The structural, electronic, and optical properties of Cu2Zn1−xBaxSn1−ySiyS4 compounds have been calculated using GGA-PBE function within the framework of Density Functional Theory (DFT). In the present work, lattice p...The structural, electronic, and optical properties of Cu2Zn1−xBaxSn1−ySiyS4 compounds have been calculated using GGA-PBE function within the framework of Density Functional Theory (DFT). In the present work, lattice parameters remained the same, that is tetragonal crystal structure for 0% and 100% doping concentration. The electronic band gap of Cu2Zn1−xBaxSn1−ySiyS4 compounds has been gradually increased for continuous increment of doping concentration where the highest electronic band gap is 1.117 eV for Cu2BaSiS4 structure. Moreover, the band gap changes from direct to indirect band gap with the increase of doping concentration in the parent compound. The absorption coefficient has been found to be high (> 104 cm−1) in UV-region for all the doping concentration which makes the studied compound as a potential candidate of absorber layer in the UV detector. The theoretical study of the effect of double doping in the CZTS compound is very interesting for improving the quality of it and it would be a reference for the theoretical and experimental researchers.展开更多
In the present study, the effect of the exchange-correlation functional on the structural, mechanical, and optoelectronic properties of orthorhombic RbSrBr3 perovskite has been investigated using various functionals i...In the present study, the effect of the exchange-correlation functional on the structural, mechanical, and optoelectronic properties of orthorhombic RbSrBr3 perovskite has been investigated using various functionals in Density Functional Theory (DFT) with the CASTEP code. The optimized lattice parameters are quite similar for all the functionals. The electronic properties have shown that RbSrBr3 perovskite is a wide direct band gap compound with a band gap energy ranging from 4.296 eV to 4.494 eV for all the functionals. The mechanical parameters like elastic constants, Young’s modulus, Shear modulus, Poisson’s ratio, Pugh’s ratio, and an anisotropic factor reveal that the RbSrBr3 perovskite has ductile behavior and an anisotropic nature which signifies the mechanical stability of the compound. The Debye temperature might withstand lattice vibration heat. High absorption coefficient (>104 cm−1), high optical conductivity, and very low reflectivity have been found in the RbSrBr3 perovskite for all functions. The computed findings on the RbSrBr3 perovskite suggested that the presented studied material is potentially applicable for photodetector and optoelectronic devices.展开更多
The experiment was conducted at Plant Genetic Resources Centre, Bangladesh Agricultural Research Institute (BARI) and the genotypes were collected from Chapainawabganj, the most mango variability rich district in Bang...The experiment was conducted at Plant Genetic Resources Centre, Bangladesh Agricultural Research Institute (BARI) and the genotypes were collected from Chapainawabganj, the most mango variability rich district in Bangladesh. The molecular characters of mango germplasm were assessed by using six simple sequence repeat (SSR) markers. Polymerase chain reaction (PCR) amplification of the DNA isolated from 60 mango germplasm with 6 SSR primers was performed. The sizes of the alleles detected ranged from 112 to 221 bp. SSRs exhibited moderate values of polymorphic information content (PIC) range of 0.9405 to 0.6501. Genetic distances (D) between varieties were computed from combined data of the 6 primers, ranging from 0.5000 to 1.0000. Moderate degree of genetic diversity was obtained where the highest level of gene diversity value was noted 0.9433 in loci MIGA179 and the lowest level of gene diversity value was computed 0.6683 in loci MIGA253 with a mean diversity of 0.8842. The dendrogram generated from the unweighed pair group arithmetic average (UPGMA) cluster analysis broadly placed 60 mango cultivars into ten major clusters. The cluster size varied from 1 to 12 and cluster-VI was the largest cluster comprising of 9 cultivars. The tendency of clustering among mango cultivars revealed that they have strong affinity towards further breeding programme.展开更多
This work reports the successful outcomes to process the polyester, acrylic and wool fiber along with jute fiber exclusively using existing jute processing machineries for manufacturing the 241 tex jute blended yarn. ...This work reports the successful outcomes to process the polyester, acrylic and wool fiber along with jute fiber exclusively using existing jute processing machineries for manufacturing the 241 tex jute blended yarn. The blending was performed at feeding stage of breaker carding machine and blending ratio of jute and polyester/acrylic/wool fibers is 80:20. Manufacturing of jute blended yarns will create a new opportunity for extending the uses of jute fibers in value added jute products. The present work is concerned with the investigation of physical properties such as tenacity, elongation % at break, quality ratio, unevenness, imperfections (thick, thin & neps) and hairiness of manufactured jute blended yarns. The jute-polyester (80/20) blended yarn shows the higher strength and more evenness compared to jute-acrylic (80/20), jute-wool (80/20) blended and 100% jute yarn.展开更多
To determine the effect of Biofertilizer and Integrated Pest Management (IPM) biopesticide for controlling foot and root rot diseases of lentil it is very important for conducting experiment in the field. It was marke...To determine the effect of Biofertilizer and Integrated Pest Management (IPM) biopesticide for controlling foot and root rot diseases of lentil it is very important for conducting experiment in the field. It was marked that both Biofertilizer and IPM Biopesticide found significantly lower disease incidence of Bangladesh Institute of Nuclear Agriculture (BINA) released popular lentil variety Binamasur-1 and Binamasur-2 seedlings compared with the control treatment. Soil treatment with Biofertilizer as Bangladesh Agricultural Research Institute (BARI) released Bari-Biofertilizer performed the lowest disease incidence of lentil variety Binamasur-1 and Binamasur-2 at 20 days after sowing (DAS) showed a reduction of disease incidence up to 68.80% and 71.70% over the control. While after 28 DAS, it was found up to 91.27% and 91.34% reduction of disease incidence over control. Furthermore, after 35 DAS, it exhibited up to 69.37% and 69.28% reduction of disease incidence over control. Bari-Biofertilizer significantly increased the fresh weight and the number of nodules per plant.展开更多
