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Effects of geometric design of forest road and roadside vegetation on traffic noise reduction

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Journal of Forestry Research 2016年第2期27卷 463-468页

作者： Seyed Ata Ollah Hosseini Seyran Zandi Asghar fallah Mehran Nasiri Department of Forestry and Forest Economics Faculty of Natural Resources University of Tehran Department of Forestry Faculty of Natural Resources Sari University of Agricultural Sciences and Natural Resources Alborz Road Development and Construction Corporation Civil Engineers office

Geometric design of forest roads and design of their landscapes can reduce noise pollution and its harmful effects on human health. We investigated the effects of technical and biological parameters such as geometric road design and various roadside tree stands on reducing noise pollution according to the tree density and distance from roadway in Darabkola Forests, Sari, Iran. We recorded the noise generated by a car （Land Rover） relative to changes in longitudinal slope, horizontal curve radius and type of road pavement. We also measured noise levels according to roadside tree density and stand type （coniferous and hardwood） in 40 rectangular plots of three widths （25, 100 and 300 m） and 50 m length that were randomly demar- cated along forest roads. The changes in noise level were recorded using a decibel meter with an accuracy of q-1.5 dB and resolution of 0.1 dB. Noise levels were higher alongside unpaved roads than alongside paved roads. There was an inverse relationship between the measured noise level and horizontal curve radius. The rate of noise level on horizontal curve with a radius less than 30, 30-45 m and more than 45 m were 64.8, 70.8 and 75.9 dB, respectively. The noise level increased with the increasing longitudinal slope of the road. There was a significant difference between the noise level on slopes less than 3 % （67 dB） and 3-8 % （71.2 dB） in comparison with slopes greater than 8 % （77.8 dB）, （p 〈 0.05）. Pinus brutia L. reduced the noise level more （about 6 dB） in stands of 1/3 density of mixed hardwoods within 25 m from middle of the road. Careful design of geometric properties of forest roads as well as planting coniferous trees with hardwoods is a suitable solution for reducing noise pollution.

关键词： Forest road Noise pollution Noise level Vegetation Distribution

Regioselective ring opening of epoxides using NH_4SCN/silica sulfuric acid:An efficient approach for the synthesis of β-hydroxy thiocyanate under solvent-free conditions

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Chinese Chemical Letters 2008年第6期19卷 665-668页

作者： Ali R. Kiasat Maryam Zayadi Mehdi fallah Mehrjardi Chemistry Department College of ScienceShahid Chamran UniversityAhvaz 61357-4-3169Iran

Silica sulfuric acid was developed as a stable and efficient heterogeneous catalyst in organic synthesis. This solid acid catalyzed the regioselective ring opening of epoxides by thiocyanate anion to give thiocyanohydrins as key intermediates in agricultural and pharmaceutical chemistry in high yields under solvent-free conditions.

关键词： Silica sulfuric acid Thiocyanohydrins β-Hydroxy thiocyanate Epoxide Solvent-free

Pro-environmental analysis of farmers'concerns and behaviors towards soil conservation in central district of Sari County,Iran

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International Soil and Water Conservation Research 2017年第1期5卷 43-49页

作者： Masoud Bijani Ezatollah Ghazani Naser Valizadeh Negin fallah Haghighi Department of Agricultural Extension and Education College of AgricultureTarbiat Modares University(TMU)Tehran ***Iran Department of Agricultural Extension and Education College of AgricultureShiraz UniversityShirazIran Research Institute for New Technology Development Studies(RINTDS) Iranian Research Organization for Science and Technology(IROST)Tehran ***Iran

This study aimed to pro-environmentally analyze farmers'concerns and behaviors towards soil *** research was a descriptive,causal,and correlational and conducted through a survey *** study population consisted of all farmers at the central district of Sari county,Iran(N=9621).Based on the Cochran's formula,120 farmers were selected using stratified random *** instrument employed in this study was a questionnaire with its validity being confirmed by a number of academic experts and agriculture specialists and its reliability being proved using Cronbach's alpha coefficients in a pilot study(outside the scope of the current study).(0.66≤α≤0.90).The results of the analysis regarding the effects of independent variables on the variables"soil conservation behavior"and"soil conservation concern"indicated that,among the variables affecting these two variables,the variable"attitude towards soil conservation"was the most powerful predictor of"soil conservation concerns"and the variable"social pressures on soil conservation"predicted farmers'"soil conservation behaviors"***,the independent variables used in this research could predict 42% of the variance in terms of soil conservation concern and 21% of the variance in terms of soil conservation *** findings can be practical and appropriate for executive officials since,instead of making efforts to direct change the behavior,they can first focus on conceptual changes and persuasive changes like changing attitudes towards soil conservation.

