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Synthesizing hydrosulfido Cu thiolate complexes is quite challenging. In this report, two new and rare hydrosulfido Cu thiolate complexes, [Et

Service rules make it easier for an institution to pursue higher education. In order to ensure quality education, it is essential that educational institutions have service rules. The service rules of university employment are considered to be conducive to the higher education system. On this article discusses the importance of service rules. Each step of the service rules is shown with the help of diagrams and each of the steps is discussed separately. To certify higher education has played a noteworthy part in Bangladesh. The rules clearly specify the rights and duties of workers and employers where every institution must have its own service rules regulating any employment but cannot be contradictory to any establishment of the labor laws. Job satisfaction is considered as a vital determinant of job activities. Some of the universities are providing quality education but rests of them are not quality concerned, most of them are depending on Daily basis teachers, poor infrastructures, without service rules etc. The trial was taken on a random basis from four private universities in Bangladesh. The sample size is forty-five. The result of this study shows that about job satisfaction level of employees in the selected universities. In the end, based on results, researchers have offered some suggestions that can be taken into thought in strategy level.

Constructing synthetic models of the nitrogenase PN -cluster has been a long-standing synthetic challenge. Here, we report an optimal nitrogenase PN -cluster model [{(TbtS)(OEt2 )Fe4 S3 }2 (μ-STbt)2 (μ6 -S)] (2) [Tbt=2,4,6-tris{bis(trimethylsilyl)methyl}phenyl] that is the closest synthetic mimic constructed to date. Of note is that two thiolate ligands and one hexacoordinated sulfide are connecting the two Fe4 S3 incomplete cubanes similar to the native PN -cluster, which has never been achieved. Cluster 2 has been characterized by X-ray crystallography and relevant physico-chemical methods. The variable temperature magnetic moments of 2 indicate a singlet ground state (S=0). The Mossbauer spectrum of 2 exhibits two doublets with an intensity ratio of 3:1, which suggests the presence of two types of iron sites. The synthetic pathway of the cluster 2 could indicate the native PN -cluster maturation process as it has been achieved from the Fe4 S4 cubane Fe4 S4 (STbt)4 (1).

University leadership means the overall state of the administrative structure of a university which many universities in Bangladesh and the world have failed to meet this demand. In this paper, the researcher goes on to show how effective authority of a university can be built and the survey further shows how important effective authority of a university. University leadership and administration is a serious characteristic as it is about the effective of the whole institution. Leading promoters encourage transformational leadership, moral stewardship, principal as an instructional leader, and principal as a communicator or community builder. Effective and capable administration of the university relies on the principal. Leadership effectiveness is more related to situational leadership style in research universities and in a global framework. Hence, training and advance in university leadership involves a systematic planning which will result to outstanding institution.

Ligands are almost essential in the synthesis of nanostructures. In this work, we introduce the alkynyl ligands into the synthesis of ultrathin gold (Au) nanowires arrays. The strong binding affinity of the alkynyl ligands enables one-dimensional (1D) growth via the active surface growth mechanism. The scope of the ligand generality was systematically investigated, and the alkynyl ligand-induced nanowire growth processes were compared and contrasted with those involving thiolated ligands. While strong ligands are usually difficult to dissociate from the nanostructure surface and therefore problematic for post-synthetic processing, the alkynyl ligands are readily dissociable, making the alkynyl ligand-stabilized Au nanowires potentially more modifiable and applicable. As a demonstration, direct palladium (Pd) deposition on the Au nanowires was successfully carried out without any ligand exchange process.

Constructing synthetic models of the nitrogenase P

A new molybdenum complex, [Et4N]2[Mo(PPh3)(mnt)2–OMo(mnt)2]·CH2Cl2·½H2O (1, mnt = maleonitrile dithiolene = S2C2(CN)2), with unique structural features was synthesized, in which the fragment {Mo(PPh3)(mnt)2–} was attached to another important {–OMo(mnt)2} moiety. The structure of 1 was formed by the association of both the oxo and desoxo motifs of the dimethylsulfoxide reductase (DMSOR) class of enzymes. This dissymmetrical binuclear complex 1 is rare, and it utilized the basic inorganic aspects to accommodate both moieties; under basic conditions, it was converted to (Et4N)2[MoO(mnt)2] (2). Similarly, when treated with PhSH and PPh3, it was completely converted to [Et4N]2[Mo(PPh3)(mnt)2(SPh)] (3) (J. Am. Chem. Soc., 2006, 128, 4196–4197). The chemistry of 1 was analyzed with regard to its synthesis, reactivity, crystal structure, and spectroscopic and photophysical properties. In addition, the results were complemented with DFT calculations.

