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On the γ_n-complete Hypergroups and K_H Hypergroups

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Acta mathematica Sinica,English Series 2008年第11期24卷 1901-1908页

作者： Bijan DAVVAZ m.KARimiAN Department of mathematics Yazd University Yazd Iran

The class of γn-complete hypergroups is introduced. Several properties and examples are found both of γn-complete hypergroups and of KH hypergroups.

关键词： γ relation γn-complete hypergroup KH hypergroup γ-part

A LiOUViLLE THEOREm FOR STATiONARY iNCOmPRESSiBLE FLUiDS OF VON miSES TYPE

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Acta mathematica Scientia 2019年第1期39卷 1-10页

作者： martin FUCHS Jan müLLER Fachbereich 6.1 mathematik Universit?t des Saarlandes

We consider entire solutions u of the equations describing the stationary flow of a generalized Newtonian fluid in 2 D concentrating on the question, if a Liouville-type result holds in the sense that the boundedness of u implies its constancy. A positive answer is true for p-fluids in the case p > 1(including the classical Navier-Stokes system for the choice p = 2), and recently we established this Liouville property for the Prandtl-Eyring fluid model,for which the dissipative potential has nearly linear growth. Here we finally discuss the case of perfectly plastic fluids whose flow is governed by a von mises-type stress-strain relation formally corresponding to the case p = 1. it turns out that, for dissipative potentials of linear growth, the condition of μ-ellipticity with exponent μ is sufficient for proving the Liouville theorem.

关键词： generalized Newtonian fluids perfectly plastic fluids von mises flow Liouville theorem

Prediction of Soil Depth from Digital Terrain Data by integrating Statistical and Visual Approaches

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Pedosphere 2010年第3期20卷 361-367页

作者： F. m. ZiADAT international Center for Agricultural Research in the Dry Areas (iCARDA) P.O. Box 5466Aleppo (Syria)

information about the spatial distribution of soil attributes is indispensable for many land resource management applications; however, the ability of soil maps to supply such information for modern modeling tools is questionable. The objectives of this study were to investigate the possibility of predicting soil depth using some terrain attributes derived from digital elevation models （DEms） with geographic information systems （GiS） and to suggest an approach to predict other soil attributes. Soil depth was determined at 652 field observations over the A1-muwaqqar Watershed （70 km2） in Jordan. Terrain attributes derived from 30-m resolution DEms were utilized to predict soil depth. The results indicated that the use of multiple linear regression models within small watershed subdivisions enabled the prediction of soil depth with a difference of 50 cm for 77% of the field observations. The spatial distribution of the predicted soil depth was visually coincided and had good correlations with the spatial distribution of the classes amalgamating three terrain attributes, slope steepness, slope shape, and compound topographic index. These suggested that the modeling of soil-landscape relationships within small watershed subdivisions using the three terrain attributes was a promising approach to predict other soil attributes.

关键词： compound topographic index digital elevation model GiS watershed

Jet flows from bubbles during subcooled pool boiling on micro wires

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Science China(Technological Sciences) 2005年第4期48卷 385-402页

作者： D. m. Christopher Laboratory of Phase Change and interfacial Transport Phenomena Department of Thermal Engineering Tsinghua University Beijing 100084 China

An experimental investigation was conducted on subcooled nucleate boiling on ultra-small wires having diameters of 25―100 μm. High-speed photography and laser PiV (Particle image Velocimetry) technology were used to visually observe the bubble dynamics. For highly subcooled boiling at moderate heat fluxes, the bubbles generally remained attached to the micro heating wires and bubble-top jet flows were clearly observed. Smaller bubbles usually had stronger bubble-top jet flows, while larger bubbles seemed to produce multi-jet flows. The structures of the bubble-top jet flows, as well as multi-jet flows, were proposed from the experimental observation. A model was developed to describe jet flow phenomena from bubbles on micro wires. Numerical simulations for bubbles having diameter of 0.03 and 0.06 mm showed that both the bubble-top and multi-jet flows were induced by a strong marangoni effect due to high temperature gradients near the wire. The predicted velocity magnitudes and flow structures agreed very well with experimental measurements. The bubble size relative to the wire is an important factor affecting the jet flow structure. For a 0.03 mm bubble on a 0.1 mm wire, only a bubble-top jet flow forms, while a complex multi-jet flow pattern forms around the bubble with a weak bubble-top jet and two side jet flows for a 0.06 mm bubble.

