bluuebunny/crossref_metadata_2025 huggingface dataset:
Investigation of temperature-dependent DC breakdown mechanism of EP/TiO2 nanocomposites
Authors: Li Zhen , Han Yongsen , Liu Ji , Min Daomin , Li Shengtao
Published: August 2022

In dielectric science, the electrical breakdown strength of a polymeric material significantly decreases with elevated temperatures, which restricts the development of advanced electrical and electronic applications toward miniaturization. In the present study, to clarify the temperature-dependent DC breakdown mechanisms of epoxy resin (EP)/TiO2 nanocomposites, the effects of nanoparticle incorporation and temperature on charge transport and molecular chain dynamics were studied. The results indicate that space charge accumulation and electric field distortion are reduced by nanoparticle incorporation to enhance the deep trap level, while space charge accumulation, electric field distortion, and molecular displacement are all accelerated as temperature increases. To further investigate the influence of carrier traps and molecular chain dynamics on temperature-dependent breakdown, a DC breakdown simulation model that involves bipolar charge transport, molecular chain dynamics, and breakdown criterion equations is established. The calculated breakdown strengths of EP/TiO2 nanocomposites show great accordance with the experimental results, which indicates that temperature-dependent DC breakdown mechanisms are dominated by the synergetic effects of carrier traps and segment chain dynamics. Through the analysis of the breakdown model, a transition of the dominant mechanism (from segment chain to backbone dynamics) near the glass-transition temperature for DC breakdown of EP/TiO2 nanocomposites is discovered.
Techniques for second-order convergent weakly compressible smoothed particle hydrodynamics schemes without boundaries
Authors: Negi Pawan , Ramachandran Prabhu
Published: August 2022

Despite the many advances in the use of weakly compressible smoothed particle hydrodynamics (SPH) for the simulation of incompressible fluid flow, it is still challenging to obtain second-order convergence even for simple periodic domains. In this paper, we perform a systematic numerical study of convergence and accuracy of kernel-based approximation, discretization operators, and weakly compressible SPH (WCSPH) schemes. We explore the origins of the errors and issues preventing second-order convergence despite having a periodic domain. Based on the study, we propose several new variations of the basic WCSPH scheme that are all second-order accurate. Additionally, we investigate the linear and angular momentum conservation property of the WCSPH schemes. Our results show that one may construct accurate WCSPH schemes that demonstrate second-order convergence through a judicious choice of kernel, smoothing length, and discretization operators in the discretization of the governing equations.
Augmented transition path theory for sequences of events
Authors: Lorpaiboon Chatipat , Weare Jonathan , Dinner Aaron R.
Published: August 2022

Transition path theory provides a statistical description of the dynamics of a reaction in terms of local spatial quantities. In its original formulation, it is limited to reactions that consist of trajectories flowing from a reactant set A to a product set B. We extend the basic concepts and principles of transition path theory to reactions in which trajectories exhibit a specified sequence of events and illustrate the utility of this generalization on examples.
Development of Fe-based amorphous alloy with high iron content for room-temperature magnetic refrigeration application
Authors: Gao Mengqi , Xie Lei , Li Qiang , Huo Juntao , Chang Chuntao
Published: August 2022

In this work, in order to develop new Fe-based amorphous alloys with room-temperature magnetocaloric effect and good magnetocaloric performance, high iron content Fe-based amorphous alloys were designed, and their Curie temperatures were adjusted to room temperature through the addition of Mo. As a result, a new Fe83Mo6Si1B7P2C1 amorphous alloy with room-temperature magnetocaloric effect was successfully prepared by melt-spinning technique, and it has the Curie temperature of 300 K, the maximum isothermal magnetic entropy change of 2.74 J kg−1 K−1 and the refrigerant capacity of 485.2 J kg−1 under an applied magnetic field of 5 T. Combining with the advantages of excellent magnetocaloric properties, negligible hysteresis loss, and low material cost, the present Fe83Mo6Si1B7P2C1 amorphous alloy should be a promising candidate as room-temperature magnetic refrigerants.
Open-source quality control routine and multi-year power generation data of 175 PV systems
Authors: Visser Lennard R. , Elsinga Boudewijn , AlSkaif Tarek A. , van Sark Wilfried G. J. H. M.
Published: August 2022