Palm fiber (PF) reinforced acrylonitrile butadiene styrene (ABS) composite matrix was prepared by employing Injection Moulding Machine (IMM). Palm fiber was collected from ten different trees of different age group fr...Palm fiber (PF) reinforced acrylonitrile butadiene styrene (ABS) composite matrix was prepared by employing Injection Moulding Machine (IMM). Palm fiber was collected from ten different trees of different age group from Comilla region in Bangladesh. Three sets of samples were prepared for three different wt% (5%, 10% and 20%) of fiber contents. The mechanical (tensile strength, flexural stress, micro hardness, Leeb’s rebound hardness) and physical (bulk density and water absorption) properties were measured. The observed result reveals that the tensile strength (TS) and flexural stress (FS) were decreased with increasing fiber contents in the PF-ABS composites except 10% fiber content.展开更多
Copper zinc tin sulfide(CZTS)thin film was synthesized on soda lime glass substrate by using spin coating method.The synthesized CZTS thin film showed maximum absorption coefficient of 0.193×104 cm-1 and maximum ...Copper zinc tin sulfide(CZTS)thin film was synthesized on soda lime glass substrate by using spin coating method.The synthesized CZTS thin film showed maximum absorption coefficient of 0.193×104 cm-1 and maximum extinction coefficient of 0.011.The direct optical band gap,Urbach energy and steepness parameter of the synthesized CZTS thin film were 1.52 eV,0.52 eV and 0.05 respectively.The CZTS thin film was found to be polycrystalline tetragonal in nature.The scanning electron microscopy(SEM)revealed that the texture structure was formed for the CZTS thin film.展开更多
With the aid of Injection Moulding Machine (IMM) Palm fiber reinforced Acrylonitrile Butadiene Styrene (ABS) composites (PF-ABS) were prepared. Three sets of samples were prepared for three different wt% (5%, 10% and ...With the aid of Injection Moulding Machine (IMM) Palm fiber reinforced Acrylonitrile Butadiene Styrene (ABS) composites (PF-ABS) were prepared. Three sets of samples were prepared for three different wt% (5%, 10% and 20%) of fiber contents. Scanning Electron Microscopy (SEM), X-ray diffraction (XRD) and Fourier Transform Infrared Spectroscopy (FTIR) experiments were performed to study the surface morphology, microstructure (if it crystalline or noncrystalline) and new bond formation after preparation of the composites. SEM pattern shows that after addition of palm fiber in PF-ABS composites the brittleness increased due to creation of voids in the composites except 10% fiber content in PF-ABS. From XRD pattern it is clear that the palm fiber, ABS and PF-ABS composites are amorphous in nature. Moreover FTIR spectrum shows that there is no new bond formed after addition of palm fiber in ABS polymeric matrix to create PF-ABS composites.展开更多
In this work, we demonstrate the synthesis and characterization of Cu-based thin film perovskites and their prospective application in photovoltaic cells and light-harvesting devices, which is lead(Pb) free and enviro...In this work, we demonstrate the synthesis and characterization of Cu-based thin film perovskites and their prospective application in photovoltaic cells and light-harvesting devices, which is lead(Pb) free and environmental friendly. We studied valuable part of graphene for stability issue in CH3NH3CuCl3(MACuCl3) Perovskites solar cell and improved band gap 2.61 eV to 2.56 eV as well. Copper ions represented responsible of this materials for the bright green photoluminescence. For assimilating MACuCl3 and G-MACuCl3 based Perovskites, solar cells architectures and photovoltaic performance are argued among them. The main limitations for the solar cell efficiency were found the arrangement of insubstantial mass and high absorption coefficient of the electrons as well. As per as our knowledge, this work is demonstrated of the prospective of thin film MACuCl3 and G-MACuCl3 perovskite as light absorber and puts down the establishment for additional development of perovskite solar cell as alternative of lead-free materials.展开更多
In this study,cobalt doped ZnS nanoparticles(NPs)have been synthesized by simple chemical precipitation method with six different weight percentages(0.0,0.1,0.3,0.5,0.7 and 1.0%)of cobalt content at room temperature(3...In this study,cobalt doped ZnS nanoparticles(NPs)have been synthesized by simple chemical precipitation method with six different weight percentages(0.0,0.1,0.3,0.5,0.7 and 1.0%)of cobalt content at room temperature(30°C).X-ray diffraction(XRD)patterns of the samples revealed the formation of cubic structure and calculated particle size were found to be nano-sized.Optical band gap values have been obtained from UV-Vis absorption spectra.It has also been found that energy band gap(Eg)increases with the increase in molar concentration of reactant solution and the variation of bandgap was between 5.30-6.01 eV with cobalt doping.展开更多
Natural fiber reinforced composite materials are replacing the conventional materials, owing to their excellent physical, mechanical, electrical, and thermal properties. Also they increase biodegradability, reduce cos...Natural fiber reinforced composite materials are replacing the conventional materials, owing to their excellent physical, mechanical, electrical, and thermal properties. Also they increase biodegradability, reduce cost and decrease environmental pollution and hazards. In this study, obsolete high density polyethylene (HDPE) has used as polymer matrix and banana fiber as reinforcement material. Composites (5%, 10%, 15% and 20% of fiber contents) were made by hot press molding method by using Paul-Otto Weber Hydraulic press machine. The physical, mechanical and thermal properties of banana fiber-HDPE composites were studied and investigated the increment or decrement nature of different properties due to addition of banana fiber in BF-HDPE composites. The bulk density of composites increased with the increase wt. (%) of fiber content in composites. Water absorption ability of banana fiber and