Single Laths Research Articles

Effect of different soil compositions and growth conditions on the corm production of Gladiolus grandiflorus L.

ABSTRACT Gladiolus grandiflorus L. is widely grown in most regions of Pakistan. However, propagules production per unit area is not sufficient. Therefore, pot experiments were undertaken at the Centre of Plant Biodiversity, University of Peshawar during 2021–2022 and 2022–2023 with the aim of investigating the effect of different soil compositions (substrates) and growth conditions on corms and cormels production. The experiment was performed according to two factorial Randomized Complete Block Design (RCBD), repeated twice. For the first time four substrates, i.e. Clay+Silt (2:1), Farmyard manure (FYM)+Clay+Silt (1:1:1), Poultry manure (PM)+Clay+Silt (1:2:2) and PM+FYM+Clay+Silt (1:1:2:2), were used at different growth conditions, i.e. Control, Single lath, Double lath, Plastic and Double lath+Plastic, to explore their effects on corms yield. The FYM+Clay+Silt substrate significantly stimulated number of leaves per plant, leaf area, chlorophyll content, spikes emergence, spike length, plant height, flowers opening, number of florets per spike, number of corms and cormels per plant, fresh weight and diameter of corms in both seasons. The PM+Clay+Silt substrate had shown negative results in the first season. However, this noxious effect was minimised during the second trial. Among growth conditions, Single lath shade significantly enhanced spike length and all corm yielding parameters. Thus, treatments of FYM+Clay+Silt (1:1:1) and Single lath shade were found to be effectual in obtaining the maximum number of corms and cormels of Gladiolus grandiflorus L. in the agro-climatic conditions of Peshawar.

Lathe errors identification based on surface topography analysis after turning

Lathe errors have a great influence on the micro-roughness of machined surface. However, most established methods for lathe errors identification mainly rely on machining tests which are relatively complex and time resuming. These limitations lead to the development of a novel method which identifies lathe errors based on the turning topography with the help of the study of the effect of a single lathe error on the turning surface profile. For this purpose, five types of errors are divided into three categories for their identical effect on turning topography. Discrete Fourier transform (DFT) and least-squares straight line fitting approached to turning surface can respectively predict first two categories errors as well as obtained errors filtering process eventually to get final straightness error. The procedure as well as method verification for error identification are shown in the case study of three groups of simulations.

The simultaneous occurrence of martensitic transformation and reversion of martensite

We use a 3D elastoplastic phase-field model to study the simultaneous occurrence of martensitic transformation as well as the reversion of martensite in steels under uni-axial tension. Our results show that although martensite nucleates and grows as a single lath (variant), it reverts and splits into two independent martensite laths, due to “unfavorable” local stresses.

Veblenite, K2☐2Na(Fe2+5Fe3+4Mn2+7☐)Nb3Ti(Si2O7)2(Si8O22)2O6(OH)10(H2O)3, a new mineral from Seal Lake, Newfoundland and Labrador: mineral description, crystal structure, and a new veblenite Si8O22ribbon

