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“城市矿产”资源产生及其供给潜力:以金属铌为例

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中国科学：地球科学 2024年第8期54卷 2625-2632页

作者：曾现来 Moisés GÓMEZ mahmoud bakry 耿涌李金惠清华大学环境学院北京100084 上海交通大学环境科学与工程学院上海200240 上海交通大学国际与公共事务学院上海200030

“碳中和”战略正在重塑全球资源流动和循环利用的格局,迅速增长的“城市矿产”(也称为二次资源)作为地质矿产的延伸,在资源供给和平衡方面发挥着越来越重要的作用.铌是一种关键金属,但目前缺乏对其可持续性的研究.循环利用的基本原则... 详细信息

“碳中和”战略正在重塑全球资源流动和循环利用的格局,迅速增长的“城市矿产”(也称为二次资源)作为地质矿产的延伸,在资源供给和平衡方面发挥着越来越重要的作用.铌是一种关键金属,但目前缺乏对其可持续性的研究.循环利用的基本原则是尽可能的在其全生命周期过程中高效利用该金属,对此,我们评估了含铌材料在报废过程中的损耗,揭示了最大限度减少此类损耗的必要性,阐明了全生命周期中含“城市矿产”和合金的利用过程.根据对大多数铌应用产生的“城市矿产”预测,如果不进行回收利用,到2090年可能会损失16.8万吨.相反,如果金属铌的回收利用率增至90%,预计其损失将减少到1.6万吨.因此,需要探索各种措施,以实现从线性经济到循环经济的无缝过渡,促进铌资源的可持续利用.

关键词：铌 “城市矿产” 循环经济回收利用可持续性

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Evaluation of global niobium flow modeling and its market forecasting

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Frontiers in Energy 2023年第2期17卷 286-293页

作者： mahmoud bakry Jinhui LI Xianlai ZENG School of Environment Tsinghua UniversityBeijing 100084China

Metal,as the indispensable material,is functioning the society from technology to the ***(Nb)is considered a unique earth metal as it is related to many emerging *** increasing economic growth exerts an increasing pressure on supply,which leads to its significance in the economic ***,few papers have addressed Nb sustainability,which forms the scope of this paper in order to start the process of Nb market forecasting based on some previous data and some ***,this paper will discuss different thoughts in material substitution and the substance flow of Nb throughout a static flow using Nb global data to have a better understanding of the process of Nb from production to end of *** shall lead to the identification of the market needs to determine its growth which is around 2.5% to 3.0%.Moreover,due to China’s huge Nb consumption which comes from the continuous development that is happening over the years,it will also briefly mention the Nb situation as well as its growth which according to statistics will grow steadily till 2030 by a rate of 4.0% to 6.0%.The results show that there should be some enhancement to Nb recycling potentials out of steel *** addition,there should be more involvement of Nb in different industries as this would lead to less-used materials which can be translated to less environmental impact.

关键词： niobium(Nb) sustainability substance flow analysis recycling industrial ecology

Applying MILP for 27-Level CMLIs to Obtain Low THD Values over Wide Voltage Range

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Energy and Power Engineering 2013年第4期5卷 315-321页

作者： mahmoud El-bakry Electronics Research Institute Giza Egypt

The 27-level cascaded multilevel inverter (CMLI) is a popular CMLI, since it can produce an output voltage with nearly sinusoidal wave form and may be realized as a trinary asymmetric CMLI that consists of only three H-bridges. A new approach using a mixed integer linear programming (MILP) model is applied, that can determine the switching angles of this CMLI that minimize the values of any undesired harmonics. The model is applied first to determine the number of harmonics to be minimized to obtain least percentage total harmonic distortion (%THD) utilizing the 13 positive levels of the inverter. The obtained result is then included in the model and it is solved for different values of the output voltage. Single phase and three phase cases are investigated. The results show very low values of %THD and low order harmonics over wide voltage range till the 91st harmonic in both cases, which agree with the IEEE standards 519-1992 for voltage distortion limits till 161 kv.

关键词： Cascaded Multilevel Inverters Harmonic Elimination Harmonic Values Minimization Mixed Integer Linear Programming Total Harmonic Distortion

Effectiveness of biofertilizers foliar application on yield and quality traits of flax(Linum usitatissimum L.)