In this study, we introduce an open-source dataset holding power measurements of 175 residential photovoltaic (PV) systems that are distributed throughout the province of Utrecht, the Netherlands. The dataset features power measurements with a high temporal resolution, i.e., 1 min, for the period January 2014 until December 2017 (over 260 × 106 data points). Spatial information of the PV systems is mapped through latitude and longitude grids, with a resolution up to 150 × 150 m. In addition, we develop and publish a quality control routine that can be applied to validate and filter PV power measurements. Finally, we propose a method to estimate the rated DC capacity of a PV system based on the power measurements. We have deposited five files into the Zenodo repository [Visser et al. (2022). Zenodo, V. 0.0.1, Dataset https://doi.org/10.5281/zenodo.6906504], which are publicly available. Four numerical datasets are enclosed, holding unfiltered power measurements, filtered power measurements at two different stages and metadata. The latter includes information on the tilt angle, azimuth angle, the estimated DC and AC capacity, and location. Finally, a Python package featuring the quality control routine developed to validate and filter PV power measurements is published.
A polarizable fragment density model and its applications
Authors: Zhang Yingfeng , Qi Ji , Zhou Rui , Yang Minghui
Published: August 2022

This work presented a new model, Polarizable Fragment Density Model (PFDM), for the fast energy estimation of peptides, proteins, or other large molecular systems. By introducing an analogous relation to the virial theorem, the kinetic energy in Kohn–Sham Density Functional Theory (DFT) is approximated to the corresponding potential energy multiplied by a scale factor. Furthermore, the error due to this approximation together with the exchange–correlation energy is approximated as a second order Taylor’s expansion about density. The PFDM energy is expressed as a functional of electronic density with system-dependent model parameters, such as a scaling factor c and a series of atomic pairwise KAB. The electron density in PFDM consists of a frozen part retaining chemical bonding information and a polarizable part to describe polarization effects, both of which are expanded as a linear expansion of Gaussian basis functions. The frozen density can be pre-calculated by fitting the DFT calculated density of fragments, as well as the polarizable density is optimized to solve PFDM energy. The PFDM energy is a quadratic function of the expansion coefficients of polarizable density and can be solved without expensive iteration process and numerical integrals. PFDM is especially suitable for the energy calculation of large molecular system with identical subunits, such as proteins, nucleic acids, and molecular clusters. Applying the PFDM method to the proteins, the results show that the accuracy is comparable to the PM6 semi-empirical method, and the efficiency is one order of magnitude faster than PM6.
Splitting of a three-dimensional liquid plug at an airway bifurcation
Authors: Fujioka Hideki , Romanò Francesco , Muradoglu Metin , Grotberg James B.
Published: August 2022

Employing the moving particles' semi-implicit (MPS) method, this study presents a numerical framework for solving the Navier–Stokes equations for the propagation and the split of a liquid plug through a three-dimensional air-filled bifurcating tube, where the inner surface is coated by a thin fluid film, and surface tension acts on the air–liquid interface. The detailed derivation of a modified MPS method to handle the air–liquid interface of liquid plugs is presented. When the front air–liquid interface of the plug splits at the bifurcation, the interface deforms quickly and causes large wall shear stress. We observe that the presence of a transverse gravitational force causes asymmetries in plug splitting, which becomes more pronounced as the capillary number decreases or the Bond number increases. We also observe that there exists a critical capillary number below which the plug does not split into two daughter tubes but propagates into the lower daughter tube only. In order to deliver the plug into the upper daughter tube, the driving pressure to push the plug is required to overcome the hydrostatic pressure due to gravity. These tendencies agree with our previous experimental and theoretical studies.
Amino acid deprotonation rates from classical force fields
Authors: Lazaridis Themis , Sepehri Aliasghar
Published: August 2022

Acid ionization constants (pKa’s) of titratable amino acid side chains have received a large amount of experimental and theoretical attention. In many situations, however, the rates of protonation and deprotonation, kon and koff, may also be important, for example, in understanding the mechanism of action of proton channels or membrane proteins that couple proton transport to other processes. Protonation and deprotonation involve the making and breaking of covalent bonds, which cannot be studied by classical force fields. However, environment effects on the rates should be captured by such methods. Here, we present an approach for estimating deprotonation rates based on Warshel’s extension of Marcus’s theory of electron transfer, with input from molecular simulations. The missing bond dissociation energy is represented by a constant term determined by fitting the pKa value in solution. The statistics of the energy gap between protonated and deprotonated states is used to compute free energy curves of the two states and, thus, free energy barriers, from which the rate can be deduced. The method is applied to Glu, Asp, and His in bulk solution and select membrane proteins: the M2 proton channel, bacteriorhodopsin, and cytochrome c oxidase.
Phononic quadratic nodal lines of different types in Li2NaN
Authors: Yang Tie , Gu Qijia , Wang Peng , Wu Zhimin , Zhang Zeying
Published: August 2022