AbstractVeblenite, ideally K2☐2Na(Fe2+5Fe3+4Mn2+7☐)Nb3Ti(Si2O7)2(Si8O22)2O6(OH)10(H2O)3, is a new mineral with no natural or synthetic analogues. The mineral occurs at Ten Mile Lake, Seal Lake area, Newfoundland and Labrador (Canada), in a band of paragneiss consisting chiefly of albite and arfvedsonite. Veblenite occurs as red brown single laths and fibres included in feldspar. Associated minerals are niobophyllite, albite, arfvedsonite, aegirine-augite, barylite, eudidymite, neptunite, Mn-rich pectolite, pyrochlore, sphalerite and galena. Veblenite has perfect cleavage on {001} and splintery fracture. Its calculated density is 3.046 g cm–3. Veblenite is biaxial negative with α 1.676(2), β 1.688(2), γ 1.692(2) (λ 590 nm), 2Vmeas= 65(1)°, 2Vcalc= 59.6°, with no discernible dispersion. It is pleochroic in the following pattern:X= black,Y= black,Z= orange-brown. The mineral is red-brown with a vitreous, translucent lustre and very pale brown streak. It does not fluoresce under short and long-wave UV-light. Veblenite is triclicnic, space groupP,a5.3761(3),b27.5062(11),c18.6972(9) Å, α 140.301(3), β 93.033(3), γ 95.664(3)°,V= 1720.96(14) Å3. The strongest lines in the X-ray powder diffraction pattern [d(Å)(I)(hkl)] are: 16.894(100)(010), 18.204(23)(01), 4.271(9)(, 040, 120), 11.661(8)(001), 2.721(3)(), 4.404(3)(,), 4.056(3)(031, 12;,), 3.891(2)(003).The chemical composition of veblenite from a combination of electron microprobe analysis and structural determination for H2O and the Fe2+/Fe3+ratio is Nb2O511.69, TiO22.26, SiO235.71, Al2O30.60, Fe2O310.40, FeO 11.58, MnO 12.84, ZnO 0.36, MgO 0.08, BaO 1.31, SrO 0.09, CaO 1.49, Cs2O 0.30, K2O 1.78, Na2O 0.68, H2O 4.39, F 0.22, O = F –0.09, sum 95.69 wt.%. The empirical formula [based on 20 (Al+Si) p. f. u. is (K0.53Ba0.28Sr0.03☐0.16)Σ1(K0.72Cs0.07☐1.21)Σ2(Na0.72Ca0.17☐1.11)Σ2(Fe2+5.32Fe3+4.13Mn2+5.97Ca0.70Zn0.15Mg0.07☐0.66)Σ17(Nb2.90Ti0.93Fe3+0.17)Σ4(Si19.61Al0.39)Σ20O77.01H16.08F0.38. The simplified formula is (K, Ba, ☐)3(☐, Na)2(Fe2+, Fe3+, Mn2+)17(Nb,Ti)4(Si2O7)2(Si8O22)2O6(OH)10(H2O)3. The infrared spectrum of the mineral contains the following bands (cm–1): 453, 531, 550, 654 and 958, with shoulders at 1070, 1031 and 908. A broad absorption was observed between ~3610 and 3300 with a maximum at ~3525. The crystal structure was solved by direct methods and refined to anR1index of 9.1%. In veblenite, the main structural unit is an HOH layer, which consists of the octahedral (O) and two heteropolyhedral (H) sheets. The H sheet is composed of Si2O7groups, veblenite Si8O22ribbons and Nb-dominant D octahedra. This is the first occurrence of an eight-membered Si8O22ribbon in a mineral crystal structure. In the O sheet, (Fe2+, Fe3+, Mn2+) octahedra share common edges to form a modulated O sheet parallel to (001). HOH layers connectviacommon vertices of D octahedra and cations at the interstitialA(1,2) andBsites. In the intermediate space between two adjacent HOH layers, theA(1) site is occupied mainly by K; theA(2) site is partly occupied by K and H2O groups, theBsite is partly occupied by Na. The crystal structure of veblenite is related to several HOH structures: jinshanjiangite, niobophyllite (astrophyllite group) and nafertisite. The mineral is named in honour of David R. Veblen in recognition of his outstanding contributions to the fields of mineralogy and crystallography.

