材料物理与化学进展(英文)最新文献

{"title":"Structural, Magnetic, and Electrical Properties of RE Doped Sr0.82RE0.18Fe12-xAlxO19 (RE = Gd, Pr, Sm) Compound","authors":"D. L. Kunwar, D. Neupane, J. Dahal, S. Mishra","doi":"10.4236/AMPC.2019.99014","DOIUrl":"https://doi.org/10.4236/AMPC.2019.99014","url":null,"abstract":"Among the family of ferrites, M-type hexaferrites \u0000has many industrial applications ranging from simple magnets to microwave \u0000devices. Improvement in magnetic and dielectric properties of ferrites is of \u0000continuous interest. In this present work details study is done to observe the \u0000effect of co-doping of rare-earth (RE3+: Pr3+, Sm3+, and Gd3+) \u0000and aluminum in Sr0.82RE0.18Fe12-xAlxO19 (x = 0.0, 0.5, 1.0, 1.5, 2.0). The adopted samples were synthesized via \u0000autocombustion technique. Detailed synthesis, structural, magnetic, and \u0000electrical measurements of samples were \u0000performed to understand structural-magnetic-electrical property relationship. The Al3+ substitution for Fe3+ brings in a significant enhancement in coercivity but reduces magnetization due \u0000to the magnetic dilution effect. Additional coercivity enhancement was possible \u0000with RE3+ doping without affecting the magnetization of samples. \u0000Among all RE3+ doped samples, Pr3+ doped samples showed the highest Curie temperature, (Tc ~ 465℃), while Gd3+ doped samples showed little variation in dielectric properties in GHz \u0000frequency range. This makes RE3+ doped samples as an ideal candidate \u0000for high-frequency microwave applications. Pr3+ with oblate charge \u0000distribution (negative Stevens constant) was observed to substitute well into \u0000the lattice consequently bringing in desired improvements in physical \u0000properties of Sr0.82RE0.18Fe12-xAlxO19 ferrite.","PeriodicalId":68199,"journal":{"name":"材料物理与化学进展(英文)","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2019-09-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43167606","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Investigation of Nickel Phthalocyanine Thin Films for Solar Cell Applications","authors":"E. M. Nasir, M. Hussein, A. H. Al-Aarajiy","doi":"10.4236/ampc.2019.98013","DOIUrl":"https://doi.org/10.4236/ampc.2019.98013","url":null,"abstract":"Ni-Phthalocyanine thin films were thermally evaporated with different substrate temperatures (300 - 450) K on (silicon wafer, glass) substrates. The chemical bonds of NiPc powder were investigated by FTIR spectrum, which introduce good information for NiPc bonds and their locations. The optical properties have been studied by UV-Visible, and Photoluminescence (PL) Spectra. The NiPc thin films have direct gap for all samples. The values of energy gap which is calculated by PL spectra are lower than those calculated by Tauc equation. It is found there are three activation energies, the mobility and concentration of carriers have been measured and, the NiPc films are p-type. P-NiPc/n-Si HJ solar cell was fabricated at substrates temperatures (300, 400) K. From I-V and C-V characteristic, abrupt junction has been found, photovoltaic characteristics have been observed with Voc of (0.335 - 0.415) V, and Isc of (2.77 - 4.26) μA, and the efficiency of (3.08 - 5.03)% at room temperature and substrate temperature (300, 400 K) and under illumination of 55 mW/cm2 using Halogen lamp. Ideality factors of the junction increase from (0.61 - 0.73) and barrier height increases from 2.53 eV to 3.69 eV while shunt resistance decreases from 3.76 KΩ to 2.59 KΩ and series resistance decreases slightly from 0.24 KΩ to 0.23 KΩ. The fill factor decreases from 0.46 to 0.4 with the increase of substrate temperature.","PeriodicalId":68199,"journal":{"name":"材料物理与化学进展(英文)","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2019-08-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43020015","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The Loading Curve of Spherical Indentions Is Not a Parabola and Flat Punch Is Linear","authors":"G. Kaupp","doi":"10.4236/ampc.2019.98012","DOIUrl":"https://doi.org/10.4236/ampc.2019.98012","url":null,"abstract":"The purpose of this paper is the physical deduction of the loading curves for spherical and flat punch indentations, in particular as the parabola assumption for not self-similar spherical impressions appears impossible. These deductions avoid the still common first energy law violations of ISO 14577 by consideration of the work done by elastic and plastic pressure work. The hitherto generally accepted “parabolas” exponents on the depth h (“2 for cone, 3/2 for spheres, and 1 for flat punches”) are still the unchanged basis of ISO 14577 standards that also enforce the up to 3 + 8 free iteration parameters for ISO hardness and ISO elastic indentation modulus. Almost all