The search for new topological states has been shifted from electronic fermionic states to phononic bosonic ones, and topological elements with conventional linear band crossing have also been extended into the high order dispersion field. In this Letter, based on theoretical calculations and effective model analysis, we predicted the quadratic phonon states in the hexagonal compound Li2NaN. Particularly, two quadratic nodal lines are found, which are distributed along the same straight Γ–A path, protected by the C6v point group symmetry. The detailed band surface distribution and effective Hamiltonian construction are elucidated, demonstrating the quadratic order dispersion. These two quadratic nodal lines were further categorized into type-I and type-III, and their surface spectral properties were calculated, in which clear drumhead surface states are observed for both quadratic nodal lines, and they stretched throughout the entire Brillouin zone. Furthermore, the surface states were well separated from the bulk band projection, which is extremely beneficial for experimental detection. Notably, phononic quadratic nodal line states have been rarely studied and, more importantly, a type-III line has even not been reported thus far. Therefore, our work can pave the way for related studies for both quadratic nodal lines and type-III states, and the presented material can serve as an ideal candidate to promote further experimental investigation.
Shot and Johnson noises in interband cascade infrared photodetectors
Authors: Yang Rui Q.
Published: August 2022

Shot and Johnson noises are often incorrectly thought of as two independent noise sources. This incorrect picture has affected the evaluation of detectivities in interband cascade infrared photodetectors (ICIPs). In this work, a unified picture of shot and Johnson noises is developed for ICIPs based on a fundamental framework to understand the origin of Johnson noise and clarify the possible confusion between Johnson and shot noises. General, yet concise expressions are derived to evaluate the current noise power spectral density and detectivity for ICIPs even with complicated structures. Also, simple expressions for the signal current due to absorption of photons and the corresponding photon noise are derived, consistent with the previous results derived from alternative methods. Furthermore, a formula is derived to correctly evaluate the detectivity for conventional photodetectors under a reverse bias. The derived formulas with discussion are expected to improve the understanding of noises in ICIPs and other types of photodetectors and help us to appropriately evaluate their detectivities.
Expanding the absorption and photoresponse of 1D lead–halide perovskites via ultrafast charge transfer
Authors: Chen Zhongwei , Liu Yang , Gong Shaokuan , Zhang Zixuan , Cao Qinxuan , Mao Lingling , Chen Xihan , Lu Haipeng
Published: August 2022

Low-dimensional metal halide perovskites are attracting extensive attention due to their enhanced quantum confinement and stability compared to three-dimensional perovskites. However, low dimensional connectivity in the inorganic frameworks leads to strongly bounded excitons with limited absorption properties, which impedes their application in photovoltaic devices. Here, we show that, by incorporating a strong electron accepting methylviologen cation, charge transfer (CT) at the organic/inorganic interface can effectively tune the optical properties in one-dimensional (1D) lead–halide perovskites. Both 1D MVPb2I6 and MVPb2Br6 display expanded absorption and photoresponse activity compared to CT inactive cations. The photoinduced CT process in MVPb2I6 was further characterized by transient absorption spectroscopy, which shows an ultrafast CT process within 1 ps, generating charge separated states. Our work unveils the interesting photophysics of these unconventional 1D perovskites with functional organic chromophores.
Heterogeneous iodine-organic chemistry fast-tracks marine new particle formation
Authors: Huang Ru-Jin , Hoffmann Thorsten , Ovadnevaite Jurgita , Laaksonen Ari , Kokkola Harri , Xu Wen , Xu Wei , Ceburnis Darius , Zhang Renyi , Seinfeld John H. , O’Dowd Colin
Published: August 2022