Effect of Two-Phase Region Quenching Temperature on Microstructure Evolution and Microhardness of HSLA100 Steel

The microstructure evolution characteristics and those effects on microhardness of HSLA (high strength low alloy) 100 steel secondary quenched in the two-phase region were investigated. The results show that the mixed microstructure of ferrite and the M-A（mastenite-austenite）islands can be obtained in the intercritical quenching region. A small amount of island structure distributing along the lath ferrite quenched at 700°C is observed by transmission electron microscope (TEM). With the quenching temperature increasing, the island structure increases in quantity and coarsens in shape, at the same time, the ferrite gradually transform from single lath morphology to polygonal shape with the dislocation density lowing. When quenched at 820°C, the microstructure reverts to lath bainite. There is a good correlation between Vickers hardness value and the volume fraction of martensite or bainite HSLA100 steel quenched in the two-phase region. The microhardness value of the steel continually increase from 240HV to 320HV quenched at the range of 700°C to 820°C, and then keep a very small fluctuation around 320HV when the temperature exceeds to 820°C.

Phlogopite and quartz lamellae in diamond‐bearing diopside from marbles of the Kokchetav massif, Kazakhstan: exsolution or replacement reaction?

AbstractExsolution lamellae of pyroxene in garnet (grt), coesite in titanite and omphacite from UHPM terranes are widely accepted as products of decompression. However, interpretation of oriented lamellae of phyllosilicates, framework silicates and oxides as a product of decompression of pyroxene is very often under debate. Results are presented here of FIB‐TEM, FEG‐EMP and synchrotron‐assisted infrared (IR) spectroscopy studies of phlogopite (Phlog) and phlogopite + quartz (Qtz) lamellae in diamond‐bearing clinopyroxene (Cpx) from ultra‐high pressure (UHP) marble. These techniques allowed collection of three‐dimensional information from the grain boundaries of both the single (phlogopite), two‐phase lamellae (phlogopite + quartz), and fluid inclusions inside of diamond included in K‐rich Cpx and understanding their relationships and mechanisms of formation.The Cpx grains contain in their cores lamellae‐I, which are represented by topotactically oriented extremely thin lamellae of phlogopite (that generally are two units cell wide but locally can be seen to be somewhat broader) and microdiamond. The core composition is: (Ca0.94K0.04Na0.02) (Al0.06Fe0.08Mg0.88) (Si1.98Al0.02)O6.00. Fluid inclusions rich in K and Si are recognized in the core of the Cpx, having no visible connections to the lamellae‐I. Lamellar‐II inclusions consist of micron‐size single laths of phlogopite and lens‐like quartz or slightly elongated phlogopite + quartz intergrowths; all are situated in the rim zone of the Cpx. The composition of the rim is (Ca0.95Fe0.03Na0.02) (Al0.05Fe0.05Mg0.90)Si2O6, and the rim contains more Ca, Mg then the core, with no K there. Such chemical tests support our microstructural observations and conclusion that the phlogopite lamellae‐I are exsolved from the K‐rich Cpx‐precursor during decompression. It is assumed that Cpx‐precursor was also enriched in H2O, because diamond included in the core of this Cpx contains fluid inclusions. The synchrotron IR spectra of such diamond record the presence of OH− stretching and H2O bending motion regions. Lamellar‐II inclusions are interpreted as forming partly because of modification of the lamellae‐I in the presence of fluid enriched in K, Fe and Si during deformation of the host diopside; the latter is probably related to the shallower stage of exhumation of the UHP marble. This study emphasizes that in each case to understand the mechanism of lamellar inclusion formation more detailed studies are needed combining both compositional, structural and three‐dimensional textural features of lamellar inclusions and their host.

A GA-based parameter design for single machine turning process with high-volume production