BF-HDPE composites also increased with the increase of wt. (%) of fiber content in composites and with socking time. Tensile strength of the BF-HDPE composites increased with the increase of fiber content in both cases (continuous aligned fiber orientation and continuous bidirectional fiber orientation). Moreover, the tensile strength of BF-HDPE composites with continuous aligned fiber orientation was greater than that of continuous bidirectional fiber orientation. At first, the flexural strength increased for 5% BF-HDPE composites then the value decreased for other higher compositions. The flexural strength of continuous aligned fiber orientation was slightly greater than that of continuous bidirectional fiber orientation and composite with 5% banana fiber showed better flexural properties than others. Leeb’s rebound hardness decreased with the increase of fiber addition. Different thermal properties like TG/DTG, DTA of the obsolete HDPE and BF-HDPE composites were studied using thermo gravimetric analyzer and it was found that composite with 20% fiber content was more thermally stable than three other compositions.展开更多
The composite materials are replacing the conventional materials, owing to their excellent properties. The developments of new materials are on the anvil and are thriving day by day. Natural fiber composites such as p...The composite materials are replacing the conventional materials, owing to their excellent properties. The developments of new materials are on the anvil and are thriving day by day. Natural fiber composites such as palm fiber (PF) polymer composites became more enchanting because of their high specific strength, low weight and biodegradability. Mixing of natural fiber like PF with acrylonitrile butadiene styrene (ABS) polymer is finding increased applications. In this work, PF reinforced ABS composites PF-ABS was fabricated by Injection Moulding Machine. The effect of UV-Visible radiation on PF-ABS composites was studied by means of ultraviolet-visible spectroscopy in the wavelength 200 - 1000 nm at room temperature. The present investigation shows that the addition of palm fiber modifies the absorption property of the materials. The absorption ability is maximal for 10% PF-ABS composites while minimal for 20% PF-ABS composites in the visible region of the spectrum. Optical constant like direct band gap energy, Urbach energy and Steepness parameter were determined using absorbance data. The values of direct energy band gap, Urbach energy as well as Steepness parameter were found to be in the range 2.6 - 3.9 eV, 0.40 - 0.85 eV and 0.03 - 0.06, respectively. It was observed that the value of direct band gap energy as well as Urbach energy is higher while the value of Steepness parameter is lower for PF-ABS composites with 10% palm fiber.展开更多
The chronic myeloproliferative neoplasms (CMPN) are a group of clonal hematopoietic stem cell disorders in which large numbers of red blood cells, white blood cells, or platelets grow and spread excess in the bone mar...The chronic myeloproliferative neoplasms (CMPN) are a group of clonal hematopoietic stem cell disorders in which large numbers of red blood cells, white blood cells, or platelets grow and spread excess in the bone marrow and the pe- ripheral blood. Cytogenetic analysis of the t (9:22) and molecular detection of BCR/ABL is the main diagnostic criteria in Philadelphia positive CMPN (CML). The identification of non-receptor tyrosine kinase JAK2 mutations (exon 14 JAK2 V617F and exon 12) have significantly contributed to our understanding of the molecular mechanisms in the pathogenesis of Philadelphia negative CMPN such as polycythemia vera (PV), essential thrombocythemia (ET) and primary myelofibrosis (PMF) patients. According to the revised WHO classification, JAK2 mutation is considered as a major diagnostic and clonal marker in Philadelphia negative CMPN which will play a major role in designing personal- ized treatments for the disease. JAK2 V617F mutation frequency is unknown in Saudi Arabia. Therefore, investigation of the JAK2 V617F mutation was carried out in DNA samples from 78 peripheral blood specimens corresponding to patients with polycythemia vera (PV) (n = 11), Chronic myeloid leukemia (CML) (n = 45), essential thrombocythemia (ET) (n = 10), idiopathic myelofibrosis (MF) (n = 12). We used polymerase chain reaction and direct DNA sequencing to detect the JAK2 mutation. Overall, the incidence of the JAK2 V617F mutation was 91% in PV, 40% in ET, and 25% in MF. This approach proved to be reliable and more sensitive in detecting the mutation. Two essential findings arose from our study. First, this technique could be carried out with DNA samples, even partially degraded, from routinely processed BM or peripheral blood specimens. Second, after correlation with morphological features, it turned out that the characteristics of the megakaryocytes were more specific than the mutational status of JAK2 in characterizing ET and PMF. Concerning PV, as expected, the incidence of the JAK2 mutation was higher, but the morphological criteria were misleading in some cases, strongly suggesting that the combination of both morphology and molecular data would enable the characterization of virtually all cases. JAK2 V617F mutation frequency along with accurate morphological characterization is very reliable tool in diagnosing and classifying CMPN in Saudi patients.展开更多
Biodegradable reinforced composites are playing a vital role in the variety of application for their outstanding performance. Linear Low Density Polyethylene (LLDPE) and Polyethylene Tere-phthalate (PET) blends were p...Biodegradable reinforced composites are playing a vital role in the variety of application for their outstanding performance. Linear Low Density Polyethylene (LLDPE) and Polyethylene Tere-phthalate (PET) blends were prepared by twin screw extruder in different composition. The mechanical properties in 10% PET with LLDPE blend showed the best results where as tensile strength (TS) 9 MPa and percentage elongation at break (%Eb) 33. Cellulose based reinforced PET + LLDPE composite were prepared by compression molding with the optimized jute content 62% that revealed the highest mechanical properties. Cellulose based composites treated with Acacia catechu (AC) solutions (0.1% - 5% w/v) at different soaking time (2 - 20 min.) where observed significant improvement of the mechanical properties. Cellulose treated with 0.1% AC for 2 minutes soaking time depicted the highest mechanical properties and TS is 115% higher than untreated. Composite prepared with 0.1% AC treated showed the best mechanical properties as tensile strength (TS), bending strength (BS), tensile modulus (TM) and bending modulus (BM) were to be 47 MPa, 39 MPa, 1220 MPa and 1784 MPa respectively. The properties of TS, BS, TM and BM were improved as 9%, 30%, 14% and 34% respectively, which were better to untreated composite. Electrical properties such as dielectric constant and loss of the treated and untreated composites were found to be higher dielectric constant of treated jute composite than that of untreated samples. Water uptake and soil degradation of untreated and treated composites performed in significant study. The effect of AC with cellulose composites has found in remarkable changes in the mechanical properties.展开更多