关键词： Soil conservation behavior Soil conservation concern Farmers Sari County

Mixed-effects modeling for tree height prediction models of Oriental beech in the Hyrcanian forests

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Journal of Forestry Research 2018年第5期29卷 1195-1204页

作者： Siavash Kalbi Asghar fallah Pete Bettinger Shaban Shataee Rassoul Yousefpour Sari Agriculture and Natural Resource University SariMazandaran Iran Warnell School of Forestry and Natural Resources University of Georgia Athens GA USA Gorgan Agriculture and Natural Resource University Gorgan Golestan Iran Faculty of Environment and Natural Resources University of Freiburg Freiburg Germany

Height–diameter relationships are essential elements of forest assessment and modeling *** this work,two linear and eighteen nonlinear height–diameter equations were evaluated to find a local model for Oriental beech（Fagus orientalis Lipsky） in the Hyrcanian Forest in *** predictive performance of these models was first assessed by different evaluation criteria： adjusted R^2（R^2_（adj））,root mean square error（RMSE）,relative RMSE（%RMSE）,bias,and relative bias（%bias） *** best model was selected for use as the base mixed-effects *** parameters for test plots were estimated with different tree selection *** show that the Chapman–Richards model had better predictive ability in terms of adj R^2（0.81）,RMSE（3.7 m）,%RMSE（12.9）,bias（0.8）,%Bias（2.79） than the other ***,the calibration response,based on a selection of four trees from the sample plots,resulted in a reduction percentage for bias and RMSE of about 1.6–2.7%.Our results indicate that the calibrated model produced the most accurate results.

关键词： Random effects Tree height Calibration Sangdeh forest Chapman–Richards model Oriental beech

Al(HSO_4)_3/silica gel as a novel catalytic system for the ring opening of epoxides with thiocyanate anion under solvent-free conditions

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Chinese Chemical Letters 2010年第2期21卷 146-150页

作者： Ali Reza Kiasat Arash Mouradzadegun Somayeh Elahi Mehdi fallah-Mehrjardi Department of Chemistry College of ScienceShahid Chamran University

For the first time,metal hydrogen sulfates and phosphates/silica gel have been studied as efficient and powerful solid acid catalysts in the ring opening of epoxides with thiocyanate *** most significant result was obtained by Al(HSO4)3/SiO2which afforded the corresponding β-hydroxy thiocyanates under mild reaction conditions and in very short reaction *** cheapness, availability of the catalyst,ease of procedure and work-up make this method attractive for the organic synthesis.

关键词： Metal hydrogen sulfates Solid acid catalysts Ring opening of epoxides β-Hydroxy thiocyanates

Immobilized silver nanoparticles on silica gel as an efficient catalyst in nitroarene reduction

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Chinese Chemical Letters 2010年第9期21卷 1015-1019页

作者： Ali Reza Kiasat Roya Mirzajani Fakhri Ataeian Mehdi fallah-Mehrjardi Chemistry Department College of ScienceShahid Chamran University Marine Chemistry Department Khoramshahr Marine Science and Technology University

Nanoparticles have properties that can be fine-tuned by their size as well as ***,there is significant current interest in preparing nano-materials of small size dispersity and to arrange them in close-packed *** letter describes a way of synthesising silver nanoparticles and their protection to aggregate by silica *** combination of catalytic quantities of immobilized silver nanoparticles with reductive ability of NaBH_4 efficiently reduces aromatic nitroarenes to the corresponding amines in aqueous *** is that highly chemoselective reactions were achieved in the presence of other functional groups such as halogen and carboxylic acid *** silver particles immobilized on silica gel are stable in the presence of oxygen for several months.

关键词： Silver nanoparticle Reduction Aromatic nitro compounds Aromatic amines Sodium borohydride

The Effect of Variable Stator on Performance of a Highly Loaded Tandem Axial Flow Compressor Stage

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Journal of Thermal Science 2016年第3期25卷 223-230页

作者： Hamzeh Eshraghi Masoud Boroomand Abolghasem M.Tousi Mohammad Toude fallah Ali Mohammadi Department of Aerospace Engineering and Centre of excellence on computational aerospace engineering Amirkabir University of Technology Nanotechnology Research and Application Center Sabanci University

