Design, Fabrication and Characterization of a Piezoelectric Microgenerator Including a Power Management Circuit

We report in this paper the design, fabrication and experimental characterization of a piezoelectric MEMS microgenerator. This device scavenges the energy of ambient mechanical vibrations characterized by frequencies in the range of 1 kHz. This component is made with Aluminum Nitride thin film deposited with a CMOS compatible process. Moreover we analyze two possible solutions for the signal rectification: a discrete doubler-rectifier and a full custom power management circuit. The ASIC developed for this application takes advantage of diodes with very low threshold voltage and therefore allows the conversion of extremely low input voltages corresponding to very weak input accelerations. The volume of the proposed generator is inferior to 1mm3 and the generated powers are in the range of 1$\mu$W. This system is intended to supply power to autonomous wireless sensor nodes.Comment: Submitted on behalf of EDA Publishing Association (http://irevues.inist.fr/EDA-Publishing

Method of computation of energies in the fractional quantum Hall effect regime

In a previous work, we reported exact results of energies of the ground state in the fractional quantum Hall effect (FQHE) regime for systems with up to $N_{\text{e}} = 6$ electrons at the filling factor $\nu = 1/3$ by using the method of complex polar coordinates. In this work, we display interesting computational details of the previous calculation and extend the calculation to $N_{\text{e}} = 7$ electrons at $\nu = 1/3$. Moreover, similar exact results are derived at the filling $\nu = 1/5$ for systems with up to $N_{\text{e}} = 6$ electrons. The results that we obtained by analytical calculation are in good agreement with their analogues ones derived by the method of Monte Carlo in a precedent work.Comment: 9 pages, 1 figur

THE EFFICIENCY EXTENT OF THE INTERNAL CONTROL ENVIRONMENT IN THE PALESTINIAN HIGHER EDUCATIONAL INSTITUTIONS IN GAZA STRIP

The purpose of this research is to identify the extent of the efficiency of the internal control environment in the Palestinian higher educational institutions in Gaza Strip from the perspective of employees in the Palestinian universities in Gaza Strip, where researchers used in the study five universities. The researchers adopted in their study the descriptive and analytical approach. The research community consists of administrative employees and academic employees with administrative duties. Senior management or the University Council was excluded. The study population compromises of (392) employees. A stratified random sample was chosen and (197) questionnaires were distributed. (160) questionnaires were received back with a return rate of (81.2%).The researchers used a questionnaire to collect that which then was analyzed using (SPSS) to get the results. The research found the following results: the absence of a fundamental difference between the responses of males and females. The lack of significant difference between the responses of the respondents attributed to the variable age. The lack of significant difference between the responses of the respondents attributed to the variable of years of service. And the existence of a fundamental difference between the responses of the respondents attributed to the university variable. The existence of a fundamental difference between the responses of the respondents attributed to the Qualification variable. The existence of a fundamental difference between the responses of the respondents attributed to the administrative level variable. The research found a group of recommendations including: the need to raise awareness of censorship as the basis for the protection of employees in all administrative levels from making mistake.Updating the systems and instructions of control periodically and parallel with the scientific progress and technology.Benefit from regional and international experiences in the application of internal control standards which commensurate with the administrative system of the institution

Action des Nématodes Entomopathogènes du genre Heterorhabditis sur les oeufs de criquet, Locusta migratoria (L.) (Orthoptera : acrididae)

Les nématodes entomopathogènes (EPN) ont été décelés pour la première fois sur les oeufs de criquets. Quelques populations d’Heterorhabditis isolées sur les oeufs de Schistocera gregaria Forsskål, de Locusta migratoria L. (Orthoptera : Acrididae) et sur les chenilles de Galleria mellonella L. (Lepidoptera : Pyralidae) ont été isolées. La pathogénie des populations du nématode isolées sur les oeufs est plus importante que celle sur les chenilles. A l’inverse la pathogénie des EPN isolée sur les chenilles est plus importante sur les chenilles de l’insecte modèle. Les potentialités biochimiques des nématodes entomopathogènes et de leurs bactéries symbiontes en rapport avec l’activité protéolytique et chitinase ont été étudiées. Les bactéries mutualistes des nématodes isolées sur les oeufs de criquet montrent une importante activité protéolytique.Mots Clés: Heterorhabditis, nématode entomopathogène, oeuf, criquet, Locusta migratoriaEnglish Title:  Effect of entomopathogenic nematode, heterorhabditis on eggs, Locusta migratoria (L.)English AbstractEffect of entomopathogenic nematode, Heterorhabditis on eggs locust, Locusta migratoria (L.) First report of entomopathogenic nematodes have been detected in locusts eggs. Some Heterorhabditis populations isolated on eggs of Schistocera gregaria Forsskål, of Locusta migratoria L. (Orthoptera : Acrididae) and caterpillars of Galleria mellonella L. (Lepidoptera : Pyralidae) were isolated. Nematode populations isolated from insect eggs aremore aggressive on locust eggs than those obtained by greater wax moth traps. Pathogenesis on nematodes isolated on carterpillar larvae bait, is greater on Galleria mellonella, insect model of EPN, than those bait by locust eggs. Biochemical potential of EPN and their symbiotic bacteria is related on proteolytic and kinetics activity. Mutualistic bacteria of nematode isolated on locust eggs show a significant proteolytic activity.Keywords: Heterorhabditis, entomopathogenetic nematode, Egg, locust, Locusta migratori