CZTS(copper zinc tin sulfide),Cu_(2)ZnSnS_(4),is a potential demanding candidate that is used as absorber layer in solar cell.The CZTS,Fe^(3+)doped CZTS and CFTS(replacing Zn be Fe^(3+))thin films were deposited on a ...CZTS(copper zinc tin sulfide),Cu_(2)ZnSnS_(4),is a potential demanding candidate that is used as absorber layer in solar cell.The CZTS,Fe^(3+)doped CZTS and CFTS(replacing Zn be Fe^(3+))thin films were deposited on a glass substrate using spin coating technique.The structural and optical properties of all the thin films were studied to investigate the effect of iron doping in CZTS.The XRD(X-ray diffraction)results show that all the thin films grow tetragonal crystal system.The crystallite size of the doped CZTS was higher than the pristine CZTS although it was lowest for CFTS.The optical band gaps varied from 1.45 eV and 1.83 eV which are suitable for absorbing sunlight.展开更多
Fiber-reinforced polymer (FRP) composites have gradually gained wide acceptance as engineering material applications due to their unique advantages including their high strength-to-weight ratio and excellent corrosion...Fiber-reinforced polymer (FRP) composites have gradually gained wide acceptance as engineering material applications due to their unique advantages including their high strength-to-weight ratio and excellent corrosion resistance. This study was carried out with composites prepared by hot press molding method using coconut spathe fiber as reinforcing material and HDPE (from HDPE can as obsolete polymer) as polymer matrix. Composites were made at 150°C under 60 kN load by taking diverse weight percentage (wt.%) of fiber from 0 to 20 of its total weight. In this research investigation, different properties of the composites such as bulk density, water absorption, tensile and flexural properties, impact strength and hardness test properties were carried out. The fiber content enhancement increases the bulk density in all composites. The rate of water absorption improves with the improvement of fiber addition with respect to HDPE in all composites. But the water absorption was not increased uniformly with the increase of fiber addition in composites. In all cases, composites absorbed water very rapidly up to 80 hrs and then water absorption is in saturated condition. The mechanical properties like tensile strength (TS), flexural strength (FS), impact strength (IS) and hardness were observed to be comparatively more enhanced for 5% composite, while further increasing of fiber addition, all mechanical properties changes irregularly. The irregular nature of change might be caused due to the over loading of fiber in polymer matrix.展开更多
The sawdust reinforced Acrylonitrile Butadiene Styrene (ABS) composites were prepared by using hot press molding machine for five different wt% (0%, 5%, 10%, 15% and 20%) at 180<span style="white-space:nowrap;...The sawdust reinforced Acrylonitrile Butadiene Styrene (ABS) composites were prepared by using hot press molding machine for five different wt% (0%, 5%, 10%, 15% and 20%) at 180<span style="white-space:nowrap;">°</span>C temperature and 50 KN load. Sawdust was collected from local saw mill of Savar, Dhaka, Bangladesh and ABS polymer was collected from local market of Dhaka, Bangladesh. In this study, different properties of composites like physical (bulk density and water absorption), mechanical (tensile properties and hardness) and structural (Fourier Transform Infrared Spectroscopy) properties were studied. The bulk density of composites was not altered consistently and it gave greater value for 5% and 20% composites. The water absorption enhanced for all composites with the accumulation of fiber content and soaking time. The reduction of tensile strength and Leeb’s rebound hardness of the composites were observed with the increase of the fiber content in all compositions. Maximum (%) of elongation was found for 5% composite, and then it gradually decreased;however, elastic modulus increased with the increased of fiber content in composites. Fourier Transform Infrared (FTIR) spectroscopy study was done for structural characterization. It was found that there was a new bond (C≡C) stretching formed for 20% composite;moreover, C-H rocking for 0% composite was broken for all other composites after the addition of sawdust in ABS polymer matrix.展开更多
Sunitinib is an orally administered, multi-target tyrosine kinase inhibitor that has been approved by the FDA for the treatment of renal cell carcinoma and imatinib resistant gastro-intestinal tumors. Anti-leukemic ac...Sunitinib is an orally administered, multi-target tyrosine kinase inhibitor that has been approved by the FDA for the treatment of renal cell carcinoma and imatinib resistant gastro-intestinal tumors. Anti-leukemic activity of sunitinib has been examined in early clinical trials with limited success. However, recent trials on acute myeloid leukemia (AML) patients carrying FLT3 mutations have shown promising results. Effects of sunitinib on leukemic clonogenic cells and potential leukemic stem cells have not been examined so far. We analyzed the anti-proliferative and apoptotic properties of sunitinib on AML-derived cell lines. We also tested the effect of sunitinib on AML patient derived clonogenic cells (AML-CFC), as well as flow-sorted potential leukemic progenitors. Peripheral blood or bone marrow samples were obtained from newly diagnosed AML patients and flow sorted for CD34+ CD133+ or ALDH+ cells. Umbilical cord blood derived CD34+ cells were used as normal controls. Sunitinib induced growth arrest and apoptosis in AML derived cell lines. In addition, 7 μM sunitinib induced 75% reduction of AML-CFC as compared to DMSO treated control (±6.79%;n = 4). In contrast, 7 μM sunitinib treatment of umbilical cord blood derived normal CD34+ cells showed 29% reduction in AML-CFC (±6.77%;n = 5). Treatment of ALDH+ cells sorted from 2 AML cases and CD34+ CD133+ cells from one patient showed reduction of AML-CFC on treatment with sunitinib. Our study highlighted a potent anti-proliferative and proapoptotic effect of sunitinib on AML cell lines, AML patient derived clonogenic cells and potential leukemic stem cells.展开更多