of these common practices are now challenged by physical mathematical proof of exponent 3/2 for cones by removing the misconceptions with indentation against a projected surface (contact) area with violation of the first energy law, because the elastic and inelastic pressure work cannot be obtained from nothing. Physically correct is the impression of a volume that is coupled with pressure formation that creates elastic deformation and numerous types of plastic deformations. It follows the exponent 3/2 only for the cones/pyramids/wedges loading parabola. It appears impossible that the geometrically not self-similar sphere loading curve is an h3/2 parabola. Hertz did only deduce the touching of the sphere and Sneddon did not get a parabola for the sphere. The radius over depth ratio is not constant with the sphere. The apparently good correlation of such  parabola plots at large R/h ratios and low h-values does not withstand against the deduced physical equation for the spherical indentation loading curve. Such plots are unphysical for the sphere and so tried regression results indicate data-treatments. The closed physical deduction result consists of the exponential factor h3/2 and a dimensionless correction factor that is depth dependent. The non-parabola against force plot using published data is concavely bent even for large radius/depth-ratios at the shallow indents. The capabilities of conical/pyramidal/wedged indentations are thus lost. These facts are outlined for experimental nano- and micro-indentations. Spherical indentations reveal that linear data regression is suspicious and worthless if it does not correspond with physical reality. This stresses the necessity of the straightforward deductions of the correct relations on the basis of iteration-less and fitting-less undeniable calculation rules on an undeniable basic physical understanding. The straightforward physical deduction of the flat punch indentation is therefore also presented, together with formulas for the physical indentation hardness, indentation work, and applied work for these geometrically self-similar indentations. It is exemplified with a macroindentation.","PeriodicalId":68199,"journal":{"name":"材料物理与化学进展(英文)","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2019-08-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43047164","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The Role of Cooling Condition on the Superconducting Properties of Tl2-xHgxSr2Ca2Cu3O10+δ System","authors":"A. Jassim, M. Alias, M. N. Makadsi","doi":"10.4236/AMPC.2019.98011","DOIUrl":"https://doi.org/10.4236/AMPC.2019.98011","url":null,"abstract":"Solid state reaction method was used to prepare high temperature superconductor with a nominal composition Tl2-xHgxSr2Ca2Cu3O10+δ (0 ≤ x ≤ 1). The effect of quenching on the superconducting properties has been investigated by preparing two sets of samples at 1133 K for 3 hrs. The superconducting properties of the samples have been examined by electrical measurements. It is found that a partial substitution for Tl by Hg increases the formation of high-Tc phase and increases its Tc. X-ray diffraction (XRD) pattern analyses have shown a tetragonal structure, and there are at least two superconducting phases.","PeriodicalId":68199,"journal":{"name":"材料物理与化学进展(英文)","volume":"1 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2019-08-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"42072654","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Impact Thickness on Structural and Electrical Characterization of Nickel Phthalocyanine Thin Films","authors":"E. M. Nasir, M. Hussein, A. H. Al-Aarajiy","doi":"10.4236/AMPC.2019.97010","DOIUrl":"https://doi.org/10.4236/AMPC.2019.97010","url":null,"abstract":"Thin films of Nickel Phthalocyanine have been prepared by evaporation technique for (50 - 350 nm) of thickness. XRD studies show that the thin films have single crystalline structure for low thicknesses with (100) orientation and the crystallite size increased with increased thickness. Also from the AFM technique for NiPc films, the roughness was determined and the grain size increases with increasing of thickness from except at thickness 350 nm. The studies of electrical properties, morphology and orientations of the crystallites are important to understand and predict the nature of the films and essential for their successful applications in solar cell and sensors. The electrical properties of these films were studied with different thickness, NiPc has three activation energy. Carrier’s concentration and mobility was calculated. Hall measurements showed that all the films are p-type.","PeriodicalId":68199,"journal":{"name":"材料物理与化学进展(英文)","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2019-07-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43152625","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Physical