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Pedosphere 2010年第6期20卷 681-691页

作者： D.TARRASóN g.ojeda O.ORTIZ J.M.ALCAIZ Centre for Ecological Research and Forestry Applications Autonomous University of Barcelona IMAR-Coimbra Interdisciplinary Centre Department of ZoologyUniversity of Coimbra

The recycling of suitable organic wastes can enhance soil fertility via effects on soil physical, chemical and biological properties. To compare the effects of digested (DS), thermally dried (TDS) and composted dewatered (CDS) sewage sludge on soil microbiological properties, an experiment was conducted at field sites for more than one year (401 d) when applied to two Mediterranean degraded soils (loam and loamy sand soils). All three types of sewage sludge had a significant effect on measured parameters. In a short time, the plots of both loamy sand and loam soils amended with TDS showed the highest microbial basal respiration (loam soil: P ghest microbial metabolic quotient (qCO 2 ) (P ge caused transient non-equilibrium effects on almost all soil microbial properties. However, there were no differences one year later because the remaining organic carbon was stable and quite similar in all treatments. These results may have practical implications for the rehabilitation of degraded soils.

关键词：微生物特性土壤退化污水污泥地中海田间试验类型沙壤土微生物代谢

The challenging management of malignant ureteral obstruction:Analysis of a series of 188 cases

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Challenges and opportunities in the production of magnesium parts by directed energy deposition processes

Current Urology 2024年第1期18卷 34-42页

作者： Alberto Artiles Medina Inés Laso garcía Fernando gonzález Tello Sara Álvarez Rodríguez Manuel Hevia Palacios Marina Mata Alcaraz César Mínguez ojeda Fernando Arias Funez Victoria gómez Dos Santos Francisco Javier Burgos Revilla Department of Urology Hospital Universitario Ramón y CajalMadridSpain Department of Radiology Hospital Universitario Ramón y CajalMadridSpain

Background:Malignant ureteral obstruction(MUO)is a common condition that complicates the course of advanced *** aims of this study are to analyze the causes,management,and survival of patients with obstructive nephropathy due to malignant ureteric obstruction and to determine prognostic ***,we studied the complications and outcomes in patients who underwent urinary *** and methods:A retrospective study was conducted on patients with computed tomography-confirmed MUO between January 2016 and November ***,clinical,radiological,laboratory,and management data were *** curves were estimated using the Kaplan-Meier method,and univariate and multivariate Cox proportional hazards models were used to test the association between parameters and ***:A total of 188 patients were *** mean age was 69.01 years(SD,14.95 years),and the majority(54.8%)were *** most common mechanism leading to MUO was compression by a pelvic mass(36.9%),and the 3 most frequent tumors causing MUO were prostate(17.6%),bladder(16.5%),and rectal cancer(11.7%).Forty-seven patients(25%)underwent urinary diversion:23(48.9%)underwent double-J stenting and 21(44.7%)underwent percutaneous *** most common reason for urinary diversion was acute kidney injury(53.3%).Recovery of renal function was observed in 55.8%of the patients after urinary *** most frequently identified complications after urinary diversion were urinary tract infection(24.4%),hematuria(17.0%),and urinary sepsis(14.9%).The median survival after hydronephrosis diagnosis was 6.43 months(interquartile range,1.91-14.81 months).In patients who underwent urinary decompression,the median survival after urinary diversion was 8.67 months(interquartile range,2.99-17.28 months).In the multivariate analysis,a lower grade of hydronephrosis and cancer cachexia negatively impacted ***:Cancer patients with MUO have a poor pro

关键词： Hydronephrosis Ureteral obstruction Neoplasms Urinary diversion Survival Prognosis

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Journal of Magnesium and Alloys 2024年第5期12卷 1663-1686页

作者： gürel Cama Ali günen Iskenderun Technical University Faculty of Engineering and Natural SciencesDepartment of Mechanical Engineering31200˙Iskenderun-HatayTurkey Iskenderun Technical University Faculty of Engineering and Natural SciencesDepartment of Metallurgy and Materials Engineering31200 Iskenderun-HatayTurkey

