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A technical and socioeconomic approach to estimate forest residues as a feedstock for bioenergy in northern Mexico

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Forest Ecosystems 2019年第4期6卷 312-322页

作者： Guadalupe Carrasco-Diaz Gustavo Perez-Verdin Jonathan Escobar-Flores Marco Antonio Marquez-Linares instituto politecnico Nacional CIIDIR Dgo.

Background: Forest residues can be a feasible alternative for converting energy into fuels, electricity, or *** to other second-generation bioenergy sources, they do not compete for food, are relatively cheap,abundant in forest-rich areas, and more importantly their energy balance is close to zero. Biomass estimations can help design energy strategies to reduce fossil fuels dependency. Because of the land property distribution in Mexico,biomass estimations should consider not only the physical availability, but also the willingness of landowners to extract such raw ***: This study presents a methodological approach for evaluating the potential use of forest residues as a feedstock to generate bioenergy in northern Mexico. Remote sensing and field forest inventory were used to estimate the quantity and distribution of forest residues. In addition, a discrete choice analysis evaluated landowners’ preferences towards bioenergy development, including the most important factors that influence their willingness to extract their products and the expected *** and conclusions: Considering both physical and socio-economic aspects, results showed that about59,000 metric tons per year could be available in the study area. The vast majority of landowners surveyed are willing to extract forest residues, as long as they are presented with extraction plans with the highest income. However, many showed concerns about the environmental impacts this activity can have on soils,plants, and fauna. These results can help evaluate the potential of these resources for bioenergy development.

关键词： Bioenergy Choice experiments Forest landowners Forest residues Remote sensing

Equivalence of a Bit Pixel Image to a Quantum Pixel Image

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Communications in Theoretical Physics 2015年第11期64卷 501-506页

作者： Carlos Ortega Laurel DONG Shi-Hai M.Cruz-Irisson ESIME-Culhuacan Instituto Politicnico Nacional CIDETEC Instituto Politecnico NacionalUPALM

We propose a new method to transform a pixel image to the corresponding quantum-pixel using a qubit per pixel to represent each pixels classical weight in a quantum image matrix *** qubits are linear superposition,changing the coefficients level by level to the entire longitude of the gray scale with respect to the base states of the ***,these states are just bytes represented in a binary matrix,having code combinations of 1 or 0 at all pixel *** method introduces a qubit-pixel image representation of images captured by classical optoelectronic methods.

关键词： qubit pixel quantum image processing image represe

Spatial heterogeneity of factors influencing forest fires size in northern Mexico

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Journal of Forestry Research 2014年第2期25卷 291-300页

作者： Gustavo Perez-Verdin Marco Antonio Marquez-Linares Maricela Salmeron-Macias instituto politecnico Nacional CIIDIR–DGODurangoDgoMexico34220

In Mexico, forest fires are strongly influenced by environmental, topographic, and anthropogenic factors. A government-based database covering the period 2000-2011 was used to analyze the spatial heterogeneity of the factors influencing forest fire size in the state of Durango, Mexico. Ordinary least squares and geographically weighted regression models were fit to identify the main factors as well as their spatial influence on fire size. Results indicate that fire size is greatly affected by distance to roads, distance to towns, precipitation, temperature, and a population gravity index. The geographically weighted model was better than the ordinary least squares model. The improvement of the former is due to the influence of factors that were found to be non-stationary. These results suggest that geographic location determines the influence of a factor on fire size. While the models can be greatly improved with additional information, the study suggests the need to adopt fire management policies to more efficiently reduce the effect of anthropogenic factors. These policies may include more training for landowners who use fire for clearing, closure of roads, application of thinning, prescribed burning, and fire breaks in perimeters adjacent to roads.

关键词： Durango Mexico geographically weighted regression ordinary least squares stationarity

Explicit Relations of Physical Potentials Through Generalized Hypervirial and Kramers' Recurrence Relations

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Communications in Theoretical Physics 2015年第6期63卷 682-686页

作者：孙国华董世海 Catedra CONACyT Centro de Investigacion en ComputacionInstituto Politecnico Nacional Departamento de Fisica Escuela Superior de Ffsica y MatematicasInstituto Politecnico Nacional

Based on a Hamfltonian identity, we study one-dimensional generalized hypervirial theorem, Blanchardlike （non-diagonal case） and Kramers＇（diagonal case） recurrence relations for arbitrary x^k which is independent of the central potential V（x）. Some significant results in diagonal case are obtained for special k in xk （k ≥2）. In particular, we find the orthogonal relation 〈n1｜n2〉 = δh1,n2 （k = 0）, 〈n1[V＇（x）｜n2〉 = （En1-En2）^2〈n1｜x｜n2〉（k = 1）, En = （n｜V＇（x）x/2｜n〉＋（n｜V（x）｜n〉（k = 2） and -4En（n｜x｜n） ~ 〈n｜V＇（x）x^2｜n〉＋ 4〈n｜V（x）x｜n〉 =0 （k=3）. The latter two formulas can be used directly to calculate the energy levels. We present useYul explicit relations for some well known physical potentials without requiring the energy spectra of quantum system.

