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Sanmenxia, China

He C.,Northwest University, China | Meng Q.,Sanmenxia Polytechnic | Hua L.,Northwest University, China | Chen W.,Northwest University, China
Shengtai Xuebao/ Acta Ecologica Sinica | Year: 2011

Oriental fruit moth (OFM), Grapholita molesta (Busck), is a key pest of tree fruit. Diapause plays an important role in overwintering larval of this pest, but which is still poorly understood. So the critical photoperiod for diapause induction in OFM and the age in day of larvae sensitive to diapause-inducting photoperiod were determined in the laboratory. The results indicated that OFM is a typical short-day type. The rate of larvae entered diapause >95% at photoperiod of 8L:16D, 10L:14D and 12L:12D, the critical photoperiod was 13.75L:10.25D at 20°C, the rate of larvae entered diapause>95% at photoperiod of 10L:14D and 12L:12D, the critical photoperiod was 13.68L:10.32D at 24°C. The age in different day of larvae show a degree of sensitivity when exposure to a diapause-inducing photoperiod, although there is no obvious critical point in time, but still the age in 5-8th day of larvae was more sensitive to diapause-inducting photoperiod, the percentage of diapause in larvae exposed to short photoperiod was signifiantly higher than that exposed to long photoperiod during this period. Source

Du Q.,Henan Mechanical and Electrical Engineering College | Ma F.,Sanmenxia Polytechnic
2011 International Conference on Electric Information and Control Engineering, ICEICE 2011 - Proceedings | Year: 2011

A research that the influence of combustion chamber's construction parameter on performance of diesel-natural gas dual fuel engine has been done, which is based on a dual fuel engine of diesel-natural gas. The heat release rate of dual fuel engine is calculated and analyzed via the indicated work diagrams of three kinds of different combustion chamber's structural parameter. The research results demonstrate that the shape of combustion chamber and the compression ratio has great effect on a dual fuel engine's combustion pressure, pressure rise rate and heat release rate etc. It has obvious effects on combustion process when increases compression ratio and reduces the caliber of combustion chamber properly. The replacement ratio of natural gas may be raised and the performances of dual fuel engine may be enhanced. © 2011 IEEE. Source

Shi Y.,Sanmenxia Polytechnic | Wang J.,Zhengzhou University of Light Industry
Journal of Surfactants and Detergents | Year: 2014

A novel zwitterionic surfactant N-dodecyl aspartic acid was synthesized with dodecylamine, maleic acid anhydride and sodium hydroxide in ethanol-water as the solvent. The chemical structure of N-dodecyl aspartic acid was characterized by IR, 1H NMR and MS. The surface properties of the surfactant were studied by measuring the equilibrium surface tensions of the dilute aqueous solutions. The synthesized surfactant can reduce the surface tension of water to 29-32 mN m-1 at temperatures of 298-313 K, the surface activity reaches its highest under mild pH conditions. The water hardness has almost no effect on foam power and foam stability of the surfactant at lower and middle water hardnesses. © 2014 AOCS. Source

Zheng J.,Sanmenxia Polytechnic
Applied Mechanics and Materials | Year: 2013

On the one hand, resource-based cities have played a great role to the economic growth of our country. On the other hand, they have also caused great destruction to China's economic development. The sustainable development evaluation of resource-based cities is a new topic, and its theory and method system remain to be discussed. Taking Pingdingshan City, Henan Province as an example, this paper discusses the evaluation method of sustainable development of resource-based cities. Combining the methods of scientific and practical, typical and comparable, dynamic and operable, comprehensive and hierarchical, taking AHP comprehensive evaluation as the foundation, from resource support ability, environment support ability, social support ability, and economic support ability, this evaluation method choose 47 index to evaluate the sustainable development of resource-based cities. The comprehensive evaluation index system of this paper strives to comprehensive reflect the process of sustainable development of resource-based cities, and hopes to provide some reference for policy making for the sustainable development of resource-based cities. © (2013) Trans Tech Publications, Switzerland. Source

He C.,Northwest University, China | Meng Q.-K.,Sanmenxia Polytechnic | Yang X.-B.,Northwest University, China | Hua L.,Northwest University, China
International Journal of Agriculture and Biology | Year: 2013

Oriental fruit moth, Grapholita molesta (Lepidoptera: Tortricidae), is a major pest of tree fruits worldwide, overwinters in mature larva diapause. However, little is known about the physiological explanation for diapause development in this pest. In this study, we analyzed the dynamic metabolic processes of carbohydrate, protein and antioxidant enzymes in diapausing larvae, which were maintained at low temperatures of 4 and 10°C under laboratory conditions, and 24°C as control for up to 4 months. After 100 days of maintenance, diapause could be terminated at low temperatures, as indicated by the pupation rate, the larvae were more conducive to complete diapause development at 10°C compared to 4°C. During diapause, total sugar and glycogen content decreased and trehalose content increased at low temperatures; glycerol content significantly increased at 4°C, but not at 10°C; protein content did not significantly changed at low temperature, but slightly decreased during the middle phase of diapause. Additionally, the activities of SOD and CAT increased and POD activities decreased during the middle phase of diapause at low temperatures. Our results indicate that temperature and diapause intensity significantly affected the carbohydrate content and antioxidant enzymes activities of the diapausing larvae, low temperature plays a predominant role in diapause termination, and antioxidant enzymes have a similar role in the regulation of energy metabolism as carbohydrate. © 2013 Friends Science Publishers. Source

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