Tetraphenolate niobium and tantalum complexes for the ring opening polymerization of ε-caprolactone

Reaction of the pro-ligand α,α,α′,α′-tetra(3,5-di-tert-butyl-2-hydroxyphenyl-p-)xylene-para-tetraphenol (p-L¹H₄) with two equivalents of [NbCl₅] in refluxing toluene afforded, after work-up, the complex {[NbCl₃(NCMe)]₂(μ-p-L¹)}·6MeCN (1·6MeCN). When the reaction was conducted in the presence of excess ethanol, the orange complex {[NbCl₂(OEt)(NCMe)]₂(μ-p-L¹)}·3½MeCN·0.614toluene (2·3½MeCN·0.614toluene) was formed. A similar reaction using [TaCl₅] afforded the yellow complex {[TaCl₂(OEt)(NCMe)]₂(μ-p-L¹)}·5MeCN (3·5MeCN). In the case of the meta pro-ligand, namely α,α,α′,α′tetra(3,5-di-tert-butyl-2-hydroxyphenyl-m-)xylene-meta-tetraphenol (m-L²H₄) only the use of [Nb(O)Cl₃(NCMe)₂] led to the isolation of crystalline material, namely the orange bis-chelate complex {[Nb(NCMe)Cl(m-L²H₂)₂]}·3½MeCN (4·3½MeCN) or {[Nb(NCMe)Cl(m-L²H₂)₂]}·5MeCN (4·5MeCN). The molecular structures of 1–4 and the tetraphenols L¹H₄ and m-L²H₄·2MeCN have been determined. Complexes 1–4 have been screened as pre-catalysts for the ring opening polymerization of ε-caprolactone, both with and without benzyl alcohol or solvent present, and at various temperatures; conversion rates were mostly excellent (>96%) with good control either at >100 °C over 20 h (in toluene) or 1 h (neat)

Simulation of Flow Pattern through a Three-Bucket Savonius Wind Turbine by Using a Sliding Mesh Technique

Vertical axis wind turbine (VAWT) type Savonius rotor is self-starting, inexpensive, less technicality & high productivity wind machine, which can accept wind from any direction without orientation, and provides high starting torque. The investigations of aerodynamic parameters and the flow pattern of the turbulent flow through the rotor have high aspect on Savonius wind turbine performance. The flow pattern through a three buckets Savonius rotor model of 10cm diameter inside smoke wind tunnel with high-speed camera was investigated experimentally. The commercial code FLUENT 6.3.26 used to simulate the turbulent flow (M<0.3,Re>2000) by RNG K-e turbulent model. Two-dimensional model carried out the simulation of the flow pattern, velocities and pressures of airflow within a Savonius wind rotor placed in Smoke wind tunnel. The domain of the airflow dived for two zone, first zone up and down stream flow meshed by fixed structured grid generation. The second zone is around Savonius rotor; the flow pattern created by a pitched blade rotor was calculated by using a sliding mesh technique with unstructured grid generation. Three time steps between two blades of rotor is taken, which give three angular orientations of blades. The CFD results show good agree with experimental results of flow pattern. It is concluded that the sliding mesh method is suitable for the prediction of flow patterns around wind turbine. Then after ensured from the reliability of CFD simulation, it can be used for studying the velocity contour and the pressure distribution around the turbine

Molecular Study for Diagnosis of Ureaplasma parvum in Women with Recurrent Miscarriage

The objects of study is concerted to investigate the occurrence of Ureaplasma parvum in women with recurrent abortion and to determine the distribution of U. parvum serovars (1, 3, 6, 14) in women with recurrent abortion by conventional polymerase chain reaction (PCR) technique. In total, 130 samples included vaginal bleeding, vaginal swab, and urine, were collected from women with recurrent abortion and 40 samples included vaginal swab and urine from control women without recurrent abortion. Through the study, two types of media were used, Ureaplasma broth (IH Broth) and Ureaplasma agar (IH Agar). The positive isolates for Ureaplasma spp. were investigated by conventional PCR technique for identification of U. parvum and subtyping to their serovars (1, 3, 6, 14). The results revealed the U. parvum was identified in 29.6% from patient group and 11% from the control group. U. parvum isolates were further subtyped by using PCR, the results showed the serovar 3 was the most frequent isolate in proportion (42.8%), whereas serovar 1 (28.5%), serovar 6 (14.2%), and serovar 14 (14.2%) in patient group but in the control group only serovar 1 was isolated in rate (11%). These results evidently indicate that U. parvum may be an important etiologic agent for recurrent abortion

