Assessment of Coefficient of Variation of Emitters Flow Rate with Respect to Design, Manufacturer and Plugging in Installed Drip Irrigation Systems at Selected Sites of Peshawar Valley

The study was conducted to assess the performance of drip irrigation systems installed at Charsadda, Malakand Agency and Nowshera. The performance parameters of the drip irrigation system included the coefficient of variation of emitters flow rate with respect to design of manufacturer, hydraulics, grouping of the emitters, plugging, uniformity, efficiency, adequacy and estimated design discharge , measured Cv(H) values for all plots are less than 30%.  Hydraulic design seems to be only one of the minor factors in the evaluation of overall uniformity of a micro-irrigation system. Having the Cv(HM) variations are only about 0-7% except plot No.1 of Nowshera farm that is 24.16%, expressed by Cv. micro-irrigation system can be designed hydraulically to maintain emitter flow uniformity within 10% or 20% emitter flow variations. Grouping variation of emitters flow is 0-4% in Charsadda and Malakand Agency farm. In plot No.1 of Nowshera farm its 20.60% while in plot No.2 and 3 it is 0%. The group coefficient is affected by emitters flow rate that is uniform. In Charsadda and Malakand Agency farm the overall effect of hydraulic, manufacturer and grouping are 0-7.11% and 0-1.02% in plot No.3 and 2 of Nowshera farm, in plot No.1 it is 31.75%. Among all the factors affecting the uniformity, plugging is the most significant factor. The Cv(P) is 0% resulted from partial plugging. 5-10% plugging could produce Cv(P) of 23-33%. This system has no plugging, which implies that the system is performing excellent. Cv(HMP) was evidently affected most by hydraulic and manufacture variation. The overall Cv(HMP) is maximum in Charsadda plot No.2 is 16.1%  while in plot No.3 and 4 this range from 1.8 to 0.6%. In Malakand and Nowshera farm this overall variation give negative values due to more variation in the level of plugging and CV(HM). . Keywords: Coefficient of Variation, Emitters, Plugging, Uniformity, Drip Irrigatio

Performance Assessment of Existing Drips Irrigation Systems’ Parameters (Uniformity, Efficiency and Adequacy Degree Installed In Selected Sites of Peshawar Valley

The study was conducted to assess the performance of drip irrigation systems installed at Charsadda, Malakand Agency and Nowshera. The performance parameters of the drip irrigation system included the coefficient of variation of emitters flow rate with respect to uniformity, efficiency, adequacy and estimated design discharge by Dadex were compared with physical need based CROPWAT software estimation were evaluated. The emission uniformity in Charsadda farm range from 99.1 to 99.7%. In Malakand Agency farm it range between 96.1 to 97.9% while in Nowshera it range from 86.1 to 100%. Statistical uniformity calculated in Charsadda farm range from 99.3-99.8%. In Malakand Agency it is between 96 –97.3% and 82.8 to 100% in Nowshera farm. Application efficiency of drip system in Charsadda farm is between 88 to 100%. In Malakand it ranges from 67 to 83% while in Nowshera farm it is from 36 to 62%. The storage efficiency is maximum (80.3%) in Malakand Agency farm and minimum in Nowshera farm (24.9%). Charsadda farm has 62.5% average storage efficiency. Adequacy of irrigation having full irrigation of 2.4cm which is he desired depth of application. The adequacy of irrigation for the field in figure 21 is 52.5 percent, since 52.5 percent of the field receives the desired depth of application or more. Keywords: Performance, Drip Irrigation, Application Efficiency, Uniformity, Statistical Uniformity, Coefficient of Global Variation

Surface microstructural changes of spark plasma sintered zirconia after grinding and annealing

Spark plasma sintered zirconia (3Y-TZP) specimens have been produced of 140 nm 372 nm and 753 nm grain sizes by sintering at 1250 °C, 1450 °C and 1600 °C, respectively. The sintered zirconia specimens were grinded using a diamond grinding disc with an average diamond particle size of about 60 µm, under a pressure of 0.9 MPa. The influence of grinding and annealing on the grain size has been analysed. It was shown that thermal etching after a ruff grinding of specimens at 1100 °C for one hour induced an irregular surface layer of about a few hundred nanometres in thickness of recrystallized nano-grains, independently of the initial grain size. However, if the ground specimens were exposed to higher temperature, e.g. annealing at 1575 °C for one hour, the nano-grain layer was not observed. The resulted grain size was similar to that achieved by the same heat treatments on carefully polished specimens. Therefore, by appropriate grinding and thermal etching treatments, nanograined surface layer can be obtained which increases the resistance to low temperature degradation.Peer ReviewedPostprint (author's final draft