In the recent decade,GO has emerged as an amazing 2D nanomaterial for developing DNA-based biosensors due to its fluorescence quenching properties,whereas similar research based on rGO was reported rarely.Herein,a nov...In the recent decade,GO has emerged as an amazing 2D nanomaterial for developing DNA-based biosensors due to its fluorescence quenching properties,whereas similar research based on rGO was reported rarely.Herein,a novel multi-pyrene functionalized G-rich DNA probe based on the screened rGO showed much higher fluorescence quenching efficiency and excimer emission than that of universal GO.Different from the universal thrombin detection of the G4-forming aptamer-TBA(GGTTGGTGTGGTTGG),the original telomeric sequence is used in this study.The excimer emission“ON-OFF”switch amplified the response of thrombin detection is as low as 50 units.Furthermore,for four pyrene moieties that are sited in a crowded steric circumstance,the melting temperature(T_(m))values and molecular dynamics simulations showed a positive effect on duplex G-quadruplex or _(G)DNA·_(c)DNA stability,without disturbing its helix structure.展开更多
文摘The structural, electronic, and optical properties of Cu2Zn1−xBaxSn1−ySiyS4 compounds have been calculated using GGA-PBE function within the framework of Density Functional Theory (DFT). In the present work, lattice parameters remained the same, that is tetragonal crystal structure for 0% and 100% doping concentration. The electronic band gap of Cu2Zn1−xBaxSn1−ySiyS4 compounds has been gradually increased for continuous increment of doping concentration where the highest electronic band gap is 1.117 eV for Cu2BaSiS4 structure. Moreover, the band gap changes from direct to indirect band gap with the increase of doping concentration in the parent compound. The absorption coefficient has been found to be high (> 104 cm−1) in UV-region for all the doping concentration which makes the studied compound as a potential candidate of absorber layer in the UV detector. The theoretical study of the effect of double doping in the CZTS compound is very interesting for improving the quality of it and it would be a reference for the theoretical and experimental researchers.
文摘In the present study, the effect of the exchange-correlation functional on the structural, mechanical, and optoelectronic properties of orthorhombic RbSrBr3 perovskite has been investigated using various functionals in Density Functional Theory (DFT) with the CASTEP code. The optimized lattice parameters are quite similar for all the functionals. The electronic properties have shown that RbSrBr3 perovskite is a wide direct band gap compound with a band gap energy ranging from 4.296 eV to 4.494 eV for all the functionals. The mechanical parameters like elastic constants, Young’s modulus, Shear modulus, Poisson’s ratio, Pugh’s ratio, and an anisotropic factor reveal that the RbSrBr3 perovskite has ductile behavior and an anisotropic nature which signifies the mechanical stability of the compound. The Debye temperature might withstand lattice vibration heat. High absorption coefficient (>104 cm−1), high optical conductivity, and very low reflectivity have been found in the RbSrBr3 perovskite for all functions. The computed findings on the RbSrBr3 perovskite suggested that the presented studied material is potentially applicable for photodetector and optoelectronic devices.
文摘The experiment was conducted at Plant Genetic Resources Centre, Bangladesh Agricultural Research Institute (BARI) and the genotypes were collected from Chapainawabganj, the most mango variability rich district in Bangladesh. The molecular characters of mango germplasm were assessed by using six simple sequence repeat (SSR) markers. Polymerase chain reaction (PCR) amplification of the DNA isolated from 60 mango germplasm with 6 SSR primers was performed. The sizes of the alleles detected ranged from 112 to 221 bp. SSRs exhibited moderate values of polymorphic information content (PIC) range of 0.9405 to 0.6501. Genetic distances (D) between varieties were computed from combined data of the 6 primers, ranging from 0.5000 to 1.0000. Moderate degree of genetic diversity was obtained where the highest level of gene diversity value was noted 0.9433 in loci MIGA179 and the lowest level of gene diversity value was computed 0.6683 in loci MIGA253 with a mean diversity of 0.8842. The dendrogram generated from the unweighed pair group arithmetic average (UPGMA) cluster analysis broadly placed 60 mango cultivars into ten major clusters. The cluster size varied from 1 to 12 and cluster-VI was the largest cluster comprising of 9 cultivars. The tendency of clustering among mango cultivars revealed that they have strong affinity towards further breeding programme.
文摘This work reports the successful outcomes to process the polyester, acrylic and wool fiber along with jute fiber exclusively using existing jute processing machineries for manufacturing the 241 tex jute blended yarn. The blending was performed at feeding stage of breaker carding machine and blending ratio of jute and polyester/acrylic/wool fibers is 80:20. Manufacturing of jute blended yarns will create a new opportunity for extending the uses of jute fibers in value added jute products. The present work is concerned with the investigation of physical properties such as tenacity, elongation % at break, quality ratio, unevenness, imperfections (thick, thin & neps) and hairiness of manufactured jute blended yarns. The jute-polyester (80/20) blended yarn shows the higher strength and more evenness compared to jute-acrylic (80/20), jute-wool (80/20) blended and 100% jute yarn.