Mg-alloys have gained considerable attention in recent years for their outstanding properties such as lightweight,high specific strength,and corrosion resistance,making them attractive for applications in medical,aerospace,automotive,and other transport ***,their widespread application is hindered by their low formability at room temperature due to limited slip *** Mg-alloys have low mechanical properties due to the presence of casting defects such as porosity and anisotropy in addition to the high *** casting methods benefit from established process optimization techniques for these problems,additive manufacturing methods are increasingly replacing casting methods in Mg alloys as they provide more precise control over the microstructure and allow specific grain orientations,potentially enabling easier optimization of anisotropy properties in certain *** metal additive manufacturing(MAM)technology also results in some manufacturing defects such as inhomogeneous microstructural evolution and porosity and additively manufactured Mg alloy parts exhibit lower properties than the wrought parts,they in general exhibit superior properties than the cast ***,MAM is a promising technique to produce Mg alloy *** energy deposition processes,particularly wire arc directed energy deposition(WA-DED),have emerged as an advantageous additive manufacturing(AM)technique for metallic materials including magnesium alloys,offering advantages such as high deposition rates,improved material efficiency,and reduced production costs compared to subtractive ***,the inherent challenges associated with magnesium,such as its high reactivity and susceptibility to oxidation,pose unique hurdles in the application of this *** review paper delves into the progress made in the application of DED technology to Mg-alloys,its challenges,and ***,the predominant imperfections,notably inhomo

关键词： Additive manufacturing DED processes Arc-DED Wire arc additive manufacturing(WAAM) 3-D printing High deposition rate

Recent research in mechanical properties of geopolymer-based ultrahigh-performance concrete:A review

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Defence Technology（防务技术） 2024年第2期32卷 67-88页

作者： g.Murali Division of Research&Innovation Uttaranchal UniversityDehradun 248007India

Due to the growing need for sustainable and ultra-high-strength construction materials,scientists have created an innovative ultra-high-performance concrete called geopolymer based ultra-highperformance concrete(gUHPC).Besides,in the last few decades,there have been a lot of explosions and ballistic attacks around the world,which have killed many civilians and fighters in border *** this context,this article reviews the fresh state and mechanical properties of ***,the ingredients of gUHPC and fresh properties such as setting time and flowability are briefly ***,the review of compressive strength,flexure strength,tensile strength and modulus of elasticity of fibrous ***,the blast and projectile impact resistance performance was ***,the microstructural characteristics were reviewed using the scanning electron microscope and X-ray Powder *** review outcome reveals that the mechanical properties were increased when 30%silica fume was added to a higher dose of steel fibre to improve the microstructure of *** is hypothesized that the brittleness of gUHPC was mitigated by adding 1.5%steel fibre reinforcement,which played a role in the decrease of contact explosion cratering and *** the need for cement in gUHPC was a key factor in the review,indicating a promising potential for lowering carbon ***,gUHPC research is still in its early stages,so more study is required before its full potential can be utilized.

关键词： Mechanical properties Blast Projectile impact Fibre geopolymer Silica fume Alkaline activators

Distribution and Relation of Primes with Tesla Numbers 3, 6, and 9

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Journal of Applied Mathematics and Physics 2024年第4期12卷 1021-1027页

作者： Javier Mendoza-Navarrete Huetzin Perez Ismael ojeda Victor Verdugo gabriel Luna Sandoval Ricardo Jimenez garcia Jaime Alvarez Departametno de Matemá ticas CBTis 256 DGETI Cabo San Lucas M&#233xico DCI Departamento de Fisica Mé dica Universidad de Guanajuato Leon M&#233xico Divisió n de Ingenieria en Sistemas Computacionales Tecnol&#243gico Nacional de M&#233xico ITES Los Cabos Cabo San Lucas M&#233xico Departamento de Ingenieria Industrial en Manufactura Universidad Estatal de Sonora Navojoa M&#233xico Departamento de Elé ctrica-Electr&#243nica Tecnol&#243gico Nacional de M&#233xico Campus Mexicali Mexicali M&#233xico guanajuato M&#233xico

This work presents a different approach to twin primes, an approach from the perspective of the Tesla numbers and gives a refresh and new observation of twin primes that could lead us to an answer to the Twin Prime Conjecture problem. We expose a peculiar relation between twin primes and the generation of prime numbers with Tesla numbers. Tesla numbers seem to be present in so many domains like time, vibration and frequency [1], and the space between twin primes is not the exception. Let us say that twin primes are more than just prime numbers plus 2 or minus 2, and Tesla numbers are more involved with twin primes than we think, and hopefully, this approach give us a better understanding of the distribution of the twin pairs.