New pre-catalysts for ring opening of lactides/lactones based on earth abundant metals

In this study, a number of Nb, Ta, Mo, V, Al, Li and Zn complexes have been synthesised and fully characterised. The catalytic behavior of these pre-catalysts towards the ring opening polymerization (ROP) of the cyclic esters is discussed.Chapter 1 Presents an introduction to the history of polymers (from polyethylene to biodegradable polymers from cyclic esters), early discovery, mechanism of ring opening polymerisation and the use of vanadium, niobium, tantalum and molybdenum, aluiminium, lithium and zinc complexes as polymerization catalysts.Chpter 2 This chapter discussed results when the pre-ligands α,α,α’,α’-tetra(3,5-di-tert-butyl-2-hydroxyphenyl-p-)xylene-para-tetraphenol(p-L¹H₄) and α,α,α’,α’tetra (3,5-di-tert-butyl-2-hydroxyphenyl-m-)xylene-meta-tetraphenol (m-L²H₄) are reacted with a number of niobium and tantalum precursors such as [NbCl₅], [TaCl₅] or [Nb(O)Cl₃(NCMe)₂]. The resulting products {[NbCl₃(NCMe)]₂(μ-p-L¹)}·6MeCN (1·6MeCN), {[NbCl₂(OEt)(NCMe)]₂(μ-p-L¹)}·3½MeCN·0.614 toluene (2·3½MeCN·0.614 toluene), {[TaCl₂(OEt)(NCMe)]₂(μ-p-L¹)}.5MeCN (3·5MeCN), {[Nb(NCMe)Cl(m-L²H₂)₂]}·3½MeCN(4·3½MeCN) and {[Nb(NCMe)Cl(m-L²H₂)₂]}·5MeCN (4·5MeCN) were structurally characterized. Complexes 1–4 were screened as pre-catalysts for the ROP of ε-caprolactone, both with and without benzyl alcohol or solvent present, and at various temperatures.Chapter 3 In this chapter, the reaction of the bulky bi-phenols 2,2′-RCH[4,6-(t-Bu)₂C₆H₂OH]₂ (R = Me L³MeH₂, Ph L⁴PhH₂) with the bis(imido) molybdenum(VI) tert-butoxides [Mo(NR¹)(NR²)(Ot-Bu)₂] (R¹ = R² = 2,6-C₆H₃-i-Pr2; R¹ = t-Bu, R² = C₆F₅) has been studied. The complexes [Mo(NC₆H₃i-Pr₂-2,6)2L3Me] (5), [Mo(NC₆H₃i-Pr₂-2,6)2L⁴Ph] (6) and [Mo(Nt-Bu)(μ-NC₆F₅)(L³Me)]₂ (7) were isolated. Similar use of the tri-phenol 2,6-bis(3,5-di-tert-butyl-2-hydroxybenzyl)-4-methylphenol (L⁵H₃) with [Mo(NC₆H₃i-Pr₂-2,6)₂(Ot-Bu)₂] afforded the oxo-bridged product [Mo(NC6H₃i-Pr₂-2,6)(NCMe)(μ-O)L5H]₂ (8), whilst use of the tetra-phenols L¹pH₄/L²mH₄ led to {[Mo(NC₆H₃i-Pr₂-2,6)₂]₂(μ-L¹p)} (9) or {[Mo(NC₆H₃i-Pr₂-2,6)₂]₂(μ-L²m)}(10), respectively. Similar use of [Mo(NC₆F5)2(Ot-Bu)₂] with L¹pH₄ afforded {[Mo(NC₆F₅)(Ot-Bu)₂]₂(μ-L¹p)}·6MeCN (11·6MeCN). The molecular structures of 5, 6·CH₂Cl₂, 7, 8·6MeCN, 10·2C₆H14, and 11·6MeCN are reported. These complexes have been screened for their ability to act as catalysts for the ROP of ε-caprolactone; for comparative studies the complex [Mo(NC₆H₃i-Pr₂ 2,6)₂Cl₂(DME) (12) has also been screened.Chpter 4 This chapter focuses on the use of the vanadyl complexes. The new complexes [VO(Ot-Bu)L³] (13), {[VO(Oi-Pr)]₂(µ-p-L¹p)} (14) {[VO(OR)]₂(µ-p-L²m)} (R = i-Pr 15, t-Bu 16 have been prepared from [VO(OR)₃] (R = n-Pr, i-Pr or t-Bu) and the respective phenol, namely 2,2/-ethylidenebis(4,6-di-tert-butylphenol) (L³H₂) or Lp/mH4. For comparative studies, the known complexes [VO(µ-On-Pr)L³]₂ (18), [VOL⁶]₂ (19) (L6H₃ 2,6-bis(3,5-di-tert-butyl-2-hydroxybenzyl)-4-tert-butylphenol) were prepared. An imido complex {[VCl(Np-tolyl)(NCMe)]₂(μ-p-L¹p)} (17) has also been prepared. The molecular structures of complexes 13 – 19 are reported, and these complexes 13 – 19 have been screened for their ability to ring open polymerise ε-caprolactone, L-lactide or rac-lactide with and without solvent present. The co-polymerization of ε-caprolactone with L-lactide or