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Oil Crop Science 2024年第2期9卷 91-101页

作者： Saied El Sayed A.B.bakry O.A.Nofal M.A.Abo Horish Plant Nutrition Department National Research Centre33 El-Behouth St12622DokkiCairoEgypt Field Crops Department National Research Centre33 El-Behouth St12622DokkiCairoEgypt

Flax is considered to be one of the most significant dual-purpose crops for oil and fiber production in Egypt and *** have a substantial impact on various metabolic processes,including increased photo-synthesis,endogenous hormone levels,ion absorption,nucleic acid synthesis,and protein *** factors collectively contribute to the growth and development of ***,this study aims to investigate how three biofertilizers(Algae extract,CMS as a by-product of yeast,and Metalosate multi minerals as amino acids)can enhance both the quantity and quality of flax seed yield under sandy soil *** field experiments were conducted at the Experimental Station of National Research Centre in Nubaria District,Behira Governorate,Egypt during two seasons(2021/2022)using a randomized complete block design(RCBD).The results revealed significant differences among all tested biofertilizers in terms of various characteristics studied in *** application of algae extract at a rate of 1.50 mL/L resulted in an increase in seed yield(ton/ha)by 26.69%&19.89%,straw yield(ton/ha)by 8.08%&17.12%,and oil yield(kg/ha)by 47.72%&33.69%compared to the control group during both seasons *** applications of algae extract at a rate of 1.50 mL/L along with CMS at a rate of 5 m L/L and amino acids at a rate of 1.50 mL/L demonstrated significantly higher macronutrient contents(N,P,K),micronutrient contents(Fe,Zn,Mn),seed oil content,and protein content in flax seeds during both *** highest values for seed oil content and protein content%were obtained through foliar application of amino acids at a rate of 1.50 mL/*** can be concluded that foliar sprays with these bio-fertilizers effectively improved flax performance by increasing seed straw and oil yields,nutrients oil,protein and fatty acids seeds contents.

关键词： Flax Bio fertilizers Seeds yield Nutrient contents Quality

Sodium nitroprusside as a signal molecule for up-regulating membrane characteristics, antioxidant defense system to improve flax productivity under water stress

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Oil Crop Science 2024年第3期9卷 160-169页

作者： Al-Ashkar N.M. bakry B.A. El-Bassiouny H.M.S. Abdallah M.M.S. Sadak M.S. Botany Department Agricultural and Biological Research Institute National Research Centre 33 El Bohouth Street P.O. 12622 Dokki Giza Egypt Field Crops Research Department Agricultural and Biological Research Institute National Research Centre 33 El Bohouth Street P.O. 12622 Dokki Giza Egypt

Water stress is a critical environmental adversity that significantly impacts the growth, development, and yield of flax plants. In this study, flax seeds were cultivated under different water irrigation requirements (WIR) (100%, 75%, and 50%) to investigate the effects of exogenously supplied nitric oxide (NO) donor sodium nitroprusside (SNP) as foliar treatments at concentrations of 0.0 mmol/L, 0.5 mmol/L, 1.0 mmol/L, and 2.0 mmol/L. Drought stress led to a significant decrease in plant growth, photosynthetic pigments, yield components such as oil and total carbohydrate percentage. It also resulted in an increase in leaf H2O2 production, lipid peroxidation levels and activities of enzymatic antioxidants including polyphenol oxidase, superoxide dismutase, and nitrate reductase enzymes. However, foliar application of SNP improved photosynthetic pigments and antioxidant defense system which mitigated the negative impact of water stress on growth and yield productivity by reducing oxidative damage caused by reactive oxygen species accumulation. The use of SNP also decreased H2O2 accumulation levels, lipid peroxidation levels, and improved membrane stability. SNP treatment at concentration of 2 mmol/L showed superior results compared to other concentrations with extremely significant increases observed in yield characteristics such as oil content, total carbohydrate percentages, and unsaturated fatty acids to saturated fatty acids ratio. © 2024 the Oil Crop Research Institute, Chinese Academy of Agriculture Sciences

关键词： Antioxidant enzymes Fatty acid Flax Sodium nitroprusside Yield

Sodium nitroprusside as a signal molecule for up-regulating membrane characteristics,antioxidant defense system to improve flax productivity under water stress

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Oil Crop Science 2024年第03期 160-169页

作者： N.M.Al-Ashkar B.A.bakry H.M.S.El-Bassiouny M.M.S.Abdallah M.S.Sadak Botany Department Agricultural and Biological Research Institute National Research Centre Field Crops Research Department Agricultural and Biological Research Institute National Research Centre

Water stress is a critical environmental adversity that significantly impacts the growth, development, and yield of flax plants. In this study, flax seeds were cultivated under different water irrigation requirements（WIR）(100%,75%, and 50%) to investigate the effects of exogenously supplied nitric oxide（NO） donor sodium nitroprusside（SNP） as foliar treatments at concentrations of 0.0 mmol/L, 0.5 mmol/L, 1.0 mmol/L, and 2.0 mmol/L. Drought stress led to a significant decrease in plant growth, photosynthetic pigments, yield components such as oil and total carbohydrate percentage. It also resulted in an increase in leaf H2O2production, lipid peroxidation levels and activities of enzymatic antioxidants including polyphenol oxidase, superoxide dismutase, and nitrate reductase enzymes. However, foliar application of SNP improved photosynthetic pigments and antioxidant defense system which mitigated the negative impact of water stress on growth and yield productivity by reducing oxidative damage caused by reactive oxygen species accumulation. The use of SNP also decreased H2O2accumulation levels, lipid peroxidation levels, and improved membrane stability. SNP treatment at concentration of 2 mmol/L showed superior results compared to other concentrations with extremely significant increases observed in yield characteristics such as oil content, total carbohydrate percentages, and unsaturated fatty acids to saturated fatty acids ratio.

