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Spatial Variability of Soil Organic Carbon in Different Hillslope Positions in Toshan Area, Golestan Province, Iran: Geostatistical Approaches

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Journal of Mountain Science 2015年第6期12卷 1422-1433页

作者： Abolfazl BAMERI Farhad KHORMALI Farshad KIANI Amir Ahmad DEHGHANI dept. of Soil Science Gorgan University of Agricultural Sciences and Natural Resources dept. of Water engineering Gorgan University of Agricultural Sciences and Natural Resources

Accessibility to organic carbon(OC) budget is required for sustainable agricultural development and ecosystem preservation and restoration. Using geostatistical models to describe and demonstrate the spatial variability of soil organic carbon(SOC) will lead to a greater understanding of this dynamics. The aim of this paper is to present the relationships between the spatial variability of SOC and the topographic features by using geostatistical methods on a loess mountain-slope in Toshan region, Golestan Province, northern Iran. Hence, 234 soil samples were collected in a regular grid that covered different parts of the slope. The results showed that such factors as silt, clay, saturated moisture content, mean weighted diameter(MWD) and bulk density were all correlated to the OC content in different slope positions, and the spatial variability of SOC more to slope positions and elevations. The coefficient of variation(CV) indicated that the variability of SOC was moderate in different slope positions and for the mountain-slope as a whole. However, the higher variability of SOC(CV = 45.6%) was shown in the back-slope positions. Also, the ordinary cokriging method for clay as covariant gave better results in evaluating SOC for the whole slope with the RMSE value 0.2552 in comparison with the kriging and the inverse distance weighted(IDW) methods. The interpolation map of OC for the slope under investigation showed lowering SOC concentrations versus increasing elevation and slope gradient. The spatial correlation ratio was different between various slope positions and related to the topographic texture.

关键词： Geostatistics Loess Soil organic carbon(SOC) Slope position Spatial heterogeneity Topography

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Fuel ethanol production using novel carbon sources and fermentation medium optimization with response surface methodology

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International Journal of agricultural and biological engineering 2013年第2期6卷 42-53页

作者： Weihua Wu Department of biological and agricultural engineering University of CaliforniaDavisCA 95616USA

In this study,ethanol production abilities of the novel carbon sources:sodium and calcium gluconate in different minimal and rich media were compared with glucose using Escherichia coli *** strain produced higher ethanol yield in the rich medium Luria-Bertani(LB)than the other two minimal media:corn steep liquor(CSL)and M9 for two substrates(sodium and calcium gluconate).Additionally,higher ethanol yields were achieved when the strain was grown in LB and M9 medium with calcium gluconate than sodium gluconate,while the ethanol yields were similar when both sodium and calcium gluconate were added into CSL medium *** surface methodology was used to optimize the fermentation medium components for enhancing ethanol production using strain *** KO11 in CSL medium with calcium gluconate as the substrate in batch *** concentration of the potassium phosphate buffer is the only significant factor among five factors considered.A quadratic model was developed to describe the relationship between ethanol production and the *** optimal conditions predicted for five factors were 14.38 g/L CSL,0.0398 g/L FeCl_(3)·6H2O,1.12 g/L MgSO_(4)·6H_(2)O,15.41 g/L(NH4)_(2)SO_(4),and 1.58/1.26 g/L KH_(2)PO_(4)/K_(2)HPO_(4)(2:1 molar ratio).The highest ethanol concentration under optimal conditions was 31.5 g/L,which was 5.6 g/L higher than that from the same fermentation concentration of calcium gluconate in LB *** high correlation between the predicted and experimental values confirmed the validity of the model.

关键词： gluconate salts ethanol response surface methodology medium optimization biofuel

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Combined and synergistic effects of climate change and urbanization on water quality in the Wolf Bay watershed,southern Alabama

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Journal of Environmental Sciences 2018年第2期30卷 107-121页

作者： Ruoyu Wang Latif Kalin Purdue University Department of Agricultural and Biological Engineering Auburn University School of Forestry and Wildlife Sciences

