Generation of sodium hypochlorite (NaOCl) from sodium chloride solution using C/PbO2 and Pb/PbO2 electrodes

Two modified electrodes (Pb/PbO₂ and C/PbO₂) were prepared by electrodepositing a lead oxide layer on lead and carbon substrates. These modified electrodes were used as anodes for the generation of sodium hypochlorite (NaOCl) from sodium chloride solution. Different operating conditions and factors affecting the treatment process of NaOCl generation, including current density, pH values, conductive electrolytes, and electrolysis time, were studied and optimized. By comparison the C/PbO₂ electrode shows a higher efficiency than the Pb/PbO₂ electrode for the generation of NaOCl.     

On the fly fauna of the central region of the Kingdom of Saudi Arabia: new country records from Riyadh Region,with a list of associated fly species and zoogeographical remarks (Insecta: Diptera)

This study presents three genera and 10 species of flies (order: Diptera) as new country records from the Kingdom of Saudi Arabia (KSA). The flies were identified from Rawdhat Khorim National Park in Riyadh Region, the central region of KSA. The newly recorded genera are Glabellula (Mythicomyiidae), Phora (Phoridae) and Ceroptera (Sphaeroceridae), and the newly recorded species are Dilophus lingens (Bibionidae), Stichopogon deserti (Asilidae), Glabellula sp. (Mythicomyiidae), Phora sp. (Phoridae), Liriomyza lutea (Agromyzidae), Ceroptera aharonii (Sphaeroceridae), Trixoscelis deemingi, Trixoscelis migueli and Trixoscelis puncticornis (Trixoscelididae), and Physiphora leucotricha (Ulidiidae). Glabellula sp. and Phora sp. have been identified only to the genus level and are listed herein only because this is the first time they have been recorded in KSA, and additional specimens are required for their accurate identification to the species level. Also, this is the first record of Trixoscelis deemingi Wo?nica and Trixoscelis migueli Wo?nica from the Palaearctic Region. Distribution, diagnoses, remarks on biology and coloured photos are given for the recorded taxa. A list of associated fly species that were previously recorded in KSA and are identified from the study area in the present study is also presented. Zoogeographically, 33% of the identified fly species showed both Afrotropical and Palaearctic affinities, while 17% were of only Palaearctic affinity, and 8% were of only Afrotropical affinity. Elements from other regions were apparently nil. The results support the idea that the central Arabian Desert, which includes the present study area, is a transitional zone between the Palaearctic and Afrotropical regions.     

A Functional Equation Governing the Motion of a Compressible Fluid Flow

Introduction　　In1952EberhardHopf[1]deducedadynamicalequationgoverningtheevolutionofthecharacteristicfunctionalofaturbulentvelocityfieldinanincompressiblefield,asaconsequenceoftheNavier-Stokesandcontinuityequations.Thepurposeofthispaperistostudythecasewhenthefluidiscompressible.Theword“fluid”denotesanyliquidorgaseousmedium,themostimportantdifferencebetweenthemechanicalpropertiesofliquidsandgasesliesintheirbulkelasticity,thatis,intheircompressibility.Gasescanbecompressedmuchmorethanliquids…     

Processing of peptide and hormone precursors at the dibasic cleavage sites

Many functionally important cellular peptides and proteins, including hormones, neuropeptides, and growth factors, are synthesized as inactive precursor polypeptides, which require post-translational proteolytic processing to become biologically active polypeptides. This is achieved by the action of a relatively small number of proteases that belong to a family of seven subtilisin-like proprotein convertases (PCs) including furin. In view of this, this review focuses on the importance of privileged secondary structures and of given amino acid residues around basic cleavage sites in substrate recognition by these endoproteases. In addition to their participation in normal cell functions, PCs are crucial for the initiation and progress of many important diseases. Hence, these proteases constitute potential drug targets in medicine. Accordingly, this review also discusses the approaches used to shed light on the cleavage preference and the substrate specificity of the PCs, a prerequisite to select which PCs are promising drug targets in each disease.     

对叔丁基杯〔8〕芳烃酯类衍生物的合成

由对叔丁基苯酚和甲醛在碱催化下以一步法合成了对叔丁基杯〔８〕芳烃．以酸酐和酰卤为酰基化试剂合成了相应的酯类衍生物．讨论了杯芳烃的分子结构与光谱性质的关系     

Generalization of Hopf Functional Equation

IntroductionThe techniques ofcharacteristic functionals of fluidmechanical fields are widely used in solving thegeneral problem of turbulence. Thesecharacteristic functionals uniquely define theprobability distributions P(dω) in the phase spaceof turbulent flow,which would give a completesolution of the problem of turbulence.Thetechniques of using a characteristic functional todefine the random field of any fluid dynamicquantity were first pointed out by Kolmogorov(1 93 5 ) ,since then a num…