rac-lactide was also studied.Chapter 5 describes the reaction of R¹R²CHN=CH(3,5-t-Bu₂C₆H₂-OH-2) (R¹ = R² = Me L⁷H; R¹ = Me, R² = Ph L⁸H; R¹ = R² = Ph L⁹H) with slightly greater than one equivalent of R³₃Al (R³ = Me, Et), which afforded the complexes [(L⁷⁻⁹)AlR³₂] (L⁷, R³ = Me 20, R³ = Et 21; L⁸, R³ = Me 22, R³ = Et 23; L³, R³ = Me 24, R³ = Et 25); complex 20 has been previously reported. Use of the N,O-ligand derived from 2,2/-diphenylglycine afforded either 24 or an amine by-product [Ph₂NCH₂(3,5-t-Bu₂C₆H₂-O-2)AlMe₂] (26). The known Schiff base complex [2-Ph₂PC₆H4CH₂(3,5-t-Bu₂C₆H₂-O-2)AlMe₂] (27) and the product of the reaction of 2-diphenylphosphinoaniline 1-NH₂,2-PPh₂C₆H₄ with Me₃Al, namely {Ph₂PC₆H₄N[(Me₂Al)₂µ-Me](µ-Me₂Al)} (28) were also isolated. For structural and catalytic comparisons, complexes resulting from interaction of Me₃Al with diphenylamine or benzhydrylamine, namely {Ph₂N[(Me₂Al)₂-Me]} (29) and [Ph₂CHNH(µ-Me₂Al)]₂·MeCN (30), were prepared. The molecular structures of the Schiff pro-ligands derived from Ph₂CHNH₂ and 2,2/-Ph₂C(CO₂H)(NH₂), together with complexes 24, 26 and 28 - 30·MeCN were determined. All complexes were screened for their ability to ROP ε-caprolactone, δ-valerolactone or rac-lactide, in the presence of benzyl alcohol, with or without solvent present.Chapter 6 describes the reaction of lithium alkoxides LiOR (R = t-Bu, Ph) with the acids 2,2/-Ph₂C(X)(CO₂H), where X = OH, NH₂, i.e. benzilic acid (2,2/-diphenylglycolic acid, benzH) or 2,2/-diphenylglycine (dpgH). In the case of benzH, reaction with one equivalent of LiOt-Bu in THF afforded the complex [Li(benz)(THF)]₂·2THF (31·2THF), which adopts a 1D chain structure. If acetonitrile is employed in the work-up under mild conditions, another solvate of 31 is isolated; use of LiOPh also lead to 31. Use of more robust work-up conditions afforded the complex [Li7(benz)7(MeCN)] (32·2MeCN·THF). Increasing the amount of LiOt-Bu (2 equivalents) led to the isolation of the complex {Li8(Ot-Bu)₂[(benz)](OCPh₂CO₂-CPh₂CO₂t-Bu)₂(THF)₄} (33). In the case of dpgH, use of two equivalents of LiOt-Bu in THF afforded [Li₆(Ot-Bu)₂(dpg)₂(THF)₂] (34), which contains an Li₂O₂ 6-step ladder. Similar reaction of lithium phenoxide with dpg afforded the complex [Li8(PhO)₄(dpg)₄(MeCN)₄] (35). The molecular structures of complexes 31 - 35 are reported; all were screened for their potential to act as pre-catalysts for ROP of ε-caprolactone (ε-CL), rac-lactide (r-LA) and δ-valerolactone (δ-VL).Chapter 7 describes the reaction of the dialkylzinc reagents R2Zn with the acids 2,2-Ph₂C(X)(CO₂H), where X = NH₂, OH, ie 2,2/-diphenylglycine (dpgH) or benzilic acid (benzH₂). With dpgH, the tetra-nuclear ring complexes [RZn(dpg)]₄, where R = Me (36), Et (37), 2-CF₃C₆H₄ (38), 2,4,6-F₃C₆H₂ (39) were isolated; complex 37 has been previously reported. The crystal structures of 36·2MeCN, 37 and 38·4(C7H8) ·1.59(H₂O) are reported, along with that of the intermediate compound (2-CF₃C₆H₄)₃B·MeCN and the known compound [ZnCl₂(NCMe)₂]. Complexes 36– 39, together with the known [(ZnEt)₃(ZnL)₃(benz)₃] (40; L = MeCN), have been screened, in the presence and absence of benzyl alcohol, for their potential to act as catalysts for the ROP of ε-caprolactone (ε-CL), δ-valerolactone (δ-VL) and rac-lactide (rac-LA); the co-polymerization of ε-CL with rac-LA was also studied.Chapter 8 This chapter presents the experimental section.Chapter 9 Appendix