The gas-phase formation of new particles less than 1 nm in size and their subsequent growth significantly alters the availability of cloud condensation nuclei (CCN, >30–50 nm), leading to impacts on cloud reflectance and the global radiative budget. However, this growth cannot be accounted for by condensation of typical species driving the initial nucleation. Here, we present evidence that nucleated iodine oxide clusters provide unique sites for the accelerated growth of organic vapors to overcome the coagulation sink. Heterogeneous reactions form low-volatility organic acids and alkylaminium salts in the particle phase, while further oligomerization of small α-dicarbonyls (e.g., glyoxal) drives the particle growth. This identified heterogeneous mechanism explains the occurrence of particle production events at organic vapor concentrations almost an order of magnitude lower than those required for growth via condensation alone. A notable fraction of iodine associated with these growing particles is recycled back into the gas phase, suggesting an effective transport mechanism for iodine to remote regions, acting as a “catalyst” for nucleation and subsequent new particle production in marine air.
Protective anti-gB neutralizing antibodies targeting two vulnerable sites for EBV-cell membrane fusion
Authors: Zhang Xiao , Hong Junping , Zhong Ling , Wu Qian , Zhang Shanshan , Zhu Qianying , Chen Haiwen , Wei Dongmei , Li Rui , Zhang Wanlin , Zhang Xinyu , Wang Guosong , Zhou Xiang , Chen Junyu , Kang Yinfeng , Zha Zhenghui , Duan Xiaobing , Huang Yang , Sun Cong , Kong Xiangwei , Zhou Yan , Chen Yanhong , Ye Xiaoping , Feng Qisheng , Li Shaowei , Xiang Tong , Gao Song , Zeng Mu-Sheng , Zheng Qingbing , Chen Yixin , Zeng Yi-Xin , Xia Ningshao , Xu Miao
Published: August 2022

Epstein-Barr virus (EBV) infects more than 90% of the world’s adult population and accounts for a significant cancer burden of epithelial and B cell origins. Glycoprotein B (gB) is the primary fusogen essential for EBV entry into host cells. Here, we isolated two EBV gB-specific neutralizing antibodies, 3A3 and 3A5; both effectively neutralized the dual-tropic EBV infection of B and epithelial cells. In humanized mice, both antibodies showed effective protection from EBV-induced lymphoproliferative disorders. Cryoelectron microscopy analyses identified that 3A3 and 3A5 bind to nonoverlapping sites on domains D-II and D-IV, respectively. Structure-based mutagenesis revealed that 3A3 and 3A5 inhibit membrane fusion through different mechanisms involving the interference with gB-cell interaction and gB activation. Importantly, the 3A3 and 3A5 epitopes are major targets of protective gB-specific neutralizing antibodies elicited by natural EBV infection in humans, providing potential targets for antiviral therapies and vaccines.
Perspective: New directions in dynamical density functional theory
Authors: te Vrugt Michael , Wittkowski Raphael
Published: August 2022

Classical dynamical density functional theory (DDFT) has become one of the central modeling approaches in nonequilibrium soft matter physics. Recent years have seen the emergence of novel and interesting fields of application for DDFT. In particular, there has been a remarkable growth in the amount of work related to chemistry. Moreover, DDFT has stimulated research on other theories such as phase field crystal models and power functional theory. In this perspective, we summarize the latest developments in the field of DDFT and discuss a variety of possible directions for future research.
fNIRS-based brain state transition features to signify functional degeneration after Parkinson’s disease
Authors: Lu Jiewei , Wang Yue , Shu Zhilin , Zhang Xinyuan , Wang Jin , Cheng Yuanyuan , Zhu Zhizhong , Yu Yang , Wu Jialing , Han Jianda , Yu Ningbo
Published: August 2022

Objective. Parkinson’s disease (PD) is a common neurodegenerative brain disorder, and early diagnosis is of vital importance for treatment. Existing methods are mainly focused on behavior examination, while the functional neurodegeneration after PD has not been well explored. This paper aims to investigate the brain functional variation of PD patients in comparison with healthy controls. Approach. In this work, we propose brain hemodynamic states and state transition features to signify functional degeneration after PD. Firstly, a functional near-infrared spectroscopy (fNIRS)-based experimental paradigm was designed to capture brain activation during dual-task walking from PD patients and healthy controls. Then, three brain states, named expansion, contraction, and intermediate states, were defined with respect to the oxyhemoglobin and deoxyhemoglobin responses. After that, two features were designed from a constructed transition factor and concurrent variations of oxy- and deoxy-hemoglobin over time, to quantify the transitions of brain states. Further, a support vector machine classifier was trained with the proposed features to distinguish PD patients and healthy controls. Main results. Experimental results showed that our method with the proposed brain state transition features achieved classification accuracy of 0.8200 and F score of 0.9091, and outperformed existing fNIRS-based methods. Compared with healthy controls, PD patients had significantly smaller transition acceleration and transition angle. Significance. The proposed brain state transition features well signify functional degeneration of PD patients and may serve as promising functional biomarkers for PD diagnosis.
Nonuniform plasma meniscus modelling based on backward calculation of negative ion beamlet
Authors: Kisaki M. , Nagaoka K. , Slief J.H. , Haba Y. , Nakamoto R. , Tsumori K. , Nakano H. , Ikeda K. , Osakabe M.
Published: August 2022