文摘To determine the effect of Biofertilizer and Integrated Pest Management (IPM) biopesticide for controlling foot and root rot diseases of lentil it is very important for conducting experiment in the field. It was marked that both Biofertilizer and IPM Biopesticide found significantly lower disease incidence of Bangladesh Institute of Nuclear Agriculture (BINA) released popular lentil variety Binamasur-1 and Binamasur-2 seedlings compared with the control treatment. Soil treatment with Biofertilizer as Bangladesh Agricultural Research Institute (BARI) released Bari-Biofertilizer performed the lowest disease incidence of lentil variety Binamasur-1 and Binamasur-2 at 20 days after sowing (DAS) showed a reduction of disease incidence up to 68.80% and 71.70% over the control. While after 28 DAS, it was found up to 91.27% and 91.34% reduction of disease incidence over control. Furthermore, after 35 DAS, it exhibited up to 69.37% and 69.28% reduction of disease incidence over control. Bari-Biofertilizer significantly increased the fresh weight and the number of nodules per plant.
文摘Palm fiber (PF) reinforced acrylonitrile butadiene styrene (ABS) composite matrix was prepared by employing Injection Moulding Machine (IMM). Palm fiber was collected from ten different trees of different age group from Comilla region in Bangladesh. Three sets of samples were prepared for three different wt% (5%, 10% and 20%) of fiber contents. The mechanical (tensile strength, flexural stress, micro hardness, Leeb’s rebound hardness) and physical (bulk density and water absorption) properties were measured. The observed result reveals that the tensile strength (TS) and flexural stress (FS) were decreased with increasing fiber contents in the PF-ABS composites except 10% fiber content.
文摘Copper zinc tin sulfide(CZTS)thin film was synthesized on soda lime glass substrate by using spin coating method.The synthesized CZTS thin film showed maximum absorption coefficient of 0.193×104 cm-1 and maximum extinction coefficient of 0.011.The direct optical band gap,Urbach energy and steepness parameter of the synthesized CZTS thin film were 1.52 eV,0.52 eV and 0.05 respectively.The CZTS thin film was found to be polycrystalline tetragonal in nature.The scanning electron microscopy(SEM)revealed that the texture structure was formed for the CZTS thin film.
文摘With the aid of Injection Moulding Machine (IMM) Palm fiber reinforced Acrylonitrile Butadiene Styrene (ABS) composites (PF-ABS) were prepared. Three sets of samples were prepared for three different wt% (5%, 10% and 20%) of fiber contents. Scanning Electron Microscopy (SEM), X-ray diffraction (XRD) and Fourier Transform Infrared Spectroscopy (FTIR) experiments were performed to study the surface morphology, microstructure (if it crystalline or noncrystalline) and new bond formation after preparation of the composites. SEM pattern shows that after addition of palm fiber in PF-ABS composites the brittleness increased due to creation of voids in the composites except 10% fiber content in PF-ABS. From XRD pattern it is clear that the palm fiber, ABS and PF-ABS composites are amorphous in nature. Moreover FTIR spectrum shows that there is no new bond formed after addition of palm fiber in ABS polymeric matrix to create PF-ABS composites.
文摘In this work, we demonstrate the synthesis and characterization of Cu-based thin film perovskites and their prospective application in photovoltaic cells and light-harvesting devices, which is lead(Pb) free and environmental friendly. We studied valuable part of graphene for stability issue in CH3NH3CuCl3(MACuCl3) Perovskites solar cell and improved band gap 2.61 eV to 2.56 eV as well. Copper ions represented responsible of this materials for the bright green photoluminescence. For assimilating MACuCl3 and G-MACuCl3 based Perovskites, solar cells architectures and photovoltaic performance are argued among them. The main limitations for the solar cell efficiency were found the arrangement of insubstantial mass and high absorption coefficient of the electrons as well. As per as our knowledge, this work is demonstrated of the prospective of thin film MACuCl3 and G-MACuCl3 perovskite as light absorber and puts down the establishment for additional development of perovskite solar cell as alternative of lead-free materials.
文摘In this study,cobalt doped ZnS nanoparticles(NPs)have been synthesized by simple chemical precipitation method with six different weight percentages(0.0,0.1,0.3,0.5,0.7 and 1.0%)of cobalt content at room temperature(30°C).X-ray diffraction(XRD)patterns of the samples revealed the formation of cubic structure and calculated particle size were found to be nano-sized.Optical band gap values have been obtained from UV-Vis absorption spectra.It has also been found that energy band gap(Eg)increases with the increase in molar concentration of reactant solution and the variation of bandgap was between 5.30-6.01 eV with cobalt doping.
文摘Natural fiber reinforced composite materials are replacing the conventional materials, owing to their excellent physical, mechanical, electrical, and thermal properties. Also they increase biodegradability, reduce cost and decrease environmental pollution and hazards. In this study, obsolete high density polyethylene (HDPE) has used as polymer matrix and banana fiber as reinforcement material. Composites (5%, 10%, 15% and 20% of fiber contents) were made by hot press molding method by using Paul-Otto Weber Hydraulic press machine. The physical, mechanical and thermal properties of banana fiber-HDPE composites were studied and investigated the increment or decrement nature of different properties due to addition of banana fiber in BF-HDPE composites. The bulk density of composites increased with the increase wt. (%) of fiber content in composites. Water absorption ability of banana fiber and BF-HDPE composites also increased with the increase of wt. (%) of fiber content in composites and with socking time. Tensile strength of the BF-HDPE composites increased with the increase of fiber content in both cases (continuous aligned fiber orientation and continuous bidirectional fiber orientation). Moreover, the tensile strength of BF-HDPE composites with continuous aligned fiber orientation was greater than that of continuous bidirectional fiber orientation. At first, the flexural strength increased for 5% BF-HDPE composites then the value decreased for other higher compositions. The flexural strength of continuous aligned fiber orientation was slightly greater than that of continuous bidirectional fiber orientation and composite with 5% banana fiber showed better flexural properties than others. Leeb’s rebound hardness decreased with the increase of fiber addition. Different thermal properties like TG/DTG, DTA of the obsolete HDPE and BF-HDPE composites were studied using thermo gravimetric analyzer and it was found that composite with 20% fiber content was more thermally stable than three other compositions.
