Nitrogen dose and sowing density in pea (Pisum sativum L.) crops, to obtain higher yields in Barranca [Dosis de nitrógeno y densidad de siembra del cultivo de arveja (Pisum sativum L.), para obtener mayor rendimiento en Barranca]

The research deals with nitrogen doses and sowing densities in peas. The objective was to determine which nitrogen dose and planting density obtained the highest yield. The methodology is based on applied research; Therefore, the statistical model of the Completely Random Block Design was used, which consisted of 3 blocks and 6 treatments. The doses were applied at 17 days 1/2 N, 100% P2O5 and 100% K2O and 62 days after sowing 1/2 N, it was evaluated from sowing to harvest and the data were processed by analysis of variance of two factors and Duncan, took leaf samples for foliar analysis and determined the total amount of nitrogen used. It was determined that T5 stood out in stem length with 128.42 cm, commercial yield with 12.53 tn/ha, T4 in weight of pods with 620 g, number of pods per plant with 48, T6 in nitrogen concentration with 6.60 g/ 100 g of dry matter and T5 in the amount of nitrogen used with 154.3 kg/ha that obtained the highest yield. It is concluded that the higher dose of nitrogen and less distance that is T5 obtained higher performance exceeding by 24.52% in relation to T1.

Alkaline activation of mortars made from solid construction waste [Activación alcalina de morteros fabricados a partir de residuos sólidos de construcción]

In the present investigation the influence of the percentage by weight of replacement of portland cement (PC) by recycled concrete powder (RCP), alkaline activated, in percentages of 10%, 20%, 30%, 40% and 50%, was evaluated. which were selected from construction rubble left in the Buenos Aires spa, Víctor Larco Herrera district, Trujillo province. After being washed, they went to the grinding and sieving process (400 mesh), using only the through material. Specimens were manufactured according to the ASTM C-109 standard for the compression test in cement mortars, for the alkaline solution NaOH (4M) was used. The mortars obtained were cured in an oven at 70 ° C for 72 hours, and subsequently the curing was completed at room temperature, for a total time of 28 days. The results of the average compression test were 12.15 MPa, in the case of the PC mortar and 14.25 MPa in the best case (PC mortar and RCP-10%), the increase being 17.28%. The mix design using coarse sand and binder was kept constant at (3: 1), while the water / cement ratio (w / c) was 0.6 in all cases. The reason for the increase in compressive strength is due to the reaction between the RCP particles, alkaline solution and the calcium hydroxide produced during the hydration of the cement particles, which generate gels (CASH), which occupy the spaces left by the hydration process of the aforementioned cement particles, as they need calcium hydroxide. For all cases of the compression test, a total of 10 repetitions were carried out.

Didactic and technological tool to encourage study in students of the Systems Engineering School at the National University of Trujillo [Herramienta didáctica y tecnológica para incentivar el estudio en los alumnos de la Escuela de Ingeniería de Sistemas de la Universidad Nacional de Trujillo]

The present research aims to analyze and evaluate a didactic and technological tool and see the impact to encourage study in the students of the Systems Engineering School at the National University of Trujillo, during the 2020-II semester. It was possible to implement the Stormboard application for the development of Brainstorming as a didactic strategy through which it is intended to encourage the creative and innovative aspect of students when addressing topics and case studies. Analyzing the results obtained, we can point out that impacts were determined on the level of motivation for the study of students with a value of 8%, as well as the impact on the level of perception of educational services of students was determined in the order of 24% and finally, results of the impact on the level of student satisfaction were obtained in the order of 17%. Finally, it is proposed that these didactic initiatives be taken into account in the academic and institutional policies of the Systems Engineering School of in order to extrapolate the practice to other academic units at the National University of Trujillo.