An experiment was conducted to assess the effect of NPK fertilizers on seedling growth and survival of five important mangrove species of Bangladesh for nine months. Seedlings were raised in the nursery using plastic pots. NPK fertilizers with three treatments (control, 4 gm and 8 gm doses) were used two times when seedlings age was 3 and 6 months. The result showed that seedlings height growth of Excoecaria agallocha was enhanced significantly with the application of NPK fertilizers but it was shown negatively significant effect on height growth of Xylocarpus mekongensis after second time fertilizer application. Moreover, NPK application enhanced mortality of Avicennia officinalis and Ceriops decandra seedlings in both times of fertilizer application. But no effect of NPK fertilizers on seedlings growth and survival of Heritiera fomes were observed.

An unprecedented, super oxidized all-ferric iron-sulfur cubanoid cluster with all terminal thiolates, Fe4 S4 (STbt)4 (3) [Tbt=2,4,6-tris{bis(trimethylsilyl)methyl}phenyl], has been isolated from the reaction of the bis-thiolate complex Fe(STbt)2 (2) with elemental sulfur. This cluster 3 has been characterized by X-ray crystallography, zero-field 57 Fe Mossbauer spectroscopy, cyclic voltammetry, and other relevant physico-chemical methods. Based on all the data, the electronic ground state of the cluster has been assigned to be Stot =0.

Cyanide- and isocyanide-bound molybdenum complexes containing maleonitriledithiolate (mnt = 1,2-dicyanoethylenedithiolate = S2C2(CN)2) as coligands were prepared from the synthon [Et4N]2[MoIVO(mnt)2] (1) as [Et4N][(PPh3)(mnt)23−˙MoIII(μ-CN)MoIII(PPh3)(mnt)23−˙] (3), [Et4N][MoIII(PPh3)(CN)(mnt)23−˙]·CH2Cl2 (4), and [MoIII(CNSiMe3)2(mnt)23−˙](5) using trimethylsilylcyanide (Me3SiCN). Triphenylphosphine (PPh3) was used as a blocking group and also as a competing ligand to cyanide to control the geometry and reactivity for forming the cyanide-bridged molybdenum dimer 3 or with terminal cyanide for the monomer 4. The known tetramer [Et4N]4[MoIII4(μ-CN)4(mnt)8] (2) formed in the absence of PPh3 showed a remarkable reaction with the excess Me3SiCN, where the monomeric species [MoIII(CNSiMe3)2(mnt)2] (5) was formed with Me3SiNC coordination. Overall, the Mo(IV) bis (dithiolate) complex showed diverse reactions with Me3SiCN in the presence and absence of the coligand PPh3 and under protic and aprotic media. The precursor molybdenum complex in the IV oxidation state was reduced to the III state in the complexes 3, 4, and 5, where one of the coordinating chelating ligand mnt2− was oxidized to mnt1−˙. This chemistry was supported by the EPR, electrochemical studies and X-ray crystallography results and corroborated by the DFT level of calculations. The complexes 3 and 4 were blue-emitting materials with a long lifetime in the millisecond range. Further DFT and TD-DFT calculations were carried out to understand the electronic states and the origin of the electronic absorptions.

The study was conducted to identify the reasons behind girl‟s dropout from school in rural areas ofBangladesh and understand the problem to find out possible solutions. A questionnaire survey, casestudy and focus group discussion were selected as study instrumentations which were administered atGolna Union of Saidpur Upazila of Nilphamari district. The study identified some socio-cultural andeconomic reasons behind the girl‟s dropout problem. Economic vulnerability of the families was theprimary reason identified behind the problem. Some other problems identified are like dowry, childmarriage, the unemployment problem, tendencies to get a job at Uttara Export Processing Zone(UEZP) and, insufficient cash support for continuing study. Creating job opportunities throughindustrialization and transferring extra agricultural labour were identified as the best possiblesolutions. Also, immediate steps against the dowry system and child marriage, guide book and tuitionstudy system, engaging Non-Government Organizations (NGOs) in development activities have beenrecommended to mitigate the problem. Solving girl‟s dropout problem warrants a holistic approach,engaging all the possible stakeholders to build a quality education system and a socio-economicallytransformed society for the future generation.