关键词： Tesla Numbers Prime Number Twin Prime Numbers Twin Pair

Effects of frothers on bubbles size and flotation performance of hydrophobic minerals

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Journal of Central South University 2024年第7期31卷 2280-2299页

作者： gülşah gÜVEN Berivan TUNÇ ŞBeste AYDIN gülay BULUT Mineral Processing Engineering Department Faculty of MinesIstanbul Technical UniversityMaslak 34469IstanbulTurkey Research Center Metso OutotecKuparitie 1028101 PoriFinland

Frothers facilitate the reduction of bubbles size by preventing bubbles coalescence and produce more stable *** collision probability of the bubbles and particles substantially increases by decreasing bubble *** the same volume system,fewer bubbles result from a distribution of large-sized bubbles,and more bubbles result from a distribution of small-sized *** this research,fundamental two-phase frother characterization parameters were aimed to link with three-phase coal and talc flotation *** this purpose,the effect of single and dual frother systems on inhibiting bubble coalescence was investigated with methyl isobutyl carbinol(MIBC),isooctanol(2 ethyl hexanol),pine oil,and Dowfroth *** on the results of single frothers,isooctanol at the lowest critical coalescence concentration(CCC)value of 6×10^(−6) achieved the smallest bubbles with Sauter mean diameter of 0.80 *** blending Dowfroth 250 and pine oil,the bubbles size decreased significantly,reaching 0.45 *** the highest recoveries in coal flotation were obtained in single and frother blends where the bubbles size was measured as the smallest in two-phase system,and such a relationship was not found for talc flotation.

关键词： flotation frother blends bubble size coal and talc flotation

Nitrogen mineralization in the oldest climax communities in the eastern Mediterranean region

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Journal of Forestry Research 2024年第1期35卷 213-228页

作者： Fatma Selcen Sakar gürcan güleryüz Department of Biology Section Ecology GörükleGraduate School of Natural and Applied ScienceUniversity of Bursa Uludağ16059 NilüferBursaTurkey Department of Biology Section Ecology GörükleFaculty of Science and ArtsUniversity of Bursa Uludağ16059 NilüferBursaTurkey

In this study,we investigated how tree species affect N mineralization in connection to some soil properties and seconder metabolite levels of litter,in the soil of the old-est native forest *** the oldest pure communi-ties of Pinus nigra(PN),Fagus orientalis(FO),and Abies bornmuelleriana(AB)in the mountain range of Mount Uludağ,Bursa,Turkey,annual net yield and N mineraliza-tion in the 0-5-and 5-20-cm soil layers were determined in a field incubation study over 1 *** locations were chosen from 1300 to 1600 m a.s.l.,and moisture content(%),pH,water-holding capacity(%),organic C,total N,and C/N ratio,and annual net mineral N yield of the soil and hydro-lyzed tannic acid and total phenolic compounds in litter were compared for these forest *** had the highest annual net Nmin yield(43.9±4.8 kg ha^(-1) a^(-1)),*** the lowest(30.5±4.2 kg ha^(-1) a^(-1)).Our findings show that in the oldest forest ecosystems,the seasonal soil moisture content and tree species play an essential role in N cycling and that hydrolyzed tannic acids and total phenolic compounds effectively control N *** acid and total phenolics in the litter were found to inhibit nitrification,but total phenolics were found to stimulate ammonification.