This paper presents a Parameter Design (PD) approach that provides near-optimal settings to the process parameters of a single lathe machine with high-volume production. Optimized process parameters include both machining parameters (cutting speed, feed rate, and depth of cut) and production parameters (material order size and inventory safety stock and reorder point). In high-volume production, machining parameters have amplified impacts on the machine performance in terms of productivity (cycle time), reliability (tool life), and product quality (surface finish). In addition, production parameters become critical in high-volume production since they directly impact the overall order fulfillment (production makespan and delivery reliability). Hence, this paper extends the conventional per-part machining cost model into a per-order production cost model by consolidating the production economics of both machining parameters and production controls. Discrete Event Simulation (DES) is utilized to capture the stochastic and dynamic production attributes and to transfer the static machine PD model into a dynamic PD-DES production model. The model is also utilized to accumulate the per-order running cost over production time while incorporating the impacts of process variability in tool life, labor efficiency, machining conditions, order lead time, and demand rate. Using the PD-DES model as a dynamic fitness function, a Simple Genetic Algorithm (SGA) is developed and applied to a CNC lathe machine to determine near-optimal settings to both machining and production process parameters so that the overall per-order production cost is minimized. Results showed effective SGA convergence profile with relatively low number of search generations. Sensitivity analysis with SGA parameters is conducted to demonstrate the search’s robustness. The benefits of the per-order cost model are illustrated by repeating the SGA solution using machine productivity as a fitness criterion. The new SGA solution resulted in a better productivity but at a higher per-order cost. Finally, the effectiveness of SGA search is illustrated by outperforming the solutions obtained from two-level and three-level full factorial designs.

Clay Translocation in the Artificial Recharge of a Groundwater System in the Southern Zagros Mountains, Iran

The shortage of water in Iran and most countries in the arid and semiarid zones is approaching the critical stage. Because about 60% of the water used in Iran is supplied by underground resources and natural recharge cannot replace the amount of water exploited, artificial recharge of groundwater (ARG) is actively pursued in this country. Desiltation of turbid floodwaters in sedimentation basins is a prerequisite for ARG. It is executed close to the heads of alluvial fans on an extensive area in Iran. Because the sediment removal efficiency of sedimentation basins is not 100%, downward migration of some clay particles, both in sedimentation basins and recharge ponds, causes the gradual impermeability and eventual clogging of the vadose zone and reduces the economic life of the recharge systems. Coarse-grained alluvium beneath 2 sedimentation basins, one in operation for 13 years and the other for 11 years, was sampled down to a depth of 7.5 m. Sampling was repeated in a control area outside and adjacent to the ARG system. X-ray diffraction patterns clearly show the presence of illite, chlorite, kaolinite, smectite, and sepiolite. Single laths and bundles of laths of palygorskite–sepiolite, a well-formed 6-sided and a pseudohexagonal flake of kaolinite, and smectite particles with smooth, wavy edges are clearly seen in the transmission electron micrograph. The order of clay mineral accumulation at a depth of 7.5 m was as follows: sepiolite > palygorskite > chlorite. The relatively high concentration of sepiolite may indicate its neoformation in the rooting zone of river red gum (Eucalyptus camaldulensis Dehnh.).

The morphology and crystallography of Ferrous lath martensite. Studies of Fe-20%Ni-5%Mn—III. Surface relief, the shape strain and related features

Surface relief features associated with single laths and groups of laths of martensite formed in an Fe-20Ni-5Mn alloy were studied by optical, interference and scanning electron microscopy. Unlike ferrous martensites with a plate morphology, the formation of lath martensite gives rise to extensive accommodation distortion both within the martensite and in the adjacent austenite. The regions of accommodation strain in the austenite may enhance the formation of other lath variants. Because of accommodation strains and, in addition, the small intrinsic lath size (typically only 0.3 μm wide) refined measurements of the martensite shape strain proved to be difficult. Nevertheless, the same sense of the shape deformation was found for both isolated laths or groups of laths in a packet having the same habit plane variant and the results obtained suggest that the majority of the shear component of the martensite shape strain is along the width rather than the long dimension of the laths. Shape strain magnitudes as large as m = 0.33 were estimated, in marked contrast to values m = 0.21 usually observed for plate-like martensite in iron alloys and steels. The present results and experimental conditions do not preclude even higher values of the shape strain magnitude for lath martensite. It is inferred that the rather high shape strain associated with lath martensite may underly the observed extensive accommodation strain and intrinsic morphology of the laths (as contrasted to plates).