Treatment with Dielectric Barrier Discharge (DBD) plasma restricts Aspergillus niger growth isolated from wheat grain

يؤثر التلوث الميكروبيولوجي بالفطر على جودة وسلامة تخزين حبوب القمح. تهدف هذه الدراسة إلى تقييم فاعلية البلازما الباردة في الحد من نمو فطريات الرشاشيات السوداء ( Aspergillus Niger )، وهو تلوث فطري معزول من حبوب القمح. أدى التفريغ  الكهربائي عبر حاجز عازل (DBD) الذي يعمل تحت الضغط الجوي إلى توليد البلازما الباردة المستخدمة في علاج فطريات الرشاشيات السوداء. تم التحقيق في تأثير بلازما DBD على فطريات الرشاشيات السوداء في فترات مختلفة (1 ، 2 ، 4 ، 6 ، و 15 دقيقة). أظهرت النتائج انخفاض معنوي كبير في نمو فطريات الرشاشيات السوداء ، و ايضا عدد الجراثيم مقارنة بالعينات غير المعاملة . أظهرت هذه الدراسة تقنية فعالة لتعزيز تخزين حبوب القمح ويمكن اعتبارها أساسًا لمزيد من الدراسات واسعة النطاق.Microbiological contamination by fungi impacts the quality and safety of wheat grain storage. This study aimed to evaluate the efficacy of cold plasma in restricting the growth of the fungus, Aspergillus niger, which was isolated from wheat grains. A dielectric barrier discharge (DBD) operating at atmospheric pressure generated cold plasma that was used to treat the fungus, and the impact of this treatment was investigated at various periods  1, 2, 4, 6, and 15 minutes. The results revealed a highly significant decrease in the growth and number of spores of Aspergillus niger compared to the controls. This study revealed an efficient technique for enhancing wheat grain storage that could be a foundation for further large-scale studies

Description and contrastive analysis of tense and time in English and Arabic

Summary available; p. xxxi - xxxii

Molybdenum (VI) imido complexes derived from chelating phenols : Synthesis, characterization and ɛ-Caprolactone ROP capability