This study investigated potential changes in flow, total suspended solid（TSS） and nutrient（nitrogen and phosphorous） loadings under future climate change, land use/cover（LULC）change and combined change scenarios in the Wolf Bay watershed, southern Alabama,USA. Four Global Circulation Models（GCMs） under three Special Report Emission Scenarios（SRES） of greenhouse gas were used to assess the future climate change（2016–2040）. Three projected LULC maps（2030） were employed to reflect different extents of urbanization in future. The individual, combined and synergistic impacts of LULC and climate change on water quantity/quality were analyzed by the Soil and Water Assessment Tool（SWAT）.Under the ＂climate change only＂ scenario, monthly distribution and projected variation of TSS are expected to follow a pattern similar to streamflow. Nutrients are influenced both by flow and management practices. The variation of Total Nitrogen（TN） and Total Phosphorous（TP） generally follow the flow trend as well. No evident difference in the N：P ratio was projected. Under the ＂LULC change only＂ scenario, TN was projected to decrease,mainly due to the shrinkage of croplands. TP will increase in fall and winter. The N：P ratio shows a strong decreasing potential. Under the ＂combined change＂ scenario, LULC and climate change effect were considered simultaneously. Results indicate that if future loadings are expected to increase/decrease under any individual scenario, then the combined change will intensify that trend. Conversely, if their effects are in opposite directions, an offsetting effect occurs. Science-based management practices are needed to reduce nutrient loadings to the Bay.

关键词： Climate change Urbanization Sediment Nutrients SWAT

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Artificial senses for characterization of food quality

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Journal of Bionic engineering 2004年第3期1卷 159-173页

作者： R.E. Lacey biological and agricultural engineering Department Texas A & M University USA

Food quality is of primary concern in the food industry and to the consumer. Systems that mimic human senses have been developed and applied to the characterization of food quality. The five primary senses are: vision, hearing, smell, taste and touch. In the characterization of food quality, people assess the samples sensorially and differentiate “good”from “bad”on a continuum. However, the human sensory system is subjective, with mental and physical inconsistencies, and needs time to work. Artificial senses such as machine vision, the electronic ear, electronic nose, electronic tongue, artificial mouth and even artificial the head have been developed that mimic the human senses. These artificial senses are coordinated individually or collectively by a pat- tern recognition technique, typically artificial neural networks, which have been developed based on studies of the mechanism of the human brain. Such a structure has been used to formulate methods for rapid characterization of food quality. This research presents and discusses individual artificial sensing systems. With the concept of multi-sensor data fusion these sensor systems can work collectively in some way. Two such fused systems, artificial mouth and artificial head, are described and discussed. It indicates that each of the individual systems has their own artificially sensing ability to differentiate food samples. It further indicates that with a more complete mimic of human intelligence the fused systems are more powerful than the individual sys- tems in differentiation of food samples.

关键词： food quality artificial senses quality quantification artificial neural networks feature extraction multi-sensor data fusion

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Coupling Effect of Morphology and Mechanical Properties Contributes to the Tribological Behaviors of Snake Scales

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Journal of Bionic engineering 2018年第3期15卷 481-493页

作者： Long Zheng Yinghui Zhong Yihang Gao Jiayi Li Zhihui Zhang Zhenning Liu Luquan Ren Key Laboratory of Bionic engineering (Ministry of Education) College of Biological and Agricultural Engineering Jilin University Changchun 130022 China

It is known that the tribological behaviors of snake skins are contributed by the synergistic action of multiple factors, such as surface morphology and mechanical properties, which has inspired fabrication of scale-like surface textures in recent years. However, the coupling effect and mechanism remain to be elucidated. In this work, the morphology and mechanical properties of the scales from different body sections （leading body half, middle trunk and tailing body half） and positions （dorsal, lateral and ventral） of Boa constrictor and Eryx tataricus were characterized and compared to investigate the corresponding effects on the tribological behaviors and to probe the possible coupling mechanism. The morphological characterizations of scanning electron microscopy and atomic force microscopy revealed sig- nificant differences between the two species that the scales from Boa constrictor are rougher in general. The mechanical properties measured by nanoindentation corroboratively demonstrated substantial differences in elastic modulus and hardness. Interestingly, the ventral scales with lower surface roughness, together with relatively larger elastic modulus and hardness, manifest higher friction coefficients. A ＂double-crossed＂ hypothesis was proposed to explain the observed coupling effect of morphology and mechanical properties on friction, which may afford valuable insights for the design of bionic surface with desirable tribological performance.