Current research on catalysts for proton exchange membrane fuel cells (PEMFC) is based on obtaining higher catalytic activity than platinum particle catalysts on porous carbon. In search of a more sustainable catalyst other than platinum for the catalytic conversion of water to hydrogen gas, a series of nanoparticles of transition metals viz., Rh, Co, Fe, Pt and their composites with functionalized graphene such as RhNPs@f-graphene, CoNPs@f-graphene, PtNPs@f-graphene were synthesized and characterized by SEM and TEM techniques. The SEM analysis indicates that the texture of RhNPs@f-graphene resemble the dispersion of water droplets on lotus leaf. TEM analysis indicates that RhNPs of p, −0.117 V which is less than that of PtNPs@f-graphene (Ep, −0.380 V) under identical experimental conditions whereas the onset potential of CoNPs@f-graphene was at Ep, −0.97 V and the FeNPs@f-graphene displayed onset potential at Ep, −1.58 V. The pure rhodium nanoparticles, RhNPs also electrocatalyse at Ep, −0.186 V compared with that of PtNPs at Ep, −0.36 V and that of CoNPs at Ep, −0.98 V. The electrocatalytic experiments also indicate that the RhNPs and RhNPs@f-graphene are stable, durable and they can be recycled in several catalytic experiments after washing with water and drying. The results indicate that RhNPs and RhNPs@f-graphene are better nanoelectrocatalysts than PtNPs and the reduction potentials were much higher in other transition metal nanoparticles. The mechanism could involve a hydridic species, Rh-H− followed by interaction with protons to form hydrogen gas.

Introduction Cerebral palsy (CP) is the most common childhood physical disability, with 80% estimated to be in low-middle-income countries. This study aims to (1) determine the accuracy of General Movements (GMs)/Hammersmith Infant Neurological Examination (HINE) for detecting CP at 18 months corrected age (CA); (2) determine the effectiveness of a community-based parent-delivered early intervention for infants at high risk of CP in West Bengal, India (Learning through Everyday Activities with Parents for infants with CP; LEAP-CP). Methods This study comprises two substudies: (1) a study of the predictive validity of the GMs and HINE for detecting CP; (2) randomised, double-blinded controlled trial of a novel intervention delivered through peer trainers (Community Disability Workers, CDW) compared with health advice (15 fortnightly visits). 142 infants at high risk of CP (‘absent fidgety’ GMs; ‘high risk score’ on HINE) aged 12–40 weeks CA will be recruited to the intervention substudy, with infants randomised based on a computer-generated sequence. Researchers will be masked to group allocation, and caregivers and CDWs naive to intervention status. Visits will include therapeutic modules (goal-directed active motor/cognitive strategies and LEAP-CP games) and parent education. Health advice is based on the Integrated Management of Childhood Illness, WHO. Infants will be evaluated at baseline, post intervention and 18 months CA. The primary hypothesis is that infants receiving LEAP-CP will have greater scaled scores on the Pediatric Evaluation of Disability Inventory—Computer Adaptive Test (mobility domain) at 18 months compared with health advice. Secondary outcomes include infant functional motor, cognitive, visual and communication development; infant growth; maternal mental health. Ethics and dissemination This study is approved through appropriate Australian and Indian ethics committees (see in text) with families providing written informed consent. Findings from this trial will be disseminated through peer-reviewed journal publications and conference presentations. Trial registration number 12616000653460p; Pre-results.

The article examines the various ways to ensure land rights and also recommends different mechanism to settle land dispute. It is also intended to highlight the problems of present land administration of Bangladesh and to suggest the reformation of the land administration for proper management of land. Land turns around the life of the people of Bangladesh. The present land laws, land administration and land management in Bangladesh are not only full of intricacy, procedural difficulties and mismanagement but also not accessible and responsive to the interest of the common people of the country. Furthermore, the present mechanism to settle land dispute is not time saving, cost effective, peaceful and sophisticated. If the land laws are made public spirited and land administration is made well-structured in the sense of good governance, e-governance and development, land interest of the common people is upheld and land disputes are settled with public satisfaction and confidence, a revolutionary change may bring about in the socio-economic development of the common people.