Effect of silicon’s doses in the cultivation of pea (Pisum sativum L.), to obtain a higher yield, district of Barranca [Efecto de dosis de silicio en el cultivo de arveja (Pisum sativum L.), para obtener mayor rendimiento, distrito de Barranca]

The objective was to determine the adequate dose of silicon foliar fertilization, to obtain a higher yield in pea crops. Regarding the methodology, the research is applied and experimental; Therefore, the Completely Random Block Design comprised of 4 blocks and 4 treatments was used, which were: T1 = 0, T2 = 0.50 L, T3 = 0.75 L and T4 = 1 L Silicon (Sil Trade) / 200 L of water Applied in four times, it is worth mentioning the chemical ingredient of silicon is orthosilicic acid. The physical characteristics from sowing to harvest were evaluated and the silicon concentrations in leaves were analyzed by treatment. Obtained data were processed by analysis of variance and Duncan. The results determined that T4 stood out in plant height with 89.74 cm, number of pods per plant with 37, weight of pods per plant with 234.43 g, yield with 4444.4 kg/ha and silicon concentration in leaves with 1.75 g/100 g of dry material. It is concluded that there were no silicon effects; that is, it did not statistically influence the physical characteristics. However, T4 with 1 L Silicon (Sil Trade) / 200 L of water increased 8.58% of the yield in relation to T1.

Current density and residence time in the electrocoagulation process and its influence on Fe2+ reduction [Densidad de corriente y tiempo de residencia en el proceso de electrocoagulación y su influencia en la reducción de Fe+2]

The present research work had as study variables the current density of 20, 40 and 80 mA/cm2 and residence times of 10, 20, 40 and 60 minutes, within these evaluation parameters values were taken of pH, conductivity and Fe2+ removal percentage before and after the electrocoagulation process of artisanal acid mine drainage samples (AMD), the amount of AMD sample per test was 350 mL per test, from the results obtained it could be observed that For the current density of 80 mA/cm2 and a time of 40 minutes, the highest percentage of removal was obtained (76.20%), likewise a minimum percentage of removal of 17.97% was obtained at 20 mA/cm2; The removal percentages are attributed to the effect of the current density of the electrocoagulation process, which allows increasing the initial pH values of the effluent, which in turn allows the formation of precipitates and co-precipitates, in this case of Fe2+.

Cold cracking, microstructure, notch toughness, transverse and longitudinal hardness to the weld joint of P460NL1 steel [Fisuracion en frio, microestructura, tenacidad a la entalla, dureza transversal y longitudinal a la union de soldadura del acero P460NL1]

Microstructural development, longitudinal HV10 hardness as transversal to the fusion zone and notch toughness in root and filling pass were evaluated at preheating temperatures of 100 °C, 140 °C, 180 °C, 220 °C and 260 °C in the weld joint of P460NL1 steel, by FCAW in root pass and for filling-finishing by means of the SAW process, the control of the start and interpass preheating temperatures was carried out by thermal blankets and digital pyrometer. The NDT of magnetic particles justify the acceptance or rejection of the specimens for the study. In selected points of the weld joint they showed the dependence of the hardness as a function of the microstructure. At room temperature, immediate cold cracking was observed. In the HAZ, the microconstituents generated areas of high hardness under the cord and areas of low hardness due to overturning, with the presence of Windmastatten ferrite, the increase in preheating determined the decrease and sometimes the absence of hardened structures. The profiles determined a decrease in hardness as the preheating temperature increased. Columnar grains with a high presence of WF ferrite in their different morphologies and FP (C) and refined areas with typical microconstituents were observed in the Fusion Zone. Homogeneity was evidenced with respect to notch toughness at all temperatures and the effect of passes on the longitudinal microstructure, which shows the benefit of the preheating temperature by reducing the hardness in critical areas and homogenizing the welded joint.

Perception on the improvement of attention service to the students under the basic conditions of quality for the institutional licensing of the Private University of Trujillo [Percepción sobre la mejora del servicio de atención a los estudiantes bajo las condiciones básicas de calidad para el licenciamiento institucional de la Universidad Privada de Trujillo]

This research work has been developed with the purpose of evaluating the improvement of the attention service to the students of the Private University of Trujillo with the fulfillment of condition I, component I.4 referring to information systems of the Basic Conditions of Quality (BCQ) to obtain institutional licensing. The indicators used as information systems that involve enrollment, payments, bibliographic material, virtual learning have been used to evaluate the improvement of the attention service to students. The hypothesis was contrasted by applying the pre-experimental design with pre-test and post-test. The result obtained from the significant coefficients of the respective indicators the pre-test was 0.42, 0.15, 0.71, 0.58, 0.35, 0.22, 0.42, 0 and the post-test was 0.93, 1, 0.88, 0.79, 0.88, 0.90, 0.83, 0.67. It was possible to determine that there is no contradiction within each of the indicators, since the results show that in each indicator after using the information systems required in the basic quality conditions, a better service for the students was obtained.