Experimental Study of Pathological and Some Immunological Aspect of Infection Pseudomonas aeruginosa bacteria and Exotoxin in Rabbits

Pseudomonas aeruginosa is an opportunistic pathogen which infect immunocompromised patients. bacteria produce large types of virulence factors that serves its pathogenicity. The exotoxin A is major toxic extracellular virulent factor produced by P. aeruginosa. To clear the effect of exotoxin A and P. aeruginosa , Bacteria suspension and Exotoxin A extraction were injected intraperitonially in four group of rabbits, the result show there was significant decrease in total leukocyte count in all groups specially after 7 days from injection of Bacteria suspension and Exotoxin A also there is increase in neutrophilia percentage is the same period, the bacteria suspension and toxin A are capable alone or in both to activated phagocytosis, and produce neutralizing antibodies and produce pathological and immunological effect in liver spleen , kidney and lung and this suggest that toxin A and P. aeruginosa bacteria can effect in some immunological and pathological aspect when injected in experimental rabbit

PrekotAC as a new filter aids material for fabric filter in air filtration system

Fabric filter has a short life span due to wear and tear influenced by the operating conditions of the system. Treatment of fabric filter using pre-coating material is one of the simplest technique to overcome this problem where it works as a filtration aids that will coat a layer of inert material onto the surface of the fabric. Pre-coating acts as a barrier to block and remove undesired particles from gas stream but allowing a uniform air flow passing through the filter media. The morphology of dust cake that accumulated on the surface of the filter media depends on several properties of the particles such as shape and size. Hence, study presents the characterization of a newly formulated filtration aids known as PrekotAC consisting of a different combination of pre-coating material PreKot™ and activated carbon. The aim is to determine the best combination of PrekotAC admixtures as a filtration aids suitable for a fabric filtration system. Various characteristics of the formulated admixtures such as its particle size distribution, bulk density, moisture content as well as its morphology were investigated and presented in this paper

Measurement of the total cross section for e^+e^-→hadrons at √s=10.52 GeV

Using the CLEO detector at the Cornell Electron Storage Ring, we have made a measurement of R≡σ(e^+e^-→hadrons)/σ(e^+e^-→μ^+μ^-)=3.56±0.01±0.07 at √s=10.52 GeV. This implies a value for the strong coupling constant of α_s(10.52 GeV)=0.20±0.01±0.06, or α_s(MZ)=0.13±0.005±0.03

Characteristics and adsorption performance of formulated trikotaC filter aids

TrikotAC filter aids is a combination of a pre-coating material PreKot™ with two adsorbents; activated carbon and lime and their characteristics were investigated in this study. TrikotAC was formulated into three different weight ratios of 5:1:94, 10:1:89 and 10:5:85, respectively. The relationship between adsorption properties and characteristics of the formulated materials particle size distribution, particle density, bulk density, and BET surface area were investigated. The results showed that the adsorption capacity for TrikotAC 10:5:85 (11.88 mg/g) was higher than for the other formulated filter aids samples, and the formulated filter aids material TrikotAC showed promising characteristic as a filter aids and adsorbent for organic compound in fabric filtration system

The Effect of Irrigation Frequency and Farm Yard Manure on Salt Leaching Under Saline – Sodic Soil

Abstract: Northern state, Sudan is extremely affected by desertification and Salinization processes, there for this study aimed to investigate an effective method to improve the salt affected soil. Two field experiments were carried out in two successive seasons ( July 2005 – June 2006 ) at Dongola University farm, in the North State to investigate the effect of irrigation frequency ( 7 and 14 days ) and farm yard manure (M0 , M1 , M2 , andM3 ) on salt leaching undersaline – sodic soil . The experiment was designed in spilt – plot design , where irrigation frequency was assigned in the main plots ( 6x28m) and farm yard manure were the sub – plots ( 6x7m) .The total cultivated area was 1342m2 for each experiment. The quantity of water applied was estimated according to Jensen andHaise (1963 ) . The total water quantity was the same by the end of the season. In general , the result indicated that irrigation frequency of 7 days enhanced salt leaching from the root zone. Generally , the reduction in electrical conductivity ( ECe ) and sodium adsorption ratio ( SAR ) due to irrigation frequency was more effective in 7 day irrigation interval as compared with 14 – day irrigation interval . the data obtained indicated that the addition of FYM 10 ton/feddan, significantly degreased the (ECe) and the (SAR) and leached them below the root zone. So, we can conclude that the efficiency of salt leaching is markedly affected by irrigation frequency and yard manure