关键词： Oldest forest communities Nitrogen mineralization Nitrification Tannic acid Total phenolic Litter

The Nikola Tesla Constant and Its Relation to the Circumference Inscribed in a Square

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Journal of Applied Mathematics and Physics 2024年第1期12卷 277-283页

作者： Javier Mendoza Navarrete José Ismael ojeda Campaña Huetzin Perez gabriel Luna-Sandoval Victor Verdugo Ricardo Jiménez garcia Departamento de Matemáticas CBTis 256 DGETI Cabo San Lucas México División de Ingeniería en Sistemas Computacionales Tecnológico Nacional de México/ITES de Los Cabos Cabo San Lucas México DCI Departamento de Física Médica Universidad de Guanajuato León México Departamento de Ingeniería Industrial en Manufactura Universidad Estatal de Sonora Navojoa México Departamento de Eléctrica-Electrónica Tecnológico Nacional de México Campus Mexicali Mexicali México

This research work relates the surface of a square and the area circumscribed by a circle, resulting in a value called Nikola Tesla constant. This constant starts with the calculation of the areas of the square and the inscribed circle, giving a ratio of 9/40 and from which a residual area of the area proportions of the geometric figures described is obtained. Plotting smooth curves, particularly those in round shapes, can be represented efficiently with the use of Nikola Tesla constant, reducing complex mathematical calculus.

关键词： Tesla Numbers Prime Number Circle Binary Area

Shell-model representations of the microscopic version of the Bohr–Mottelson collective model

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Communications in Theoretical Physics 2024年第8期76卷 81-92页

作者： H g ganev Joint Institute for Nuclear Research Dubna Russia Institute of Mechanics Bulgarian Academy of Sciences

The structure of the irreducible collective spaces of the group Sp（12, R）, which many-particle nuclear states are classified according to the chain Sp（12, R） ? U（6） ? SO（6） ? SUpn（3） ■SO（2） ? SO（3） of the proton–neutron symplectic model（PNSM）, is considered in detail. This chain of the PNSM was recently shown to correspond to a microscopic shell-model version of the Bohr–Mottelson collective model. The construction of the relevant shell-model representations of the Sp（12, R） group along this chain is considered for three nuclei with varying collective properties and from different mass regions. It is shown that the SUpn（3） basis states of the Sp（12, R） representations belonging to the SO（6） irreps with seniority υ ≥ υ0, with υ0denoting the maximal seniority SO（6） irrep contained in the Sp（12, R） bandhead, are always Pauli allowed, but organized in a different way into different SO（6） shells. This is in contrast to the case of filling the levels of the standard three-dimensional harmonic oscillator and using the plethysm operation. Although the SUpn（3） multiplets within υ < υ0are not all Pauli forbidden, it is safe to discard them. The results obtained in the present work are important for the practical application of the microscopic version of the Bohr–Mottelson collective model.

关键词： microscopic shell-model version of the Bohr-Mottelson model proton-neutron symplectic model shell-model representations Sp(12, R) dynamical algebra

Harmonics in the Squirrel Cage Induction Motor Analytic Calculation Part III: Influence on the Torque-speed Characteristic

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CES Transactions on Electrical Machines and Systems 2024年第1期8卷 86-102页

作者： g.Kovács the ganz Electric Works BudapestHungary

The harmonics that appear in the squirrel cage asynchronous machine have been discussed in great detail in the literature for a long time. However, the systematization of the phenomenon is still pending, so we made an attempt to fill this gap in the previous parts of our study by elaborating formulas for calculation of parasitic torques. It was a general demand among those who work in this field towards the author to verify his formulas with measurements. In the literature, it seems,only one detailed, purposeful series of measurements has been published so far, the purpose of which was to investigate the effect of the number of rotor slots on the torque-speed characteristic curve of the machine. The main goal of this study is to verify the correctness of the formulas by comparing them with the referred series of measurements. Relying on this, the expected synchronous parasitic torques were developed for the frequently used rotor slot numbers-as a design guide for the ***, together with our complete table for radial magnetic pull published in our previous work, the designer has all the principles, data and formulas available for the right number of rotor slots for his given machine and for the drive system. This brings this series of papers to an end.

关键词： Asynchronous parasitic torques Induction motor Squirrel cage rotor Space harmonics Synchronous parasitic torques