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A FAST FREE MEMORY METHOD FOR AN EFFICIENT COMPUTATION OF CONVOLUTION KERNELS

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Journal of Computational Mathematics 2023年第6期41卷 1093-1116页

作者： Matthieu Aussal Marc bakry Ecole Polytechnique(CMAP) INRIAInstitut Polytechnique ParisRoute de Saclay 91128PalaiseauFrance

We introduce the Fast Free Memory method(FFM),a new implementation of the Fast Multipole Method(FMM)for the evaluation of convolution *** FFM aims at being easier to implement while maintaining a high level of performance,capable of handling industrially-sized *** FFM avoids the implementation of a recursive tree and is a kernel independent *** give the algorithm and the relevant complexity *** quasi-linear complexity enables the evaluation of convolution products with up to one billion *** illustrate numerically the capacities of the FFM by solving Boundary Integral Equations problems featuring dozen of millions of *** implementation is made freely available under the GPL 3.0 license within the Gypsilab framework.

关键词： Convolution product Fast multipole method Boundary integral equations Open-source

Heterogeneous performance analysis of the new model of CFAR detectors for partially-correlated χ~2-targets

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Journal of Systems Engineering and Electronics 2018年第1期29卷 1-17页

作者： EL_MASHADE Mohamed bakry Electrical Engineering Department Faculty of Engineering Al Azhar University

To mitigate the deleterious effects of clutter and jammer, modern radars have adopted adaptive processing techniques such as constant false alarm rate(CFAR) detectors which are widely used to prevent clutter and noise interference from saturating the radar’s display and preventing targets from being *** paper concerns with the detection analysis of the novel version of CFAR schemes(cell-averaging generalized trimmed-mean,CATM) in the presence of additional outlying targets other than the target under research. The spurious targets as well as the tested one are assumed to be fluctuating in accordance with the χ~2-model with two-degrees of freedom. In this situation, the processor performance is enclosed by the swerling models(SWI and SWII). Between these bounds, there is an important class of target fluctuation which is known as moderately fluctuating targets. The detection of this class has many practical applications. Structure of the CATM detector is described briefly. Detection performances for optimal, CAM, CA, trimmed-mean(TM) and ordered-statistic(OS) CFAR strategies have been analyzed and compared for desired probability of false alarm and determined size of the reference window. False alarm rate performance of these processors has been evaluated for different strengths of interfering signal and the effect of correlation among the target returns on the detection and false alarm performances has also been studied. Our numerical results show that, with a proper choice of trimming parameters,the novel model CAM presents an ideal detection performance outweighing that of the Neyman-Pearson detector on condition that the tested target obeys the SWII model in its fluctuation. Although the new models CAS and CAM can be treated as special cases of the CATM algorithm, their multi-target performance is modest even it has an enhancement relative to that of the classical CAcheme. Additionally, they fail to maintain the false alarm rate constant when the operati

关键词： adaptive target detection multi-pulse performance noise and interference partially-correlated χ~2-targets SWI & SWII target fluctuation models target multiplicity environments

Potassium and Zinc in Relation to Improve Flax Varieties Yield and Yield Components as Grown under Sandy Soil Conditions

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Agricultural Sciences 2015年第1期6卷 152-158页

作者： bakry Ahmed bakry Osama Anour Nofal Mohamed Soliman Zeidan mahmoud Hozayn Field Crops Department National Research Centre Cairo Egypt Plant Nutrition Department National Research Centre Cairo Egypt

Two field experiments were carried out at the experimental station of National Research Centre, Al-Nubaria District, El-Behira Governorate, Egypt during winter seasons of 2011/2012 and 2012/2013 to study the effect of potassium soil application at the rates (0, 50, 75 and 100 kg/fed.) with or without chelated zinc foliar application 5% at the rate of (0.03 kg/fed.) on the yield and quality of two flax varieties (Sakha-2 and Amon) in newly reclaimed sandy soil. The obtained results could be summarized as follow: Sakha-2 variety significantly surpassed Amon in plant height, technical length, number of branches/plant, seed yield/plant, straw yield/plant, 1000 seed weight, seed yield/fed., straw yield/fed., fiber %, fiber yield/fed. and oil yield/fed. Amon variety surpassed Sakha-2 in fruiting zone length, number of capsules/plant and oil % in both seasons. Potassium soil application at the rate of (100 kg/fed.) with chelated zinc foliar application 5% at the rate of (0.03 kg/fed.) gave the highest value for all studied characters.

关键词： Flax Potassium Fertilizer Zinc Fertilizer