文摘The composite materials are replacing the conventional materials, owing to their excellent properties. The developments of new materials are on the anvil and are thriving day by day. Natural fiber composites such as palm fiber (PF) polymer composites became more enchanting because of their high specific strength, low weight and biodegradability. Mixing of natural fiber like PF with acrylonitrile butadiene styrene (ABS) polymer is finding increased applications. In this work, PF reinforced ABS composites PF-ABS was fabricated by Injection Moulding Machine. The effect of UV-Visible radiation on PF-ABS composites was studied by means of ultraviolet-visible spectroscopy in the wavelength 200 - 1000 nm at room temperature. The present investigation shows that the addition of palm fiber modifies the absorption property of the materials. The absorption ability is maximal for 10% PF-ABS composites while minimal for 20% PF-ABS composites in the visible region of the spectrum. Optical constant like direct band gap energy, Urbach energy and Steepness parameter were determined using absorbance data. The values of direct energy band gap, Urbach energy as well as Steepness parameter were found to be in the range 2.6 - 3.9 eV, 0.40 - 0.85 eV and 0.03 - 0.06, respectively. It was observed that the value of direct band gap energy as well as Urbach energy is higher while the value of Steepness parameter is lower for PF-ABS composites with 10% palm fiber.
文摘The chronic myeloproliferative neoplasms (CMPN) are a group of clonal hematopoietic stem cell disorders in which large numbers of red blood cells, white blood cells, or platelets grow and spread excess in the bone marrow and the pe- ripheral blood. Cytogenetic analysis of the t (9:22) and molecular detection of BCR/ABL is the main diagnostic criteria in Philadelphia positive CMPN (CML). The identification of non-receptor tyrosine kinase JAK2 mutations (exon 14 JAK2 V617F and exon 12) have significantly contributed to our understanding of the molecular mechanisms in the pathogenesis of Philadelphia negative CMPN such as polycythemia vera (PV), essential thrombocythemia (ET) and primary myelofibrosis (PMF) patients. According to the revised WHO classification, JAK2 mutation is considered as a major diagnostic and clonal marker in Philadelphia negative CMPN which will play a major role in designing personal- ized treatments for the disease. JAK2 V617F mutation frequency is unknown in Saudi Arabia. Therefore, investigation of the JAK2 V617F mutation was carried out in DNA samples from 78 peripheral blood specimens corresponding to patients with polycythemia vera (PV) (n = 11), Chronic myeloid leukemia (CML) (n = 45), essential thrombocythemia (ET) (n = 10), idiopathic myelofibrosis (MF) (n = 12). We used polymerase chain reaction and direct DNA sequencing to detect the JAK2 mutation. Overall, the incidence of the JAK2 V617F mutation was 91% in PV, 40% in ET, and 25% in MF. This approach proved to be reliable and more sensitive in detecting the mutation. Two essential findings arose from our study. First, this technique could be carried out with DNA samples, even partially degraded, from routinely processed BM or peripheral blood specimens. Second, after correlation with morphological features, it turned out that the characteristics of the megakaryocytes were more specific than the mutational status of JAK2 in characterizing ET and PMF. Concerning PV, as expected, the incidence of the JAK2 mutation was higher, but the morphological criteria were misleading in some cases, strongly suggesting that the combination of both morphology and molecular data would enable the characterization of virtually all cases. JAK2 V617F mutation frequency along with accurate morphological characterization is very reliable tool in diagnosing and classifying CMPN in Saudi patients.
文摘Biodegradable reinforced composites are playing a vital role in the variety of application for their outstanding performance. Linear Low Density Polyethylene (LLDPE) and Polyethylene Tere-phthalate (PET) blends were prepared by twin screw extruder in different composition. The mechanical properties in 10% PET with LLDPE blend showed the best results where as tensile strength (TS) 9 MPa and percentage elongation at break (%Eb) 33. Cellulose based reinforced PET + LLDPE composite were prepared by compression molding with the optimized jute content 62% that revealed the highest mechanical properties. Cellulose based composites treated with Acacia catechu (AC) solutions (0.1% - 5% w/v) at different soaking time (2 - 20 min.) where observed significant improvement of the mechanical properties. Cellulose treated with 0.1% AC for 2 minutes soaking time depicted the highest mechanical properties and TS is 115% higher than untreated. Composite prepared with 0.1% AC treated showed the best mechanical properties as tensile strength (TS), bending strength (BS), tensile modulus (TM) and bending modulus (BM) were to be 47 MPa, 39 MPa, 1220 MPa and 1784 MPa respectively. The properties of TS, BS, TM and BM were improved as 9%, 30%, 14% and 34% respectively, which were better to untreated composite. Electrical properties such as dielectric constant and loss of the treated and untreated composites were found to be higher dielectric constant of treated jute composite than that of untreated samples. Water uptake and soil degradation of untreated and treated composites performed in significant study. The effect of AC with cellulose composites has found in remarkable changes in the mechanical properties.