关键词： Hamiltonian identity hypervirial relations Kramers' recurrence relation physical potentials

Tetrapartite entanglem ent features of W-C lass state in uniform acceleration

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Frontiers of physics 2020年第1期15卷 1-8页

作者： Qian Dong Ariadna J.Torres-Arenas Guo-Hua Sun Shi-Hai Dong Laboratorio de Informacion Cuantica CIDETECInstituto Politecnico NacionalUPALMCDMX 07700Mexico Catedratica CONACyT Centro de Investigacion en ComputacionInstituto Politecnico NacionalUPALMCDMX 07738Mexico

Using the single-mode approximatiou,we first calculate entanglement measures such as negativity(1-3 and 11 tangles)and von Neumann entropy for a tetrapartite W-Class system in noninertial fiarne and then anal^e the whole entanglement measures,the residualπ4 and geometricП4 average of *** that the difference betweenπ4 andП4 is very small or disappears with the increasing accelerated *** entanglement properties are compared among the different cases from oue accelerated observer to four accelerated *** results show that there still exists entanglement for the complete system even when accelemtion r tends to *** degree of entanglement is disappeared for the 1-1 tangle case when the acceleration r>*** reexamine the Unriih effect in noninertiai *** is shown that the entanglement system in which only one qubit is accelerated is more robust than those eutangled systems in whicli two or three or four qubits are *** is also found that the von Neumann entropy S of the total system always increases with the increasing accelerated observers,but the Sκξand Sκζδwith two and three involved noniuertial qubits first increases and then decreases with the acceleration parameter r,but they are equal to constants 1 and 0.811278 respectively for zero involved iioniiiertial qubit.

关键词： tetrapartite W-Class state entanglement Dirac field noninertiai frames

Optimal distribution of active piezoelectric elements for noise attenuation in sandwich panels

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International Journal of Smart and Nano Materials 2020年第4期11卷 400-416页

作者： J.F.A.Madeira A.L.Araujo IDMEC Instituto Superior TecnicoUniversidade de LisboaLisboaPortugal ADM ISELInstituto Politecnico de LisboaLisboaPortugal

In this paper,a multiobjective optimization approach for obtaining the optimal distribution of surface-bonded piezoelectric sensors and actua-tors for noise attenuation in sandwich panels is *** noise attenuation is achieved by using negative velocity feedback control with co-located sensors and *** control gains are also optimized in order to obtain the most efficient noise attenuation in a given frequency *** in-house implementation of a viscoelastic soft core sandwich plate finite element,including surface-bonded piezoelectric sensors and actuators with active control capabilities,is used for obtaining the frequency response of the *** sound transmission capability of the panels is evaluated using the radiated sound power,along with the Rayleigh integral approach,which is suitable for lightly coupled structural/acoustic *** Direct MultiSearch(DMS)optimization algorithm is used to minimize the added weight due to the piezoelectric material,minimizing also the number of required controllers and maximizing the noise *** total length of the radiated sound power curve is shown to be an effective measure of noise attenuation in a given frequency ***-off Pareto fronts and the obtained optimal configurations are presented and discussed.

关键词： Sandwich structures piezoelectricity viscoelasticity active damping multiobjective optimization

Dynamics of ^(14)C-labelled Glucose and NH_4^+ in a Regularly Flooded Extremely Alkaline Saline Soil

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Pedosphere 2015年第2期25卷 230-239页

作者： Luc DENDOOVEN Eustacio RAMIREZ-FUENTES Rocio ALCANTARA-HERNDEZ Cesar VALENZUELA-ENCINAS Katia Berenice SANCHEZ-LOPEZ Marco LUNA-GUIDO Victor Manuel RUIZ-VALDIVIEZO Laboratory of Soil Ecology ABACUSCinvestavAvenida Instituto Politecnico Nacional 2508CP 07360Mexico Mexico