关键词： bionics coupling effect friction coefficient morphology mechanical properties snake scales

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Bionic Coupling of Hardness Gradient to Surface Texture for Improved Anti-wear Properties

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Journal of Bionic engineering 2016年第3期13卷 406-415页

作者： Long Zheng Jianjun Wu Si Zhang Shishuai Sun Zhihui Zhang Song Liang Zhenning Liu Luquan Ren Key Laboratory of Bionic engineering (Ministry of Education) College of Biological and Agricultural Engineering Jilin University Changchun 130022 China

This work investigates the potential of combining hardness gradient with surface texture （an example of bionic coupling） to improve anti-wear properties. The bionic coupling of hardness gradient and Hexagonal Texture （HT） was achieved by laser heat treatment on steel specimens with pre-engraved hexagonal surface texture. The successful establishment of decreasing hardness from surface to internal bulk was verified by hardness measurements along the dept. of cross-sectioned specimens and corre- lated with the observations from metallurgical microscopy. The tribological performance of bionic coupling specimens （HT-L） was examined under dry contact condition, together with respective control specimens of individual bionic features, e.g. HT-H （of similar surface hardness generated by conventional heat treatment but without hardness gradient） and SS-L （of smooth surface treated by the same laser processing as for HT-L）. It is found that HT-L not only exhibits lower friction coefficient and less friction fluctuation than HT-H and SS-L, but also demonstrates a 〉50% reduction of wear loss compared to HT-H and SS-L （0.0343 g for HT-L vs. 0.0723 g for HT-H, P〈0.001; 0.0343 g for HT-L vs. 0.0817 g for SS-L, P〈0.001）. Corroboratively, observations with scanning electron microscopy revealed a relatively smooth surface for worn HT-L specimen, contrasting with the rugged and grooved surfaces of worn HT-H and SS-L specimens. These results indicate that the bionic coupling of hardness gradient to hexagonal texture can indeed improve anti-wear properties, affording a new strategy to wear and friction manage- ment.

关键词： anti-wear bionic coupling hardness gradient surface texture hexagonal texture

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Plant vs. Animal Prototype for Designing Bio-inspired PEMFC Flow Fields: Corn Veins or Murray’s Law?

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Journal of Bionic engineering 2022年第3期19卷 761-776页

作者： Wenxuan Fan Taotao Zhao Ke Jiang Lei Sun Saisai Jia Qianqian Wu Guolong Lu Zhenning Liu Key Laboratory of Bionic engineering(Ministry of Education) College of Biological and Agricultural EngineeringJilin UniversityChangchun130022China

Designing bio-inspired flow fields holds great potential in improving the performance of Proton Exchange Membrane Fuel Cell(PEMFC).Two kinds of biological prototypes are widely used:plant prototype and animal *** remains a question which one of these prototypes is more appropriate for the scenario of ***,a comparative study was conducted to compare bionic flow fields based on animal and plant ***,a Corn Leaf Vein Mathematical Model(CLMM)was established by extracting structural parameters from corn leaves of two growth *** the obtained CLMM and well-known Murray’s law were employed to design bionic flow fields corresponding to the plant and animal prototypes,respectively,which have been subsequently compared by numerical *** results demonstrate that the flow field guided by Murray’s law outperforms the counterpart based on the structural parameters of CLMM in terms of PEMFC net output power,mass transport,water management and pressure drop,suggesting that animal circulation system is more suitable to the bionic flow field design of PEMFC than plant leaf *** work may also offer valuable insights into the design of other flow fields related to electrochemical energy conversion.

关键词： Proton exchange membrane fuel cell Flow field biological prototypes Corn leaf vein Murray’s law Comparative study

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Moisture absorption properties of biomimetic laminated boards made from cross-linking starch/maize stalk fiber

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International Journal of agricultural and biological engineering 2015年第2期8卷 65-71页

作者： Zhang Fu Wang Wei Tong Jin Zhou Jiang College of agricultural engineering Henan University of Science and TechnologyLuoyang 471003China College of biological and agricultural engineering Jilin UniversityChangchun 130025China