Influence of the virtual teaching modality on the desertion of students from the Computing and Informatics study program in the IESTP Laredo [Influencia de la modalidad de enseñanza virtual en la deserción de los estudiantes del programa de estudios de Computación e Informática en el IESTP Laredo]

The present research work has been developed with the purpose of evaluating the influence of the virtual teaching modality in the dropout of students from the study program of Computación e Informática in IESTP Laredo.The indicators used such as virtual learning, virtual learning systems, didactic units, terminal abilities, have been used to evaluate the degree of student dropout. The hypothesis was contrasted applying the pre-experimental design with pre-test and post-test. The result obtained from the significant coefficients of the respective indicators the pre test was 0,63; 1, 0,65; 0,78; 1; 0,82; 0,78 and the post test was 0,49; 0,61; 0,32; 0,66; 0,65; 0,58; 0,40. It was possible to determine that there is a contradiction within each of the indicators, since the results show that in each indicator at the end of the academic period 2020 - I, a lower participation of students was obtained in the development of the virtual learning process, which leads to dropout using this type of learning.

Thermal stability of water fibers: effect of the alkaline treatment - aminopropyltrimetoxysilane [Estabilidad termica de fibras de aguaje: efecto del tratamiento alcalino – aminopropiltrimetoxysilano]

The present research evaluated the influence of the concentration of sodium hydroxide and aminopropyltrimethoxysilane on the thermal stability of the aguaje fibers. The fibers were extracted by manual immersion in water and subsequent separation by manual pressure. The NaOH concentrations were 5%, 10% and 15% w / v; while in the case of the silane coupling agent they were 1% and 1.5% v / v. The chemically treated fibers together with the control samples were subjected to thermogravimetric analysis evaluation, in addition, the variation of the humidity percentage, the chemical variation of the main functional groups of the fibers and the surface physical changes of the fibers were determined in a complementary way. The mercerization - silanization treatments increase the thermal degradation temperature of the aguaje fibers, in the conditions tested this increase was 3.89% in the best of cases (5% NaOH + 1.0 Silane). Regarding untreated fibers, mercerization - silanization treatments decrease the percentage of lost mass or degradation, in the best of cases this decrease in mass percentage was 26.85% (15% NaOH + 1.5 Silane), compared to fibers without treatment. Finally, mercerization-silanization treatments increase the percentages of cellulose present in the aguaje fibers evaluated, while the amount of extractives and lignin decrease, under the chemical treatment conditions carried out in the present research.

Reduction of hexavalent chrome from artificial effluent of chrome: Batch electrocoagulation method [Reducción del cromo hexavalente de efluente artificial de cromado: Método de electrocoagulación por lotes]

The present research evaluated treatment time, electrode area / effluent volume ratio, on the% reduction of hexavalent chromium in artificial chrome plating effluents, was evaluated by the batch electrocoagulation method; Method for which A-36 steel anodes and cathodes of (5.0 x 5.0 x 0.2) cm were used. The number of electrodes and the separation between them was varied in order to vary the ratio of electrode area / effluent volume and; for a batch type electrocoagulation reactor in which 27 tests were carried out; keeping the volume of effluent treated constant. From the results obtained, it was determined that the increase in the electrocoagulation time and the electrode area / effluent volume ratio influence the percentage of hexavalent chromium reduction of the artificial chromium plating, as supported by ANOVA and test F; the maximum reduction percentage achieved was 91.65%, with respect to the initial concentration (20 mg/L), for a test time of 60 minutes and a ratio of electrode area / effluent volume of 0.912 m2/L.