The shape of a plasma meniscus is a key factor to determine the beam focusing. The physics model of the meniscus formation for hydrogen negative ion sources has not been established yet. A backward trajectory calculation based on experimental observation is performed in order to derive the particle information at the meniscus. It is observed that the negative ion density is spatially nonuniform in the direction parallel to the magnets for suppression of co-extracted electrons. A nonuniformity of the negative ion density in the vicinity of the meniscus is taken into account in the forward trajectory calculation. It reveals that the nonuniform negative ion distribution leads to degradation of the beam focusing and the beam splitting in phase space. The importance of the spatial distribution of negative ions on meniscus modelling is discussed with a comparison to uniform extraction model.
Divergent trends in irrigation-water withdrawal and consumption over mainland China
Authors: Zhang Ling , Zheng Donghai , Zhang Kun , Chen Hao , Ge Yingchun , Li Xin
Published: August 2022

Knowledge of both irrigation-water withdrawal (IWW) and consumption (IWC, i.e. the evapotranspiration loss of applied irrigation water) is critical to sustainable water use and management. However, IWW and IWC are not well differentiated and an integrated analysis of their changes and causes is still lacking. Here we aim to close this gap and investigate the trends and drivers of IWW and IWC over mainland China using the logarithmic mean Divisia index approach and multivariate regression and fixed-effects panel regression models. We find that IWW decreased at a rate of −1.3 km3yr−1 (or −0.4% yr−1) while IWC increased at a rate of 2.9 km3 yr−1 (or 2.4% yr−1) from 1999 to 2013, albeit both showed upward trends from 1982 to 1999. The reduction in IWW was due to the decreased water-withdrawal intensity (WWI) (i.e. IWW per unit area), while the increase in IWC was mainly due to the irrigated area expansion. We find opposite trends in IWW and IWC in about half of the Chinese provinces, with IWW decreasing and IWC increasing in most cases. Changes in irrigation efficiency (IE, defined as the ratio of IWC to IWW) and climatic factors explain a large proportion of the variance in WWI and water-consumption intensity (i.e. IWC per unit area). IE presents a strong negative correlation with WWI but a positive correlation with water-consumption intensity. The improved IE makes a nonnegligible contribution (∼20%) to the irrigated area expansion, especially in water-scarce regions. The strong positive linkage between IE and IWC together with the significant rise in IWC with increasing IE suggest that the paradox of IE (i.e. higher IE tends to increase water consumption) has manifested in mainland China. Our findings highlight the importance of considering both IWW and IWC changes as well as farmer’s behavior adjustments in water resource management.
The role of rebates in public support for carbon taxes
Authors: Fremstad Anders , Mildenberger Matto , Paul Mark , Stadelmann-Steffen Isabelle
Published: August 2022

Economists advocate carbon pricing as the primary tool to reduce greenhouse gas emissions. However, very few governments have adopted a carbon tax high enough to meet international emission targets. Political challenges may stem from a number of areas, including political mobilization by policy opponents, consumers’ willingness to pay and the regressivity of many carbon pricing schemes, which might be addressed through rebates. We use a novel carbon tax calculator to provide residents in the US and Switzerland with personalized estimates of the financial costs and benefits associated with carbon pricing policies. Our results indicate that, absent political messaging, rebates increase public support for carbon taxes in both countries by building support among lower income groups. In the US, we find majority support in our sample for both low ($50/tCO2) and high ($230/tCO2) carbon taxes when rebates are included; in Switzerland public support is lower. However, policy is always politicized, and when respondents are exposed to political messages about carbon pricing the effects associated with rebates are dampened or eliminated.
Climatic limiting factors of North American ecosystems: a remote-sensing based vulnerability analysis
Authors: Sang Zihaohan , Hamann Andreas
Published: August 2022