关键词： subcooled boiling, bubble, multi-jet, jet flow, PiV, marangoni, CFD.

movement analysis in the diagnosis and management of Parkinson’s disease

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Neural Regeneration Research 2025年第2期20卷 485-486页

作者： Johannes Burtscher nicolas Bourdillon Jules mJanssen Daalen Aurélien Patoz Julien FBally martin Kopp Davide malatesta Bastiaan RBloem institute of Sport Sciences University of LausanneLausanneSwitzerland Radboud University medical Center Department of NeurologyDonders Institute for BrainCognition and BehaviorCenter of Expertise for Parkinson and Movement DisordersNijmegenThe Netherlands Radboud University medical Center Department of Medical BioSciencesNijmegenThe Netherlands Research and Development Department Volodalen Swiss Sport LabAigleSwitzerland Service of Neurology Department of Clinical NeurosciencesLausanne University Hospital(CHUV)and University of Lausanne(UNIL)LausanneSwitzerland Department of Sport Science University of InnsbruckInnsbruckAustria

Challenges in the diagnosis and treatment of Parkinson’s disease:Parkinson’s disease(PD)is an increasingly prevalent neurodegenerative disease,at first sight primarily characterized by motor symptoms,although non-motor symptoms also constitute a major part of the overall ***,this disease cannot be diagnosed reliably until a large part of the vulnerable dopaminergic neurons has been irretrievably lost,and the disease progresses *** biological criteria for PD have been proposed recently and might eventually improve early diagnosis,but they require further validation,and their use will initially be restricted to a research environment(Darweesh et al.,2024).

关键词： diagnosis Clinical eventually

The synergetic effects of two CCAAT boxes in Aspergillus niger glaA gene promoter on activation of PglaA transcription

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Science China(Life Sciences) 2004年第2期47卷 139-147页

作者： WANG H. m. Genencor international Inc. 925 Page Mill Road Palo Alto California 94304 USA

EmSA and footprinting analyses have revealed that the -489—-414 bp and the -390—-345 bp (designated DC and PC respectively) upstream of the Aspergillus niger T21 glaA gene were bound by one protein factor in the A. niger T21 whole cell extract. Both DC and PC contained CCAAT pentanucleotides. The functions of DC and PC in regulation of expression of glucoamylase (GLA) were studied. CCAAT pentanucleotides were replaced with CGTAA and the mutated DNA fragments DCm and PCm lost the binding activities of protein factors in vitro. in vivo when either DC or PC was mutated or the relative orientations between them were changed on the PglaA, the transcriptional activity of PglaA decreased to a basal level. introduction of multi-copies of DC into the original site at the PglaA in A. niger T21 decreased the expression of endogenous GLA expression and the exogenous reporter E. coli uidA gene introduced under the PglaA promoter, while having no effect on the uidA gene under the control of PgpdA. EmSA re-vealed that the levels of the specific DNA-binding protein factors in the transformants maintained the same meaning that introduction of multi-copies of DC caused the titration effect. AnghapC gene was cloned from A. niger T21 cDNA and introduced into the DC multi-copied strains. The expression of AnghapC improved the expression of the endogenous GLA and the exogenous gene controlled by PglaA. These results showed that both the CCAAT pentanucleotides were necessary for DC and PC binding to the protein factors, and the simultaneous binding of DC and PC to the protein was necessary for promoting the transcriptional activity of PglaA. AngHapC was the specific positive trans-acting protein factor binding to DC.

关键词： Aspergillus niger glucoamylase, synergetic effect, mutation analysis, multi-copy of CCAAT box, titration effect.

A simple method of tuning series cascade controllers for unstable systems

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控制理论与应用（英文版） 2013年第4期11卷 661-667页

作者： Simi SANTOSH m.CHiDAmBARAm Department of Chemical Engineering Indian Institute of Technology Madras

A simple method is proposed to design P/Pi controllers for a series cascade control system for unstable first order plus time-delay （FOPTD） systems. in this paper, the controller design for unstable FOPTD systems cascaded in series with stable/unstable FOPTD systems is considered. The proposed method is based on equating the coefficients of corresponding powers of s and s2 in the numerator to α1 and α2 times those of the denominator of the closed-loop transfer function for a servo problem. The open loop system consists of an unstable FOPTD system cascaded in series with a stable/unstable FOPTD system. Only two tuning parameters （α1 and α2） are required for the design of controllers. The closed-loop performances are evaluated for both the servo and regulatory problems and the performances are found to be better than that of the well established synthesis method. The robustness for uncertainty in the model parameters is studied and compared with that of the controllers designed by the synthesis method.

