual functional electrocatalysts for overall

期刊论文

Top-geoherbs of traditional Chinese medicine: common trait, quality characteristics and formation

Luqi Huang, Lanping Guo, Chaoyi Ma, Wei Gao, Qingjun Yuan

期刊论文

ROUTE DEVELOPMENT, ANTIVIRAL STUDIES, FIELD EVALUATION AND TOXICITY OF AN ANTIVIRAL PLANT PROTECTANT

期刊论文

Aerosol transmission, an indispensable route of COVID-19 spread: case study of a department-store cluster

期刊论文

AGCD: a robust periodicity analysis method based on approximate greatest common divisor

Juan YU,Pei-zhong LU

期刊论文

Challenges of a feasible route towards sustainability in environmental protection

G. LETTINGA

期刊论文

A chemical etching route to controllable fabrication of TiO

Weixin ZHANG, Jie XING, Zeheng YANG, Mei KONG, Hongxu YAO

期刊论文

Influence of cetane number improver on performance and emissions of a common-rail diesel engine fueled

Wu YU, Gen CHEN, Zuohua HUANG

期刊论文

Effects of nano-silicon and common silicon on lead uptake and translocation in two rice cultivars

Jianguo LIU,Hui CAI,Congcong MEI,Mingxin WANG

期刊论文

ROUTE DEVELOPMENT, ANTIVIRAL STUDIES, FIELD EVALUATION AND TOXICITY OF AN ANTIVIRAL PLANT PROTECTANT

Wentao XU, Hao TIAN, Hongjian SONG, Yuxiu LIU, Yongqiang LI, Qingmin WANG

期刊论文

Dibutyl phthalate adsorption characteristics using three common substrates in aqueous solutions

Tiancui Li, Yaocheng Fan, Deshou Cun, Yanran Dai, Wei Liang

期刊论文

Agriculture Green Development in China and the UK: common objectives and converging policy pathways

Yuelai LU, David NORSE, David POWLSON

期刊论文

Research on pedestrian escape route without visibility based on Markov chain model

Xiaoping ZHENG, Lijuan DU, Hongjiang WANG,

期刊论文