文摘CZTS(copper zinc tin sulfide),Cu_(2)ZnSnS_(4),is a potential demanding candidate that is used as absorber layer in solar cell.The CZTS,Fe^(3+)doped CZTS and CFTS(replacing Zn be Fe^(3+))thin films were deposited on a glass substrate using spin coating technique.The structural and optical properties of all the thin films were studied to investigate the effect of iron doping in CZTS.The XRD(X-ray diffraction)results show that all the thin films grow tetragonal crystal system.The crystallite size of the doped CZTS was higher than the pristine CZTS although it was lowest for CFTS.The optical band gaps varied from 1.45 eV and 1.83 eV which are suitable for absorbing sunlight.
文摘Fiber-reinforced polymer (FRP) composites have gradually gained wide acceptance as engineering material applications due to their unique advantages including their high strength-to-weight ratio and excellent corrosion resistance. This study was carried out with composites prepared by hot press molding method using coconut spathe fiber as reinforcing material and HDPE (from HDPE can as obsolete polymer) as polymer matrix. Composites were made at 150°C under 60 kN load by taking diverse weight percentage (wt.%) of fiber from 0 to 20 of its total weight. In this research investigation, different properties of the composites such as bulk density, water absorption, tensile and flexural properties, impact strength and hardness test properties were carried out. The fiber content enhancement increases the bulk density in all composites. The rate of water absorption improves with the improvement of fiber addition with respect to HDPE in all composites. But the water absorption was not increased uniformly with the increase of fiber addition in composites. In all cases, composites absorbed water very rapidly up to 80 hrs and then water absorption is in saturated condition. The mechanical properties like tensile strength (TS), flexural strength (FS), impact strength (IS) and hardness were observed to be comparatively more enhanced for 5% composite, while further increasing of fiber addition, all mechanical properties changes irregularly. The irregular nature of change might be caused due to the over loading of fiber in polymer matrix.
文摘The sawdust reinforced Acrylonitrile Butadiene Styrene (ABS) composites were prepared by using hot press molding machine for five different wt% (0%, 5%, 10%, 15% and 20%) at 180<span style="white-space:nowrap;">°</span>C temperature and 50 KN load. Sawdust was collected from local saw mill of Savar, Dhaka, Bangladesh and ABS polymer was collected from local market of Dhaka, Bangladesh. In this study, different properties of composites like physical (bulk density and water absorption), mechanical (tensile properties and hardness) and structural (Fourier Transform Infrared Spectroscopy) properties were studied. The bulk density of composites was not altered consistently and it gave greater value for 5% and 20% composites. The water absorption enhanced for all composites with the accumulation of fiber content and soaking time. The reduction of tensile strength and Leeb’s rebound hardness of the composites were observed with the increase of the fiber content in all compositions. Maximum (%) of elongation was found for 5% composite, and then it gradually decreased;however, elastic modulus increased with the increased of fiber content in composites. Fourier Transform Infrared (FTIR) spectroscopy study was done for structural characterization. It was found that there was a new bond (C≡C) stretching formed for 20% composite;moreover, C-H rocking for 0% composite was broken for all other composites after the addition of sawdust in ABS polymer matrix.
文摘Sunitinib is an orally administered, multi-target tyrosine kinase inhibitor that has been approved by the FDA for the treatment of renal cell carcinoma and imatinib resistant gastro-intestinal tumors. Anti-leukemic activity of sunitinib has been examined in early clinical trials with limited success. However, recent trials on acute myeloid leukemia (AML) patients carrying FLT3 mutations have shown promising results. Effects of sunitinib on leukemic clonogenic cells and potential leukemic stem cells have not been examined so far. We analyzed the anti-proliferative and apoptotic properties of sunitinib on AML-derived cell lines. We also tested the effect of sunitinib on AML patient derived clonogenic cells (AML-CFC), as well as flow-sorted potential leukemic progenitors. Peripheral blood or bone marrow samples were obtained from newly diagnosed AML patients and flow sorted for CD34+ CD133+ or ALDH+ cells. Umbilical cord blood derived CD34+ cells were used as normal controls. Sunitinib induced growth arrest and apoptosis in AML derived cell lines. In addition, 7 μM sunitinib induced 75% reduction of AML-CFC as compared to DMSO treated control (±6.79%;n = 4). In contrast, 7 μM sunitinib treatment of umbilical cord blood derived normal CD34+ cells showed 29% reduction in AML-CFC (±6.77%;n = 5). Treatment of ALDH+ cells sorted from 2 AML cases and CD34+ CD133+ cells from one patient showed reduction of AML-CFC on treatment with sunitinib. Our study highlighted a potent anti-proliferative and proapoptotic effect of sunitinib on AML cell lines, AML patient derived clonogenic cells and potential leukemic stem cells.
基金supported by the Science and Technology Innovation Commission of Shenzhen,China(Nos.KQJSCX20180328095517269 and JCYJ20210324095607021)。
文摘In the recent decade,GO has emerged as an amazing 2D nanomaterial for developing DNA-based biosensors due to its fluorescence quenching properties,whereas similar research based on rGO was reported rarely.Herein,a novel multi-pyrene functionalized G-rich DNA probe based on the screened rGO showed much higher fluorescence quenching efficiency and excimer emission than that of universal GO.Different from the universal thrombin detection of the G4-forming aptamer-TBA(GGTTGGTGTGGTTGG),the original telomeric sequence is used in this study.The excimer emission“ON-OFF”switch amplified the response of thrombin detection is as low as 50 units.Furthermore,for four pyrene moieties that are sited in a crowded steric circumstance,the melting temperature(T_(m))values and molecular dynamics simulations showed a positive effect on duplex G-quadruplex or _(G)DNA·_(c)DNA stability,without disturbing its helix structure.