High temperature compression of Mo(Si,Al)2-Al2O3 composites

The aim of this study was to investigate the effect on high temperature of mechanical properties of adding Al2O3 particles to polycrystalline Mo(Si,Al)2. Mo(Si,Al)2-Al2O3 composites, containing 0–25 wt% Al2O3 particles have been compression tested at 1300 \ub0C, and the microstructure after deformation was studied using electron backscatter diffraction. It was shown that even small amounts (5 wt%) of Al2O3 particles resulted in a grain-refined material through inhibition of grain growth during sintering, which lead to lower flow stresses compared to the coarse-grained Al2O3-free material. The inverse grain size effect and post-test microstructure investigations suggest that creep-like deformation mechanisms dominate in fine grained Mo(Si,Al)2-Al2O3 composites at 1300 \ub0C. In the materials containing 5–15 wt% Al2O3, the maximum stress decreased with increasing Al2O3 content. In materials with higher Al2O3 additions, the maximum stress increased with the Al2O3 addition, but did not reach the strength levels in the Al2O3-free reference material. It is suggested that the deformation behaviour is affected by electroplasticity effects as resistive heating was used. Electroplasticity contributes to the decrease in maximum stress observed in the lower Al2O3 containing materials, while this is outweighed by particle strengthening at higher Al2O3 contents

High temperature deformation of polycrystalline C40 Mo(Si,Al)2

Polycrystalline Mo(Si,Al)2 with C40 crystal structure was deformed in compression with a strain rate of 10−4 s−1 at 1300 \ub0C. The specimens were deformed to a strain of 10%–15% and showed maximum stresses around 150 MPa prior to pronounced softening. No crack formation or significant increase in porosity could be observed. Post-test microstructure analysis revealed that the material was inhomogeneously deformed on both inter- and intragranular levels. Dynamic recrystallization occurred alongside low angle grain boundary formation in highly deformed grains. Furthermore, complex intragranular deformation fields suggest that slip systems other than 21̄1̄0[0001] may be active during deformation

Optimized cesium and potassium ion-exchanged zeolites A and X granules for biogas upgrading

Partially ion-exchanged zeolites A and X binderless granules were evaluated for CO(2) separation from CH(4). The CO(2) adsorption capacity and CO(2)-over-CH(4) selectivity of binderless zeolites A and X granules were optimized by partial exchange of cations with K(+) and Cs(+), while retaining the mechanical strength of 1.3 MPa and 2 MPa, respectively. Single gas CO(2) and CH(4) adsorption isotherms were recorded on zeolites A and X granules and used to estimate the co-adsorption of CO(2)–CH(4) using ideal adsorbed solution theory (IAST). The IAST co-adsorption analysis showed that the partially ion-exchanged binderless zeolites A and X granules had a high CO(2)-over-CH(4) selectivity of 1775 and 525 respectively, at 100 kPa and 298 K. Optimally ion-exchanged zeolite X granules retained 97% of CO(2) uptake capacity, 3.8 mmol g(−1), after 5 breakthrough adsorption–desorption cycles while for zeolite A ion-exchanged granules the reduction in CO(2) uptake capacity was found to be 18%; CO(2) uptake capacity of 3.4 mmol g(−1). The mass transfer analysis of breakthrough experimental data showed that the ion-exchanged zeolite X had offered a higher mass transfer coefficient, (κ) through the adsorption column compared to zeolite A; 0.41 and 0.13 m s(−1) for NaK(4.5)Cs(0.3)X and CaK(2.5)Cs(0.2)A, respectively

Research of TE behaviour and compression property of porous Ni–Al–Cr intermetallic compounds in the β phase region

Ni–Al–Cr alloys in the β phase (B2–NiAl) region exhibit remarkable stability and mechanical property. Through thermal explosion (TE) reaction, Ni–Al–Cr intermetallic compounds with high porosity can be obtained. In this study, the focus lies on analyzing the macroscopic morphology, microstructure, phase distribution, TE behaviour, and the mechanical property of porous Ni–Al–Cr in the β phase region. Following the TE reaction, the Al-rich sintered product demonstrates a uniform phase composition and high porosity, reaching 44.39%. The vigorous TE reaction promotes the formation of interconnected pores, while the high porosity structure compromises the mechanical properties of the sample. Conversely, the Al-poor sintered product, due to a moderate TE reaction and low porosity structure, maintains its complete morphology and exhibits excellent compression resistance (yield stress reaching 538 MPa). This study offers valuable insights for the fabrication of porous Ni–Al–Cr materials with exceptional structure and performance