Reaction of the bulky bi-phenols 2,2′-RCH[4,6-(t-Bu)₂C₆H₂OH]₂ (R = Me L¹ᵐᵉH₂, Ph L¹ᵖʰH₂) with the bis(imido) molybdenum(VI) tert-butoxides [Mo(NR¹)(NR²)(Ot-Bu)₂] (R¹ = R² = 2,6-C₆H₃-i-Pr₂; R¹ = t-Bu, R² = C₆F₅) afforded, following the successive removal of tert-butanol, the complexes [Mo(NC₆H₃ᵢ-Pr₂-2,6)₂L¹ᵐᵉ] (1), [Mo(NC₆H₃i-Pr₂-2,6)₂L¹ᵖʰ] (2) and [Mo(Nt-Bu)(μ-NC₆F₅)(L¹ᵐᵉ)]₂ (3). Similar use of the tri-phenol 2,6-bis(3,5-di-tert-butyl-2-hydroxybenzyl)-4-methylphenol (L²H₃) with [Mo(NC₆H₃ᵢ-Pr₂-2,6)₂(Ot-Bu)₂] afforded the oxo-bridged product [Mo(NC₆H₃i-Pr₂-2,6)(NCMe)(μ-O)L2H]₂ (4), whilst use of the tetra-phenols α,α,α′,α′-tetrakis(3,5-di-tert-butyl-2-hydroxyphenyl)-p- or -m-xylene L³ᵖH₄/L³ᵐH₄ led to {[Mo(NC₆H₃ᵢ-Pr₂-2,6)₂]₂(μ-L³ᵖ)} (5) or {[Mo(NC₆H₃ᵢ-Pr₂-2,6)₂]₂(μ-L³ᵐ)} (6), respectively. Similar use of [Mo(NC₆F₅)₂(Ot-Bu)₂] with L³ᵖH₄ afforded, after work-up, the complex {[Mo(NC₆F₅)(Ot-Bu)₂]₂(μ-L³ᵖ)}·6MeCN (7·6MeCN). Molecular structures of 1, 2·CH₂Cl₂, 3, 4·6MeCN, 6·2C₆H₁₄, and 7·6MeCN are reported and these complexes have been screened for their ability to ring open polymerize (ROP) ε-caprolactone; for comparative studies the precursor complex [Mo(NC₆H₃ᵢ-Pr₂-2,6)₂Cl₂(DME)] (DME = 1,2-dimethoxyethane) has also been screened. Results revealed that good activity is only achievable at temperatures of ≥100 °C over periods of 1 h or more. Polymer polydispersities were narrow, but observed molecular weights (Mn) were much lower than calculated values

Detection of Human Torovirus Like Particles and Adenovirus Type F in Children Attending to Babylon Maternity and Children Hospital

Toroviruses are enteric viruses belonging to the Nidovirales order that infect different animal species and human . Torovirus-like particales (TVLPs) that are immunologically related to BRV have been reported as etiological agents of gastroenteritis in humans. The lack of “in vitro” culture systems for toroviruses, except  for the prototype Berne virus or BEV, isolated originally from an infected horse, has hampered their study and the development of diagnostic assays. This  study  describes a real time RT-PCR method to detect  human  torovirus- like particles  (TVLPs) RNA in clinical  stool  samples using primers corresponding to the gene coding for  the nucleocapsid protein which are conserved in all (TVLPs) strains known to date. During this study, the CT value  measured  during real-time PCR analysis was used as an indication of the viral load found in the stool  sample . The assay was evaluated with 72 stool samples from children attending the Babylon maternity and children hospital. Fifty tow out of 72 (72.2%) children were shedding virus at  the time of sample collection, indicating a high incidence of TVLPs  infection  in Babylon Province. This  is the first study  attempted  for   estimating  the presence of TVLPs  in Iraq. The real time RT-PCR assay described in this study  provides a rapid, highly sensitive, specific and reliable detection and quantization  method enabling future TVLPs  epidemiological studies. In addition to that  the study included the development of real-time PCR assays for the detection of group F Adenovirus in 250 stool samples of pediatric subjects  exhibiting symptoms of diarrhea and/ or vomiting  which  were examined. PCR results of 10 positive Adenovirus group F diarrheic stool samples were confirmed by electron microscopy  examination which gave clear positive Adenovirus appearance . Till now there was no successful virus  culture growth for  isolation of diarrhegenic type 40 and 41 grow in routine cell culture . The result of this study by real time reverse transcription  – PCR  assay reflected in 72 .2 % and 58 % torovirus and adenovirus group F respectively. The genotyping results of adenoviruses(genotype 40 and 41)  highlight the significance of rapid molecular methods for the routine screening of stool samples in diagnostic laboratories to provide rapid and efficient methods . Keywords: Human Torovirus, Adenovirus, RT-PCR, Electron Microscopy

Strong Subordination for E -valent Functions Involving the Operator Generalized Srivastava-Attiya

          الموضوع المقدم في هذا البحث  يتضمن التحري عن  بعض العلاقات  وبعض الخواص المهمة  للدوال متعددة التكافوء التي تتعامل مع موثر(( Srivastava-Attiyaالمعمم بواسطة استخدام  مبادئ  التبعية التفاضلية القوية.Some relations of inclusion and their properties are investigated for functions of type " -valent that involves the generalized operator of Srivastava-Attiya by using the principle of strong differential subordination