Nanoindentation: From Penetration Resistance to Phase-Transition Energies","authors":"G. Kaupp","doi":"10.4236/AMPC.2019.96009","DOIUrl":"https://doi.org/10.4236/AMPC.2019.96009","url":null,"abstract":"-The ISO standard 14577 is challenged for its violation of the energy law, its wrong relation of normal force FN with impression depth h, and for its iterative treatments. The solution of this dilemma is the use of sacrosanct simplest calculation rules for the loading parabola (now FN = kh3/2) giving straight lines for cones, pyramids and wedges. They provide the physical penetration resistance hardness k with dimension [Nm-3/2] and allow for non-iterative calculations with closed formulas, using simple undeniable calculation rules. The physically correct FN versus h3/2 plot is universally valid. It separates out the most common surface effects and reveals gradients. It provides unmatched precision, including reliability checks of experimental data. Regression analysis of FN versus h3/2 plots reveals eventual unsteadiness kink phase-transition onset with the transition-energy. This is shown for all kinds of solid materials, including salts, silicon, organics, polymers, composites, and superalloys. Exothermic and endothermic single and consecutive multiple phase-transitions with their surface dependence are distinguished and the results compared in 5 Tables. The sharp phase-transition onsets and the transition energies provide unprecedented most important materials’ characteristics that are indispensable for safety reasons. ISO ASTM is thus urged to thoroughly revise ISO 14577 and to work out new standards for the mechanically (also thermally) stressed materials. For example, the constancy of the first phase-transition parameters must be controlled, and materials must only be admitted for maximal forces well below the first phase-transition onset. Such onset loads can now be easily calculated. The nevertheless repeated oppositions against the physical analysis of indentations rest on incredibly poor knowledge of basic mathematics, errors that are uncovered. The safety aspects caused by the present unphysical materials’ parameters are discussed.","PeriodicalId":68199,"journal":{"name":"材料物理与化学进展(英文)","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2019-06-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"47501132","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Influence of the Colorless Waste Glass on the Mineralogical, Microstructural and Mechanical Properties of Clay Material from Wack (Adamawa, Cameroon)","authors":"Souaibou, Elimbi Antoine, Danwe Raidandi","doi":"10.4236/AMPC.2019.95008","DOIUrl":"https://doi.org/10.4236/AMPC.2019.95008","url":null,"abstract":"This study reports the investigation of the influence of adding waste glass on the properties of fired clay specimen. Four different particle sizes (smaller than 100 μm, 300μm, 500μm, and 800 μm) of waste glass were mixed with a clay material at contents of 0%, 2%, 6% and 10% per weight. Specimen samples were fired at 750℃ in an electrical furnace for 6 hours, at a heating rate of 5℃/min. The physical and mechanical properties of terracotta are studied. The chemical analysis revealed that the clays were dominated by kaolinite and montmorillonite with small proportion of mixed layers clay. The fine grained texture (0.002 mm > 25%) and high plasticity (WP > 30%) of the clays were responsible for the moderate and high values of shrinkage upon oven drying and firing. The firing color variation from reddish brown shade was due to the amounts of iron and titanium oxides present in the obtained material. The water absorption was varied between 17.40% and 13.70%, while the linear shrinkage was estimated to be between 0.70% and 1.20% and the flexural strength from 5.30 to 8.10 MPa. These results showed that mixing clay with waste glass at 750℃ is an interesting approach to obtain reddish brown ceramics destined for bricks or roofing tiles.","PeriodicalId":68199,"journal":{"name":"材料物理与化学进展(英文)","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2019-05-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"44845491","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"An Effective of Dye Molecules with Cadmium Sulfide Nanorods in Dye Sensitized Solar Cell (DSSCs)","authors":"Entidhar A. Alkuam","doi":"10.4236/AMPC.2019.94004","DOIUrl":"https://doi.org/10.4236/AMPC.2019.94004","url":null,"abstract":"The aligned hexagonal cadmium sulfide nanorods (CdSNR) have been synthe-sized by hydrothermal technique at 200ºC on fluorine tin oxide (FTO) sub-strates. Dye sensitized solar cells (DSSCs) based on the photoelectrode core-shell CdSNR array with conductive polymers nanocomposite of