Flooding an extremely alkaline(pH 10.6) saline soil of the former Lake Texcoco to reduce salinity will affect the soil carbon(C)and nitrogen(N) dynamics.A laboratory incubation experiment was done to investigate how decreasing soil salt content affected dynamics of C and N in an extremely alkaline saline *** soil with electrical conductivity(EC) of 59.2 dS m^(-1) was packed in columns,and then flooded with tap water,drained freely and conditioned aerobically at 50%water holding capacity for a *** process of flooding-drainage-conditioning was repeated eight *** original soil and the soil that had undergone one,two,four and eight flooding-drainage-conditioning cycles were amended with 1000 mg glucose-^(14)C kg^(-1) soil and 200 mg NH_4^+-N kg^(-1)soil,and then incubated for 28 *** CO_2 emissions,soil microbial biomass,and soil ammonium(NE_4^+),nitrite(NO_2^-) and nitrate(NO_3^-) were monitored in the aerobic incubation of 28 *** soil EC decreased from 59.2 to 1.0 dS m^(_1) after eight floodings,and soil pH decreased from 10.6 to *** the added ^(14)C-labelled glucose,only 8%was mineralized in the original soil,while 24%in the soil flooded eight times during the 28-d *** priming effect was on average 278 mg C kg^(-1) soil after the 28-d *** microbial biomass C(mean 66 mg C kg^(-1) soil) did not change with flooding times in the unamended soil,and increased 1.4 times in the glucose-NH_4^+-amended *** immobilization and NO_2^- concentration in the aerobically incubated soil decreased with increasing flooding times,while NO_3^- concentration *** was found that flooding the Texcoco soil decreased the EC sharply,increased mineralization of glucose,stimulated nitrification,and reduced immobilization of inorganic N,but did not affect soil microbial biomass C.

关键词： C mineralization CO2 emission microbial biomass C mineral N nitrification

ntegrated approach to winery waste： waste generation and data consolidation

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Frontiers of Environmental Science & Engineering 2016年第1期10卷 168-176页

作者： Margarida OLIVEIRA Elizabeth DUARTE instituto Superior de Agronomia (ISA) University of Lisbon 1349-017 Lisboa Portugal Escola Superior Agrairia de Santarem (ESAS) Instituto Superior Politecnico de Santarem 2001-904 Santarem Portugal

The winemaking process involves the genera- tion of a significant amount of waste and wastewater. These residues should be addressed for recycling or treatment before being returned to environment. As each winery is unique in waste generation and disposal, plans for environmentally friendly waste management are not universal and should be tested for their effectiveness. In this study, a diagnostic was made during three years, in different wineries, throughout Portugal, in order to quantify and characterize the waste and the wastewater produced. The results showed that solid waste and wastewater are mainly produced during the harvest period, corresponding to 74% and 87%, respectively. One ton of processed grape approximately produce 0.13 t marc, 0.06 t lees, 0.03 t of stalks and 1.65 m3 of wastewater. No significant differences （P≤0.05） were observed for grape marc, lees and wastewater ratios, between years or wineries. With respect to the stalk ratio, there was no effect of year but the winery significantly affected this ratio （P ≤ 0.05）. During the study period the treated wastewater, since diluted, revealed suitable characteristics for irrigation representing an additional source of water. In this regard, the data acquisition and consolidation ensure the transfer of information and experience which constitute an essential step in a support decision tool design.

关键词： waste management wastewater reuse winerywastewater

Phase separation and coarsening of NiAl(β′)intermetallic in quench-aged Fe-Ni-Al alloys

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Journal of Iron and Steel Research International 2020年第11期27卷 1331-1338页

作者： C.Ferreira-Palma J.A.Rosas-Barrios V.M.Lopez-Hirata D.I.Rivas-Lopez H.J.Dorantes-Rosales Faculty of Chemical Sciences Universidad VeracruzanaVeracruz 94294Mexico ESIQIE Instituto Politecnico Nacional.UPALMMexico City 07738Mexico

The coarsening behavior of four quench-aged Fe-Ni-AI alloys with different Ni and Al con tents is *** alloys were solubilized at 1100℃for 24 h,water-quenched and aged at 850℃for periods ranging from 1 to 100 h to promote phase separation and *** two alloys with the highest combined Ni and Al contents(>35 at.%)showed signs of spinodal decomposition,while the alloys with lower Ni and Al contents followed a classical nucleation *** Ni and Al contents promoted an increase in NiAl(β′)phase fraction in concordance with phase equilibrium *** alloy with the highest[3'fraction presented a completely interconnected *** coarsening ofβ′particles in the other three alloys followed the predictions of the Lifshitz-Slyozov-Wagner(LSW)*** general trend was an increase in the coarsening kinetics with higher Ni and Al *** highest hardness was found in the alloys with higher fraction albeit these compositions are less resistant to coarsening and have been reported to present a low room-temperature ductility.

关键词： Precipitation Spinodal decomposition Coarsening Aging Fe-Ni-Al alloy