• International Journal of Fluid Machinery and Systems
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• v.8 no.2
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• pp.94-101
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• 2015

To investigate the influence of blade profiles on cavitation behavior in impeller of centrifugal pump, a centrifugal pump with five different blade profiles impellers are studied numerically. The impellers with five different blade profiles (single arc, double arcs, triple arcs, logarithmic spiral and linear-variable angle spiral) were designed by the in-house hydraulic design code using geometric parameters of IS 150-125-125 centrifugal pump. The experiments of the centrifugal pump have been conducted to verify numerical simulation model. The numerical results show that the blade profile lines has a weak effect on cavitation inception near blade inlet edge position, however it has the key effect on the development of sheet cavitation in impeller, and also influences the distribution of sheet cavitation in impeller channels. A slight changing of blade setting angle will induce significant difference of cavitation in impeller. The sharp changing of impeller blade setting angle causes obvious cavitation region separation near the impeller inlet close to blade suction surface and much more flow loss. The centrifugal pump with blade profile of setting angle gently changing (logarithmic spiral) has the super cavitation performance, which means smaller critical cavitation number and lower vapor cavity volume fraction at the same conditions.

• Journal of Fisheries and Marine Sciences Education
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• v.26 no.4
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• pp.749-759
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• 2014

With the rapid development of global economic and trade, the ports in the North-east Asia region have developed rapidly. Ocean shipping plays an irreplaceable role in China's foreign trade. Improvement of China's economy and continuous increase of trade in North-East Asia have made China as the number one in the world in container transport. Tianjin port which is the biggest international trade port in North-east China. Tianjin Binhai New District has incorporated in (CPC Central Committee on the outline of the Eleventh Five-Year Plan for national economic and social development proposals) which had adopted by The Fifth Plenary Session of the 16th CPC Central Committee. However, the competitions between ports are getting intense, the construction of Northeast Asia shipping center is in the ascendant, which bring new opportunity and challenge to the development of Tianjin port logistics. Therefore, Tianjin should according to its characteristics, integrating port resources, exert great efforts in developing port logistics, thus promoting regional economic development. Therefore, it is necessary to make the main study on the development strategy of Tianjin port logistics.

• Parasites, Hosts and Diseases
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• v.53 no.6
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• pp.683-688
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• 2015

Human diphyllobothriasis is a widespread fish-borne zoonosis caused by the infection with broad tapeworms belonging to the genus Diphyllobothrium. In mainland China, so far 20 human cases of Diphyllobothrium infections have been reported, and the etiologic species were identified as D. latum and D. nihonkaiense based on morphological characteristics or molecular analysis. In the present study, proglottids of diphyllobothriid tapeworms from 3 human cases that occurred in Heilongjiang Province, China were identified as D. nihonkaiense by sequencing mitochondrial cytochrome c oxidase subunit I (cox1) and NADH dehydrogenase subunit 5 (nad5) genes. Two different cox1 gene sequences were obtained. One sequence showed 100% homology with those from humans in Japan. The remaining cox1 gene sequence and 2 different nad5 gene sequences obtained were not described previously, and might reflect endemic genetic characterizations. D. nihonkaiense might also be a major causative species of human diphyllobothriasis in China. Meanwhile, the finding of the first pediatric case of D. nihonkaiense infection in China suggests that infants infected with D. nihonkaiense should not be ignored.

• Asian Pacific Journal of Cancer Prevention
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• v.13 no.10
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• pp.5003-5006
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• 2012

Objective: Yanting County is a high risk area for esophageal cancer (EC) in China. The purpose of this study was to describe the mortality and mortality change of EC from 2004 to 2009 in Yanting County. Methods: EC mortality data from 2004 to 2009 obtained from the Cancer Registry in Yanting were analyzed. Annual percentage changes (APC) were calculated to assess the trends in EC mortality. Age-standardized mortality was calculated based on world standard population of 2000. Results: The average EC mortality was 54.7/$10^5$ in males and 31.6/$10^5$ in females over the 6 years. A decline in EC mortality with time was observed in both genders, with a rate of -8.70% per year (95% CI: -13.23%~-3.93%) in females and -4.11% per year (95%CI: -11.16%~3.50%) in males. Conclusion: EC mortality decreased over the six years in both genders, although it remained high in the Yanting area. There is still a need to carry out studies of risk factors for improved cancer prevention and further reduction in the disease burden.

• Bulletin of the Korean Chemical Society
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• v.32 no.1
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• pp.127-130
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• 2011

One new tirucallane-type triterpenoid, alianthusaltinin A (1), one new $C_{29}$ sterone, alianthaltone A (2), and 12 known compounds have been isolated from the stem bark of Ailanthus altissima. The structures of new compounds were identified by means of spectroscopic methods. Compound 3 was isolated from natural sources for the first time, and compounds 4, 5, and 9 were isolated from this plant for the first time.