Remote-sensing based vulnerability assessments to climate change are a research priority of critical importance for landscape-scale efforts to prioritize conservation and management of ecosystems. Limiting climatic factors can serve as a proxy for quantifying ecosystem vulnerability, since theory predicts that ecosystems close to critical climate thresholds will be more sensitive to interannual variation in limiting climate factors. Here, we analyze time series of enhanced vegetation index data for continental-scale vulnerability assessments. The analytical approach is a lagged monthly correlation analysis that accounts for memory effects from the previous growing season. Mapping multivariate correlation coefficients reveals that drought vulnerabilities can be found across the continent, including a distinct geographic band across the western boreal forest. The analytical approach reveals climate dependencies at high spatial and temporal resolution, with the direction and strength of correlation coefficients indicating the risk of threshold transgressions at the edge of species and ecosystem tolerance limits. The approach is further useful for hypothesis testing of contributing non-climatic factors to climatic vulnerability, allowing locally targeted management interventions to address climate change.
Temperate Regenerative Agriculture practices increase soil carbon but not crop yield—a meta-analysis
Authors: Jordon Matthew W , Willis Kathy J , Bürkner Paul-Christian , Haddaway Neal R , Smith Pete , Petrokofsky Gillian
Published: August 2022

Regenerative Agriculture (RA) claims to build soil organic carbon (SOC) and increase crop yields through simultaneous adoption of a suite of management practices which restore soil health. However, this claim is largely unevidenced as few studies of fully integrated regenerative systems are currently available. As a first step to addressing this knowledge gap, we here examine three practices now being promoted as part of RA: reducing tillage intensity, cover cropping and including a grass-based phase in arable rotations (ley-arable rotations). Our Bayesian meta-analysis of 195 paired SOC and crop yield observations from a systematic review of published studies finds statistically significant increases in SOC concentration for reduced tillage intensity (0.06 g C · 100 g−1) and ley-arable rotations (0.05 g C · 100−1 g yr−1 of ley) compared to conventional practice over an average study duration of 15 years, but no effect of cover crops. None of these practices reduce yield during cropping years, although we find no evidence of a win–win between increasing SOC and enhanced agricultural productivity following adoption. Future work should also evaluate the net greenhouse gas emission implications of each practice and potential for synergistic effects if RA practices are adopted in combination. Nevertheless, our results suggest that the RA practices investigated here can be promoted by land managers and policy makers without crop yield losses.
The double barrier problem for Brownian motion with Poissonian resetting
Authors: Villarroel Javier
Published: August 2022

Let a < 0 < b be two fixed points. We consider a diffusive particle in one space dimension whose dynamics combines continuous-time Brownian motion with resetting at random Poisson times. We study the double barrier problem regarding the probability that starting from 0 the Brownian particle escapes (a, b) at the upper barrier b and compare how resetting modifies the exit probabilities. We also study the distribution of the corresponding exit time. We show that the resetting activity may either increase or decrease the meantime to exit a region. A precise condition involving the golden ratio separates both cases. Optimal resetting rates that minimize the mean escape time are considered.
Effects of Conservation and Conventional Tillage on some Soil Hydraulic Properties
Authors: Al-Wazzan Faris A. , Muhammad Sarbast Asaad
Published: August 2022

The aim of the study is to compare the effects of both conservation tillage and conventional tillage on soil physical properties, such as soil water content, soil porosity, bulk density, and soil organic matter. The majority of farmers in Iraq apply conventional tillage for grain production, by using different types plow for land preparation before planting, which increases the cost of production. On the other hand, some farmers use conservation tillage as known as no-tillage system that involves the cultivation without tillage, the only soil disturbance being during the planting time. The research was conducted in Erbil Agriculture Research Directorate for planting bread wheat for three growing seasons (2017 – 2018), (2018 – 2019), (2019-2020) and (2020 – 2021). The land was divided into two parts, the first part was planted with no-tillage tillage, and the second part was planted with conventional tillage by using chisel plow and disk plow before planting. The results indicated that the soil physical properties and soil organic matter were influenced by tillage system. There are no significant differences between both tillage systems on soil moisture content from the sowing time until eight weeks of planting. However, no-tillage system has higher soil moisture content after eight weeks of sowing until flowering stage at 10cm depth. The no-tillage system decreases of soil bulk density and increases soil porosity and soil organic matter compared to conventional tillage system.
Effective of Bacterial Inoculation Azotobacter Chroococcum, Bacillus Subtilis, and Phosphate Rock Fertilizer on Ammonium and Nitrate concentrations in Soil and Plant
Authors: Azzawi Samer Sameer , Kamal Jawad Abdl-Kadhim
Published: August 2022

