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In this paper, porous silicon has been prepared and studied by photochemical etching method using a n-type silicon wafer with electrical resistivity (0.01-0.02 Ω.cm), orientation (100), hydrofluoric acid of 20% HF, current density of 15 mA / cm2 and etching time at (5 min). Silver nanoparticles (AgNPs) have been deposited using laser ablation by drop casting with different laser energy of 400,600 and 800m J. The electrical properties (I-V measurements) of silver nanoparticles on porous silicon have studied in both light and dark conditions. It can be seen the samples behave a rectifier and the current density increases with increase laser energy due to increase in concentration of silver nanoparticles, which lead to a decrease in the values of resistivity as the laser energy increases, this is attributed to the pores are filled with silver nanoparticles and lead to interference between silver and the porous silicon layer. The silver nanoparticles play an important role in forming a homogeneous layer and enhancing the crystal stability of the porous silicon layer.

A simple , rapid and sensitive spectrophotometric method for the determination of aliphatic amines was developed .The method is based on the proton transfer reaction using 3,5- dinitrosalicylic acid (DNS) reagent in basic medium forming colored products with maximum absorption at 415 nm .The molar absorptivity ranged from 5100 l. mol-1 .cm-1 for tributylamine to 12000 l. mol-1.cm-1 for dibutylamine .The method is obeyed Beer’s law over the concentration range (0.12-12) µg.ml-1.The accuracy ( average recovery ) is 99.73% and the precision (RSD) is less than 4.50% .This method is applied successfully for the assay of ethanolamine and ethylenediamine in their pharmaceutical preparations .

This study has include the exposure of the seeds, explants and callus of Helianthus annus L. by gamma rays, with the doses (0.3, 0.7, 1.1, 1.3, 1.5) kilorad, this resulted increasing protein content in radiant peeled seeds with all radiant doses, and in radiant complete seeds, only four radiant doses (0.3, 1.1, 1.3, 1.5) kilorad, also the leaves and stems callus that produced from radiant seed plants , also in all radiant callus. At dose ( 1.3) kilorad initiative seeds has recorded best percents of oil in both leaves and hypocotyls that produced it, also shown that highestpresent of oil in both radiant hypocotyls and leaves callus. Oil percent in callus produced by radiant explants was in som~ dose higher than the control or equal .

Peroxidase enzyme was extracted from callus of different explants and immature embryos of Phaseolus vulgaris L. .The maximum activity of enzyme showed in the embryos callus sample.The higher activity of enzyme was in the ( 4months) age of callus for each of leaves ,roots and embryos and in (6months) for cotyledons callus,the stems callus recorded best activity in (2months)old.Using of ammonium sulphate precipitation result in high enzyme activity in all samples.When the exchange chromatochraphy was used to purifiy stems callus extract,(5)proteinapexes observed and ( 4 )of it was active .In the separation of proteins by using the electrofousing techniques, the samples of embryos ,leaves,stems,cotyledons and roots were separated at pH range (5.13- 6.14 ).The minimum activity of enzyme observed at ( 4day) age for all explants samples,but the maximum activity was in the roots samples at (14day)age

Twelve isolates of Pseudomonas aeruginosa, Klebsiella pneumoniae and Proteus mirabilis were tested against chlorhexidine and sodium hypochlorite. Bacterial suspension was added to different concentrations of disinfectant, after (5,15,30,45) minutes samples were taken and cultured on nutrient agar, the effect of disinfectants were recorded at the time periods tested. The study showed that chlorhexidine is more active than sodium hypochlorite, where concentrations of (3 %, 2 %, 1.5%) of chlorhexidine showed an absolute activity (100%) on all isolates after (5) minutes of treatment, while only (3%) concentration of sodium hypochlorite showed that activity during the same time. The study found that the effect of disinfectant increases with the increase of concentration and treatment time. The study also indicated that Ps.aeruginosa isolates were more resistant to disinfectant in comparison with the other two species, while Pr.mirabilis isolates were more sensitive to them. الملخصاختبرت حساسیة (12) عـزلة من جراثیم Klebsiella pneumoniae , Pseudomonas aeruginosa Proteus mirabilis, لمطهریّ الکلورهکسدین وهایبوکلورات الصودیوم .أجری الاختبار من خلال إضافة المعلق الجرثومی إلى تراکیز مختلفة من المطهر، وبعد مرور (45, 30 , 15 , 5 ) دقیقة , أخذت عینات من مزیج المعاملة وزرعت على وسط الأکار المغذی ، سجل تأثیر المطهرات فی المدد الزمنیة المدروسة . تبین من الدراسة أن مطهر الکلورهکسدین أکثر فعالیة من مطهر هایبوکلورات الصودیوم إذ أعطت التراکیز (%1.5 , %2 , %3 ) من مطهر الکلورهکسدین فعالیة مطلقة (%100) على العزلات جمیعاً خلال مدة (5) دقائق من المعاملة ، فی حین کان للترکیز (%3) حسب من مطهر هایبوکلورات الصودیوم نفس الفعالیة على العزلات جمیعاً خلال المدة الزمنیة نفسها . ووجدت الدراسة أن تأثیر المطهر یزداد بازدیاد الترکیز والمدة الزمنیة للمعاملة . کما تبین أن جرثومةPs.aeruginosa أکثر مقاومةً للمطهرات مقارنةً بالنوعین الآخرین ، فی حین کانت جرثومة Pr.mirabilis أکثر حساسیةً لها .

This research is concerned with the preparation of four aliphatic or aromatic oximes, prepared from benzil and heterocyclic aldehydes and the determination of their pKa by potentiometric method. It is proved in this study that oximes under investigation have hydrogen bonds, as identified earlier by different physical method. A comparison ofpKa between these oximes are performed at constant temperature and solvent composition. The potentiornetric method was founded to be fast, simple and precise with accLlracy in the rang +0.001 pKa unit.The study comes to conclusion that the type of isomer (alpha or beta) in oximes, have a noticeable influence on pKa value of isomer.

This study carried out the induction of callus from different explants (leaves, stems and roots) of the medicinal plant Pi/npinc/la anisum by using MS medium which c.'miained different concentration;-; of Benzyl adenin BA and Naphthaline acetic acid NAA, The results showed that MS medium with 2.0 mg/1 BA and 1.0 mg/1 NAA was trie best medium for the induction and growth of callus. Regeneration of plants from the callus was obtained, specially from callus of leaves which gave the higher percentage, then followed by the callus of steins an ' roof' Al:;o, the results showed the one stop i -generation for all the ca '. " 'r- •': MS medium which contained 1.0 in.;,/'; for each ^ BA and 1 "T bjst medium for rooting was MS with i ,0 mg/1 NAA.