polyaniline (PANI) and poly(3,4-ethylenedioxyl-thiophene)/poly(styrene-sulfonate) (PEDOT:PSS) were fabricated and designed with different types of dye molecules. DSSCs were characterized utilizing scanning electron microscopy (SEM), Raman scattering, energy dispersive spectroscopy (EDS), UV-Vis absorption spectroscopy, X-ray diffraction (XRD), and photocurrent-voltage (J-V) characteristic. Results show that under illumination (AM 1.5 G), the high power conversion energy (PCE) was achieved for CdSNR/PANI-PEDOT:PSS device when it sensitized with ruthenium (II) (dye N-719) of 0.91% and a short circuit current density (Jsc) of 4.21 mA/cm2 in comparison with the other devices, which sensitized with natural dyes. The high performance of the CdSNR/PANI-PEDOT:PSS-N719 device attributed to the wide range of absorption and photostability for N719. This work shows that the CdSNR with N719 can be appropriate candidate for photovoltaics device for their low cost fabrication procedure and excellent absorption.","PeriodicalId":68199,"journal":{"name":"材料物理与化学进展(英文)","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2019-04-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43932023","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Effect of Organic Dopants in Dimetallophthalocyanine Thin Films: Application to Optoelectronic Devices","authors":"M. Sánchez-Vergara, Santiago Osorio-Lefler, Pablo Osorio-Lefler, J. R. Alvarez-Bada","doi":"10.4236/AMPC.2019.94007","DOIUrl":"https://doi.org/10.4236/AMPC.2019.94007","url":null,"abstract":"Semiconductor films of organic, doped dimetallophthalocyanine M2Pcs (M = Li, Na) on different substrates were prepared by synthesis and vacuum evaporation. Tetrathiafulvalene (TTF) and tetracyanoquinodimethane (TCNQ) were used as dopants and the structure and morphology of the semiconductor films were studied using IR spectroscopy, X-ray diffraction (XRD), Scanning Electron Microscopy (SEM) and Energy Dispersive X-Ray Spectroscopy (EDS). The absorption spectra recorded in the ultraviolet-visible region for the deposited films showed the Q and Soret bands related to the electronic π-π* transitions in M2Pc molecules. Optical characterization of the films indicates electronic transitions characteristic of amorphous thin films with optical bandgaps between 1.2 and 2.4 eV. Finally, glass/ITO/doped M2Pc/Ag thin-film devices were produced and their electrical behavior was evaluated by using the four-tip collinear method. The devices manufactured from Na2Pc have a small rectifying effect, regardless of the organic dopant used, while the device manufactured from Li2Pc-TCNQ presents ohmic-like behavior at low voltages, with an insulating threshold around 19 V. Parameters such as the hole mobility (μ), the concentration of thermally-generated holes (p0), the concentration of traps per unit of energy (P0) and the total trap concentration (Nt(e)) were also determined for the Li2Pc-TTF device.","PeriodicalId":68199,"journal":{"name":"材料物理与化学进展(英文)","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2019-04-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"44180249","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Phase-Transition Energies, New Characterization of Solid Materials and Anisotropy","authors":"G. Kaupp","doi":"10.4236/AMPC.2019.94006","DOIUrl":"https://doi.org/10.4236/AMPC.2019.94006","url":null,"abstract":"Non-iterative analysis of indentation results allows for the detection of phase transitions under load and their transition energy. The closed algebraic equations have been deduced on the basis of the physically founded normal force  depth3/2 relation. The precise transition onset position is obtained by linear regression of the FN = kh3/2 plot, where k is the penetration resistance, which also provides the axis cuts of both polymorphs of first order phase transitions. The phase changes can be endothermic or exothermic. They are normalized per μN or mN normal load. The analyses of indentation loading curves with self-similar diamond indenters are used as validity check of the loading curves, also from calibration standards that exhibit previously undetected phase-transitions and are thus incorrect. The phase-transition energies for fused quartz are determined from the loading curves from instrument provider handbooks. The anisotropic behavior of phase transition energies is studied for the first time. Quartz is a useful test object. The reasons for the packing-dependent differences are discussed on the basis of the local crystal structure under and around the inserting tip.","PeriodicalId":68199,"journal":{"name":"材料物理与化学进展(英文)","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2019-04-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"46755998","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}