• Journal of Arbitration Studies
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• v.25 no.2
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• pp.97-118
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• 2015

As China has quickly emerged as a global economic power, the total number of international commercial disputes arbitrated by Chinese arbitral institutions has increased dramatically. Along with this, the annulment procedure of arbitral awards in China have been newly brought to the fore. In accordance with the historical background and the demand of the times, the Chinese annulment procedure of arbitral awards reveals distinctive Chinese features. Although it was enacted in the face ofof an unwarranted prejudice against the dispute settlement system by arbitration as well as a deep mistrust of domestic arbitral institutions, the annulment procedure of arbitral awards showed a certain degree of justification and rationality in its initial stages of legislation. However, it is also the case that it has not adapted well to new domestic or foreign arbitration circumstances in the last twenty years. At present, there is a keen interest in revisions to and debates on arbitration law of China. It is necessary to take an active part in the amendment discussion and process of arbitration law. Moreover, we need to reform the annulment procedure of arbitral awards in order to meet the global trend of arbitration law.

• Korean Journal of Chemical Engineering
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• v.35 no.12
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• pp.2355-2364
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• 2018

We evaluated the effect of particle size and associated dynamics on a hydrocyclone separation process in order to understand the movement of the particle trajectories inside the hydrocyclone via numerical analysis, with particles of acid hydrolysis residues discharged in $TiO_2$ production via the sulfate method as a case study. The values obtained from the numerical simulation were successfully compared with those from experimental tests in the literature, allowing a description of the dynamics of the particles, their acting forces, and their relevant properties together with separation efficiency. The results showed that particle motion is jointly controlled by the drag force, the pressure gradient force and the centrifugal force. With increasing particle size, the influence of the drag force is weakened, whereas that of the centrifugal force and pressure gradient is strengthened. Factors including particle density, slurry viscosity, and inlet slurry flow rate also contribute to a clear and useful understanding of particle motion behavior in the hydrocyclone as a method for improving the separation efficiency.

• Nuclear Engineering and Technology
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• v.53 no.12
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• pp.4033-4041
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• 2021

To better understand the permeability of uranium sandstone, improve the leaching rate of uranium, and explore the change law of pore structure characteristics and blocking mechanism during leaching, we systematically analyzed the microstructure of acid-leaching uranium sandstone. We investigated the variable rules of pore structure characteristics based on nuclear magnetic resonance (NMR). The results showed the following: (1) The uranium concentration change followed the exponential law during uranium deposits acid leaching. After 24 h, the uranium leaching rate reached 50%. The uranium leaching slowed gradually over the next 4 days. (2) Combined with the regularity of porosity variation, Stages I and II included chemical plugging controlled by surface reaction. Stage I was the major completion phase of uranium displacement with saturation precipitation of calcium sulfate. Stage II mainly precipitated iron (III) oxide-hydroxide and aluminum hydroxide. Stage III involved physical clogging controlled by diffusion. (3) In the three stages of leaching, the permeability of the leaching solution changed with the pore structure, which first decreased, then increased, and then decreased.

• The Korea Journal of Herbology
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• v.24 no.4
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• pp.1-8
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• 2009

Objectives : This study was carried out to discriminate origin and molecular marker of oriental medicine "Cnidii Rhizoma" be circulated between Korea and China, which is difficult to discriminate from morphological distinction because of a fragmental materials of roots. Methods : Materials were collected randomly from a medicinal herb markets in Korea and China and be analyzed with ITS (internal transcribed spacer) regions of nuclear ribosomal DNA (nrDNA). Results : As a results, ITS regions of nrDNA was shown to be identify as three molecular markers. "Cnidii Rhizoma" was made up syster group of the genus Ligusticum L. and divided into three groups with "Tou-chun-gung", "IL-chun-gung" and "China-chun-gung". Conclusions : From the analysis of ITS regions of nrDNA, we presumed that it is the same origin of "Cnidii Rhizoma" from Korea and China because of phylogenetic tree consisted of sister groups with the genus Ligusticum than the genus Cnidium.

• Journal of the Korean Institute of Landscape Architecture International Edition
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• no.1
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• pp.202-207
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• 2001

Covering an area of about 39 ha, Qingming Shanghe Park is located in the northwest of Kaifeng, formerly the capital of seven dynasties in China. It is intended to serve as a tourist attraction based on a painting 〃Qingming Festival at Riverside〃 by Zhang Zeduan of the Northern song Dynasty, which vividly illustrates a real life on the both sides of the Bian River as well as in the urban area, Kaifeng, in early Spring. The park is a collection of varied buildings such as shops, restaurants, tea-houses, theaters, and hotels in the North song style, with an introduction of the history of Kaifeng, this paper examines design philosophy and methodology of the park, and discusses the creative design of the first stage development known as known as The South Area of the park. Marked by the Rainbow Bridge and the City Gate, the South Area is divided into three parts, the rural, suburban, and urban parts which are organized according to the spatial order showed in the painting. The South Area proves to be very successful because of its amazing sense of history and interesting folk performance. Furthermore, the preliminary 9planning of the second stage development known as The North Area is presented with references to culture, history and customs. The North Area is proposed to include the Old Sports & Games Garden, the Exhibition Garden, and the Hot Spring Garden with an appearance of the imperial gardens in the Northern Song, integrated with participation of old sports and games, display of old science & technology achievements, and enjoyment of hot spring bath.