Aiming to investigate the interaction between Azotobacter Chroococcum, Bacillus Subtilis and four levels of phosphate rock fertilizer 0, 50,100 and 150 kg.K.ha-1 on Ammonium & Nitrate concentrations in Soil and Plant this, field experiment was carried out. The results present that inoculation with Azotobacter Chroococcum, Bacillus Subtilis, and Phosphate Rock Fertilizer singly or double produced a significant increase in (Ammonium concentrations in Soil and Plant and Nitrate concentrations in Soil and Plant) compared to the control. The application of Azotobacter Chroococcum, Bacillus Subtilis, and Phosphate Rock Fertilizer at the level of 150 kg.K.ha-1 (30.75), (3093), (85, 02) (5,917) mg.kg-1. Resulted in the highest values of the studied traits, respectively, compared to the control.
Production and Development of Wind Energy in Wasit and Al-Mothennah Governorates
Authors: Al-Jassani Nisreen Awad , Yasser Al-Najim Aqeel Hassan , Abdel-Mi’mar Howra Najah
Published: August 2022

Renewable or alternative energy is a criterion for international progress in investing its natural resources, especially wind speed. Since the uses of wind are witnessing a wide spread, it has become necessary to work on calculating the rate of wind energy density because it is a criterion that determines the extent to which wind turbines are used or installed. The researcher depends on a comparison between two areas with different classification; where Al-Mothennah governorate enjoys a large quantity of winds, while Wasit governorate is experiencing lower rates than its counterpart in Al-Semawah station.
Practical Study to Find the Best Sound Insulation for Walls From Different Building Materials
Authors: Salih Khalid Ahmed , Khudhur Aktifaa Salih , Abdulla Aziz Ibrahim
Published: August 2022

The sound insulation of walls made of different building materials was tested in various places from Tikrit University in Iraq, with a number of up to 14 walls, distributed in the Department of Environmental Engineering, the Department of Civil Engineering and Chemical Engineering, the Deanship of the College of Arts, the College of Education, the College of Arts, the Department of Psychology, and the Deanship of the College of Computer. It was found through the results that the highest value of sound insulation was obtained for the wall of sequence 13, which amounted to 44.86 dB, but it is for a wall built of thermiston material, and this indicates that thermiston gave the greatest value for sound insulation. The study showed that there are building materials for other walls that can give excellent sound insulation, which is a material republican bricks covered with wood and walls built of sandwich material with a thickness of 10 cm and walls concrete coated with PVC, as well as sandwich walls with a thickness of 7 cm, reaching. The highest values for the rest of the sound insulation results for the top five values were (38.6, 38.43, 37.13, 34, 33.76) dB decibel. The results showed that the perforated brick is no doubt excellent sound insulation and proof of that all the walls built of perforated bricks provided insulation Excellent sound with the rest of the additional isolators used. The study also showed that for the walls of the sandwich panels, with the increase in thickness, the value of sound insulation increases. Where the value of sound insulation (38.43 dB, 34 dB and 30.36 dB) for walls with thickness (10cm, 7cm and 5cm) respectively. Finally, it is important to mention that the lowest value of the measured sound insulation for measured walls was 23.23 decibels, but for a brick wall from the outside of the squirt spreading cement and from the inside with plaster and borax in the College of Engineering - Department of Environmental Engineering building.
Effect of Silica, Bio-Organic Fertilizers, and Spraying of Nano-Titanium and Nano-Cobalt on the Growth and Yield of Rice
Authors: Neamah AL-Sultanei Ameer Eamad , Attia Al-Juthery Hayyawi Wewa
Published: August 2022