In the research,three kinds composite materials of biomimetic laminated boards made from cross-linking starch/maize stalk fiber-the single layer jute fiber reinforced maize stalk fiber boards,the dual layer jute fiber reinforced maize stalk fiber boards,the jute fiber hybrid reinforced maize stalk fiber boards were obtained according to the formulation of cross-linking maize starch adhesive and the preparation process of composite *** hygroscopicity variation of the biomimetic laminated boards made from cross-linking starch/maize stalk fiber was investigated under different relative humidity *** moisture absorption rate and the variation velocity were used as important evaluation indexes to evaluate the moisture absorption properties of the straw fiber *** mathematical models of the moisture absorption rate and the variation velocity were *** hygroscopicity variation curves of three kinds of composite materials were measured under the five different relative humidity *** results showed that the three kinds composites had low moisture absorption rate compared with other stalk fiber composites which were good at water resistance and the waterproof property of the three kinds stalk fibers were excellent under the experimental *** research provides a useful reference to improve the water resistance of fiber composites and a new idea on the development and application of the biodegradable composites,especially the straw fiber reinforced composites.

关键词： straw stalk fiber starch composite moisture absorption property laminated boards

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Design and Tests of Biomimetic Blades for Soil-rototilling and Stubble-breaking

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Journal of Bionic engineering 2015年第3期12卷 495-503页

作者： Jin Tong Wenfeng Ji Honglei Jia Donghui Chen Xiaowan Yang The Key Laboratory of Bionic engineering (Ministry of Education China) and the College of Biological and Agricultural Engineering Jilin University (Nanling Campus) Changchun 130022 China The College of engineering Huazhong Agricultural University Wuhan 430070 China

Biomimetic blades for soil-rototilling and stubble-breaking were designed learning from the geometrical structure of the tips of toes of mole rat （Scaptochirus moschatus）. The orientation, the number and the central angle of the biomimetic structure were taken as the testing factors. The optimal structure of the biomimetic blade was determined through the tests of soil-rototilling and stubble-breaking operation in an indoor soil bin. The optimal combination of the biomimetic structure pa- rameters is that three arc concave teeth are equally arranged on the front cutting edge with a central angle of 60°. The results of comparative tests between the optimal biomimetic blade and a conventional universal blade show the torque acting on the biomimetic blade is lower during soil-rototilling and stubble-breaking operations. The results of field tests show that the working quality of the biomimetic blades meets the requirements of the national standard of China. Tests of soil-rototilling show that, when the orientation of the biomimetic structure was at low and middle levels, the torque ofbiomimetic blades decreased from 34.17 N·m to 31.03 N·m. The torque also decreased with the increase of the number of biomimetic structure. The average torques were 34.57 N·m, 33.44 N·m and 31.37 N·m, respectively. The maximum different value between two levels of central angle was 0.41 N·m. Tests in field indicate that for soil-rototilling operation, the tillage dept. is deeper than 80 mm, the soil-crushing rate （length of soil block less than 40 mm） is over 50 %, and the vegetation coverage rate is over 55 %. For stubble-breaking operation, the stubble-breaking dept. is deeper than 70 ram, the stubble-breaking rate （length of stubble less than 40 mm） is over 60%, and the stubble coverage rate is over 80%, which can meet the stubble-breaking requirement of corn.

关键词： biomimetics mole rat (Scaptochirus moschatus) soil-rototilling stubble-breaking torque working quality

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DEM Numerical Simulation of Abrasive Wear Characteristics of a Bioinspired Ridged Surface

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Journal of Bionic engineering 2010年第2期7卷 175-181页

作者： Mohammad Almagzoub Mohammad Carlo Menon Key Laboratory of Bionic engineering Jilin University College of biological and agricultural engineering Jilin University MENRVA Group Simon Fraser University

This paper presents numerical investigations into a ridged surface whose design is inspired by the geometry of a Farrer’*** objective of the performed research is to assess if the proposed Bioinspired Ridged Surface (BRS) can potentiallyimprove wear resistance of soil-engaging components used in agricultural machinery and to validate numerical simulationsperformed using software based on the Discrete Element Method (DEM).The wear performance of the BRS is experimentallydetermined and also compared with a conventional flat *** size of soil particles and relative velocities between theabrasive sand and the testing surfaces are *** results show that the numerical simulations are in agreement withthe experimental results and support the hypothesis that abrasive wear is greatly reduced by substituting a conventional flatsurface with the BRS.

关键词： bioinspired ridged surface abrasive wear numerical simulation Discrete Element Method (DEM)

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