关键词： Cascade control Time-delay process Pi controller P controller FOPTD model Tuning

mineralogical and Geochemical Assessment of Clay Properties of Edda, Afikpo Sub Basin Nigeria for Possible Use in the Ceramics industry

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Journal of Geological Research 2021年第2期3卷 41-52页

作者： J.C.ike H.N.Ezeh m.O.Eyankware A.i.Haruna Department of Energy and Petroleum Studies Novena UniversityOgume Delta StateNigeria Department of Geology Ebonyi State UniversityAbakaliki Ebonyi State.Nigeria Geo-moses Consultancy Limited.Warri Delta StateNigeria Department of Applied Geology Abubakar Tafawa Balewa UniversityBauchiNigeria

Clay samples from selected part of Edda were analyzed to identify the clay mineral types present,their chemical and physical properties with a view to appraising their industrial suitability as ceramic *** mineralogical and geochemical analyses were done using the principles of X-Ray diffraction and X-ray fluorescence respectively.A total of seven clay samples were used for the study,other tests such as plasticity,bulk density,shrinkage,loss on ignition(LOi)and water absorption capacity was carried out to determine the amount of water absorbed under specified *** basic industrial properties assessment showed that more than 70%of the clays are *** clays exhibited low to moderate plasticity,moderate shrinkage and bulk density,low to moderate values of both loss on ignition and water absorption *** clays are buff to yellowish in *** results of x-ray fluorescence revealed that the mean concentration of major oxide in the clays is shown as follows:SiO_(2)(62.78%),Al_(2)O_(3)(20.25%),total Fe(6.09%),CaO(0.56%),mgO(3.21%),Na_(2)O(0.47%),K_(2)O,(1.44%)and TiO_(2)(0.52%).The samples have high silica content,low alumina and low oxide *** results of x-ray diffraction revealed that kaolinite is the dominant clay mineral with illite and montmorillonite occurring in subordinate amounts,while quartz and feldspar are the non-clay components *** characteristics of the clays for each parameter were compared with industrial *** properties are appropriate for the Afikpo clays to be useful in the manufacturing of ***,since the silica content of the clays is high further beneficiation is recommended.

关键词： X-ray mineral Liquid limit Plastic limit industrial standard Atterberg limit

Removal of Technetium (<sup>99</sup>Tc) from Aqueous Waste by manganese Oxide Nanoparticles Loaded into Activated Carbon

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Journal of Analytical Sciences, methods and instrumentation 2020年第1期10卷 12-35页

作者： W. m. Abdellah H. i. El-Ahwany R. El-Sheikh Radiation Protection Department Egypt Nuclear and Radiological Regulatory Authority Cairo Egypt Chemistry Department Faculty of Science Zagazig University Zagazig Egypt

Technetium-99 is a radioactive isotope with a half-life of 2.13 × 105 year. 99Tc is a significant contaminant of concern to the world. For this reason, a detailed understanding of technetium chemistry is essential for the protecting the public and the environment especially after increasing the various applications and uses of isotopes in the medical practices. Therefore, treatment of waste increases prior to the safe discharge to the environment or the storage. The sorption of technetium in the form of pertechnetate on a nano manganese oxide loaded into activated carbon has been investigated. Nano manganese oxide (NmO) was synthesized from manganese chloride and potassium permanganate by co-precipitation and forming a new composite by loading a nanoparticle into a modified activated carbon by different ratios. modifications of activated carbons using different concentrations of HNO3 (4 m, 6 m and 8 m) are used in prepared composites. Fourier transform infrared spectroscopy (FT-iR), X-Ray Diffraction (XRD) and Scanning Electron microscope (SEm) were used to characterize the prepared composites. The adsorption of anions from low level radioactive aqueous waste was examined using batch technique. Different parameters affecting on the adsorption process were studied for the removal of . The results revealed that NmO/AC (4 m, 6 m and 8 m) has a high adsorption efficiency (93.57%, 90.3% and 90.3%) respectively compared to NmO and AC which have a lower adsorption efficiency (41% and 38.9%) respectively. moreover, the adsorption isotherm belonged to Freundlich model, the adsorption data followed pseudo-second order model and the thermodynamic study indicated that the adsorption of on Nano-composites was an exothermic and spontaneous process.

关键词： Nano manganese Oxide (NmO) Activated Carbon (AC) Technetium-99 Co-Precipitation Adsorption