Semiconductor quantum dots (QDs) sensitized onto nano TiO2 as heterogeneous photocatalysts have drawn considerable interest over the past few years. However, stability of the QDs attached to TiO2 and consistent photocatalysis are still major challenges of this approach. We describe herein, a facile process to fabricate nanocomposites from porous TiO2 nanowires and bare CdS and core–shell CdS–ZnS QDs, where the QD particles are linked covalently to the titania surface through a bifunctional organic linker, mercapto propionic acid (MPA). A thin layer of ZnS was grown on 6 nm CdS QDs to restrain the photocorrosion and passivate the trap states, enhancing the photoluminescence and quantum yield. The bifunctional linking molecule, MPA, was found to effectively disperse and stabilize the QD nanoparticles. The photocatalytic activities of the prepared catalysts were evaluated under ultraviolet and visible light solar irradiation for the photodegradation of methylene blue (MB), an organic dye. The decomposition rate of MB was enhanced as follows: CdSZnS–MPA–TiO2 > CdS–MPA–TiO2 > CdSZnS–TiO2 > CdS–TiO2 > TiO2 > P25. A maximum photodegradation efficiency of MB dye (∼88%) was obtained by core–shell CdS–ZnS QDs linked with nano TiO2. After 3 cycling tests of degradation, the loss of photoactivity was significantly minimized (from 68% to 10%) by CdSZnS–MPA–TiO2 compared to CdSZnS–TiO2 (by direct deposition).

The development of alternate catalysts that utilize non-precious metal based electrode materials such as the first row transition metal complexes is an important goal for economic fuel cell design. In this direction, a new Fe4S4 cubane type cluster, [PPh4]2[Fe4S4(DMET)4] (1) (DMET = cis-1,2-dicarbomethoxyethylene dithiolate) and its composite with functionalized graphene, (1@graphene) have been synthesized and characterized. The presence of nanocrystalline structures on graphene matrix in TEM and SEM images of 1@graphene indicate that the cluster (1) has been immobilized. The composite, 1@graphene evolves H2 gas from p-toluene sulfonic acid (TsOH) in a mixture of H2O and CH3CN under ambient conditions with a significant turnover number of 3200. 1@graphene electro-catalyzes H2 evolution at Ep, −1.2 V with remarkable throughput, catalytic efficiency and stability in only H2O or in only CH3CN. The Fe4S4 cluster (1) alone electro-catalyzes hydrogen evolution at Ep, −0.75 V from TsOH in CH3CN. The X-ray crystal structure of the Fe4S4 cluster (1) (λmax, CH2Cl2, 823 nm; ε, 2200 mol−1 cm−1) shows that it is dianionic with a cumulative oxidation state of +2.5 for the iron centers and short C-S bond distances (ca., 1.712 Å & 1.727 Å) indicating the presence of sulfur based radicals.

The development of alternate catalysts that utilize non-precious metal based electrode materials such as the first row transition metal complexes is an important goal for economic fuel cell design. In this direction, a new Fe4S4 cubane type cluster, [PPh4]2[Fe4S4(DMET)4] (1) (DMET = cis-1,2-dicarbomethoxyethylene dithiolate) and its composite with functionalized graphene, (1@graphene) have been synthesized and characterized. The presence of nanocrystalline structures on graphene matrix in TEM and SEM images of 1@graphene indicate that the cluster (1) has been immobilized. The composite, 1@graphene evolves H2 gas from p-toluene sulfonic acid (TsOH) in a mixture of H2O and CH3CN under ambient conditions with a significant turnover number of 3200. 1@graphene electro-catalyzes H2 evolution at Ep, −1.2 V with remarkable throughput, catalytic efficiency and stability in only H2O or in only CH3CN. The Fe4S4 cluster (1) alone electro-catalyzes hydrogen evolution at Ep, −0.75 V from TsOH in CH3CN. The X-ray crystal structure of the Fe4S4 cluster (1) (λmax, CH2Cl2, 823 nm; ε, 2200 mol−1 cm−1) shows that it is dianionic with a cumulative oxidation state of +2.5 for the iron centers and short C-S bond distances (ca., 1.712 Å & 1.727 Å) indicating the presence of sulfur based radicals.

The essential sense of the Bail in Bangladesh is to release a person from the custody of police and deliver him/her into the hands of the sureties who undertake to produce him in court whenever required to do so. The word Bail is derived from the old French verb “Bailer” which means to “give” or to “deliver”1 (Webster’s Dictionary, 1938). In common Law legal system, it is found that an accused person is to be declared on bail, when he is released from the custody of the officers of the Court. The sureties are bound to produce him to answer at a specified date, time and place, the accusation against him when bail is approved by the competent court. The basic principle regarding release on bail is that an accused person is presumed in law to be entitled to freedom and every opportunity to look after his case, provided his attendance is secured by proper security. However, the paper focuses the idea of releasing an accused on bail in such a case that has been developed as of right of an accused in our country. Therefore, this paper gives emphasis on bail of an accused on legal analysis on theoretical and practical approach and it recommends that the bail granting authority should maintain the principles of law as well as provisions of law properly for the protection rights of an accused.