Increasing the aerodynamic load on compressor blades helps to obtain a higher pressure ratio in lower rotational speeds. Considering the high aerodynamic load effects and structural concerns in the design process, it is possible to obtain higher pressure ratios compared to conventional compressors. However, it must be noted that imposing higher aerodynamic loads results in higher loss coemcients and deteriorates the overall performance. To avoid the loss increase, the boundary layer quality must be studied carefully over the blade suction surface. Employment of advanced shaped airfoils （like CDAs）, slotted blades or other boundary layer control methods has helped the de- signers to use higher aerodynamic loads on compressor blades. Tandem cascade is a passive boundary layer control method, which is based on using the flow momentum to control the boundary layer on the suction surface and also to avoid the probable separation caused by higher aerodynamic loads. In fact, the front pressure side flow momentum helps to compensate the positive pressure gradient over the aft blade＇s suction side. Also, in compari- son to the single blade stators, tandem variable stators have more degrees of freedom, and this issue increases the possibility of finding enhanced conditions in the compressor off-design performance. In the current study, a 3D design procedure for an axial flow tandem compressor stage has been applied to design a highly loaded stage. Following, this design is numerically investigated using a CFD code and the stage characteristic map is reported. Also, the effect of various stator stagger angles on the compressor performance and especially on the compressor surge margin has been discussed. To validate the CFD method, another known compressor stage is presented and its performance is numerically investigated and the results are compared with available experimental results.

关键词： Compressor Stage Highly Loaded Performance Characteristic Tandem Variable Stator

Impact of land-use management on nitrogen transformation in a mountain forest ecosystem in the north of Iran

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Journal of Forestry Research 2013年第1期24卷 115-119页

作者： Maryam Asadiyan Seyed Mohammad Hojjati Mohammad reza Pourmajidian Asghar fallah Sari Agricultural Sciences and Natural Resources University Sari-Iran.

Soil inorganic N is one of the most important soil quality indexes, which may be influenced by land-use change. The historical conversion of land-use from native vegetation to agriculture resulted in sharp declines in soil N dynamics. This study was conducted to determine the soil inorganic N concentrations and net N mineralization rate in four common types of land-uses in the mountain forest area in the north of Iran, namely arable land, pine plantation, ash plantation, and beech stand. The soil samples were taken from top mineral soil layer （5 cm） in each site randomly （n=6） during August- September 2010. Beech stand and ash plantation showed significantly higher total nitrogen compared with arable land and pine plantation, while extractable NH4 ＋-N concentration was significantly greater in Beech stand compare to arable soils （p〈0.05）. No significantly difference was found in Net N mineralization, net nitrification and net ammonification rates among different land-uses. Results showed that net N mineralization and ammonification were occurred just in the soil of Ash plantation during the incubation time. Our findings suggested that conversion of Hyrcanian forests areas to pine plantation and agricultural land can disrupt soil natural activities and affect extremely soil quality.

关键词： soil quality net N mineralization nitrogen dynamic land use Hyrcanian forest Alandan.

Estimation of conservation value of myrtle(Myrtus communis)using a contingent valuation method:a case study in a Dooreh forest area,Lorestan Province,Iran

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Forest Ecosystems 2016年第1期3卷 26-36页

作者： Neda Amiri Seyed F.Emadian Asghar fallah Kamran Adeli Hamid Amirnejad department of forestry sari agricultural and natural resource universitySariIran department of forest sciences gorgan agricultural and natural resource universityGorganlran department of forestry college of natural resourcessari agricultural sciences and natural resources universitySariIran department of forestry faculty of agriculturaluniversity of lorestanlorestanIran department of agricultural economics sari agricultural and natural resource universitySariIran

Background： Around 2000 plant species occur naturally in Lorestan Province of which 250 species are medicinal and myrtle is one of them. Myrtle is a shrub whose leaves and fruits have medicinal value and thus, if managed and harvested properly, could produce sustained economic benefits. In recent years, however, over half of the myrtle site areas was destroyed, due to inappropriate management and excessive harvesting practices. Thus, coming up with a practical harvesting approach along with identifying those factors damaging the sites, seems to be very crucial. Methods： In our investigation, we calculated the conservation value per hectare of myrtle in the Dooreh forest area in Lorestan Province. Using the Contingent Valuation （CV） and Double Bounded Dichotomous Choice （DBDC） methods, we determined the willingness to pay （VVTP） for myrtle conservation. The VVTP was estimated with a Iogit model for which indices were obtained based on a maximum precision criterion. Results： The results showed that 86.67 per cent of people were willing to pay for the conservation of these myrtle sites. Average monthly WTP per family was calculated as $0.79. The annual conservation value in terms of WTP for the preservation of the myrtle sites in Dooreh was estimated as $102,525. Among the variables of the model presented, education had a positive impact, while the amount proposed for payment and family size had a negative impact on the WTP. Conclusions： Our estimate of the value of myrtle conservation should provide justification for policy makers and decision making bodies of natural resources to implement policies in order to conserve the natural sites of this species more effectively.

关键词： Conservation value Myrtle Contingent valuation method Double Bounded Dichotomous method Logit model