Bangladesh is a small country comprising of approximately 147,570 sq. kilometres land territory. But it is an overpopulated country having more than 16 crore citizens. With the boost of population Bangladesh will gradually turn its attention to rich marine resources for food and other needs of its people. It is reported by scientists that resources on sea are much more profile those on land. Since our land-resources are being exhausted gradually, it will be necessary for Bangladesh to depend increasingly on sea resources. This study is intended to highlight the economic benefit may be gained by Bangladesh from its maritime zones as well as focus on the challenges that Bangladesh has to face in achieving the benefit. It is also aimed to make some recommendations how the government of Bangladesh can overcome those challenges.

Three new complexes, [Mo(IV)O(mnt)(SS)](2-) (SS = dimethylethylenedicarboxylate (DMED), toluenedithiolate (tdt), benzenedithiolate (bdt); mnt = maleonitriledithiolate), each possessing two different dithiolene ligands, are synthesized as model of trimethylamine-N-oxide reductase. The asymmetric dithiolene ligands present in these complexes simulate the two different (P and Q) pterin coordinations in the family of DMSO reductase. These complexes reduce trimethylamine-N-oxide ((CH3)3N(+)-O(-) or TMANO), the biological substrate of trimethylamine-N-oxide reductase, to trimethylamine ((CH3)3N), responsible for the fishy smell of dead aquatic animals. The reaction kinetics of trimethylamine-N-oxide reduction by these complexes follow the Michaelis-Menten saturation kinetics. These experimental findings have been rationalized by DFT, TD-DFT level of calculations.

Synthesis of phosphonodithioato complexes of Mo(IV) and W(IV) bis- dithiolene have been reported. These complexes are characterized by elemental analysis, X-ray crystallography, IR, UV–Vis, 31P NMR, and photoluminescence spectroscopy, electrochemical studies and these results are corroborated by DFT level of calculations. Phosphonodithioato ligands is generated in situ from the reaction of Lawesson’s reagent with mono-oxo Mo/W bis dithiolenes complexes resulting its chelation coupled with oxo transfer reaction from M(IV) bound oxo to {P=S} moiety forming (P=O} group. The new complexes are photoluminescent at room temperature.

Dithiobisphthalimide is used as a new precursor for the spontaneous deposition of sulfur on gold surfaces in acetonitrile. Characterization of the modified surfaces is achieved using X-ray photoelectron spectroscopy (XPS), electrochemistry and scanning tunneling microscopy (STM). The reported results indicate that the sulfur deposition is an efficient and fast process and that high coverages can be reached very quickly. Sequential high-resolution STM in air allows the direct observation, for the first time, of the mobility of the usually observed rectangular structures as individual units. It also shows the reversible association/dissociation of these rectangles. The nature of these structures is highly debated in the literature and the present work provides new insights into their nature through the use of a new sulfur precursor under non-traditional conditions. To explain our results we consider these structures as simple sulfur adlayers on the gold surface.

Hydrogen is the ideal fuel because it contains the most energy per gram of any chemical substance and forms water as the only byproduct of consumption. However, storage still remains a formidable challenge because of the thermodynamic and kinetic issues encountered when binding hydrogen to a carrier. In this study, we demonstrate how the principal binding sites in a new class of hydrogen storage materials based on the Kubas interaction can be tuned by variation of the coordination sphere about the metal to dramatically increase the binding enthalpies and performance, while also avoiding the shortcomings of hydrides and physisorpion materials, which have dominated most research to date. This was accomplished through hydrogenation of chromium alkyl hydrazide gels, synthesized from bis(trimethylsilylmethyl) chromium and hydrazine, to form materials with low-coordinate Cr hydride centers as the principal H(2) binding sites, thus exploiting the fact that metal hydrides form stronger Kubas interactions than the corresponding metal alkyls. This led to up to a 6-fold increase in storage capacity at room temperature. The material with the highest capacity has an excess reversible storage of 3.23 wt % at 298 K and 170 bar without saturation, corresponding to 40.8 kg H(2)/m(3), comparable to the 2015 DOE system goal for volumetric density (40 kg/m(3)) at a safe operating pressure. These materials possess linear isotherms and enthalpies that rise on coverage, retain up to 100% of their adsorption capacities on warming from 77 to 298 K, and have no kinetic barrier to adsorption or desorption. In a practical system, these materials would use pressure instead of temperature as a toggle and can thus be used in compressed gas tanks, currently employed in the majority of hydrogen test vehicles, to dramatically increase the amount of hydrogen stored, and therefore range of any vehicle.