In order to evaluate the response of rice plant (Anber 33 cultivar) to fertilization with silica, bio-organic fertilizers and spraying nano-titanium and nano-cobalt on some growth indicators and the yield of rice crop Anber 33 cultivar, The field study was conducted in Al-Tali’a district (boycott 41 - Al-Hussainiya) Babylon province, Iraq. for the period from 15/6/2021 to 23/11/2021.The experiment was conducted according to a randomized complete block design (RCBD).The treatments were randomly distributed according to a simple one-way experiment, where silica fertilizer was added to the treatments at two levels (0 and 300 kg ha-1), as well as the bio-organic fertilizer was added to the treatments at two levels (0 and 1000 kg ha-1).While the treatments of spraying with nanomaterial’s represented by spraying nano-titanium and nano-cobalt and dual sprays of nanomaterials with concentration of 100 mg L-1 each, so the number of treatments was 16 treatments and three replicates. The results of the statistical analysis of Duncan’s test showed that the combined effect of (silica fertilizer + nano-cobalt spray + nano-titanium) recorded the highest results in plant height (122.0) cm, chlorophyll index (40.97) SPAD, and Netting percentage (70.20)%, as well as fertilization (silica and nano-titanium spray). The highest increase in biological yield was recorded (16.25) Mg ha-1, The treatment (silica + bio-organic fertilization + doul spraying of nano-materials) recorded the highest grain yield (4.43) Mg ha-1 and the harvest index (29.69)%, and the weight of 1000 grains (20.90) g. The nano-cobalt spray recorded the highest agronomic efficiency (4270.8) kg kg-1.
Effect of NPK, NPK Organic Fertilizers and Spraying Nano-Vanadium and Nano-Selenium on the Growth and Yield of Rice
Authors: Kadhim Al-Karaawi Mohammed Dayikh , Attia Al-Juthery Hayyawi Wewa
Published: August 2022

The research aims to evaluate the response of rice plant to fertilization with NPK, NPK Organic fertilizers and spraying of nano-vanadium and nano-selenium in some growth and yield indicators of rice (Anber 33 cultivar).A field study was conducted in Al-Tali’a district (41 - Al-Hussainiya, south of Hilla city) Babylon province Iraq, for the period from 15/6/2021 to 26/11/2021.The experiment was conducted according to a randomized complete block design (RCBD).The treatments were randomly distributed according to a simple one-way experiment. The experiment was applied by adding NPK fertilizer at two levels (0 and 300 kg ha-1) and NPK Amino Humic Compound fertilizer at two levels (0 and 1000 kg ha-1).While the treatments of spraying with nanomaterials represented by spraying nano-vanadium and nano-selenium at a concentration (100 mg L-1) were two sprays, bringing the number of experimental units to 16 treatments. The results of the statistical analysis of Duncan’s test showed that fertilizing with organic acids fertilizer with nanomaterials gave the highest plant height, reaching (120 cm). While the combination (NPK+NPKOrganic+nano-vanadium) showed the highest chlorophyll index, which amounted to (40.80) SPAD. While quadruple combination treatment of (NPK+NPKOrganic +nano-vanadium+nano-selenium) achieved the highest values in biological yield (15.93 Mg.ha-1) and grain yield (4.30 Mg.ha-1) and harvest index (27.0%) Also, the single (NPK) treatment gave the highest weight of 1000 grains, which weighed (21.37 g).The spraying of nano-selenium and vanadium recorded the highest agronomic efficiency, reaching (1676.7 and 1468.7 kg kg-1) to spray nano-Va and nano-Se respectively, followed by the dual- combination of nano-materials, which amounted to (1202.7) kg kg-1.
Effect of Spraying Some Nano-Fertilizers and Their Combinations on the Growth and Yield of Fenugreek (Trigonella foenum-graecum L.)
Authors: Nashi Al-Saidi Amal Abdul-Razzaq , Al-Mohammad Maher H.S. , Al-Juthery Hayyawi W. A.
Published: August 2022

The experiment was conducted in one of the special fields for the winter agricultural season 2020/2021 in Al-Qadisiyah province / Sumer-Al-Barakat sub-district, which is 17 km from the district, at 32.14 degrees north latitude and 44.99 degrees east longitude. To know the effect of spraying some nano-fertilizers and their combinations on the growth and yield of the fenugreek, the experiment was carried out according to a randomized complete block design with three replications. The experiment included 10 treatments (T1), the control treatment, spraying distilled water only, (T2) a balanced nano-NPK spraying at a concentration of 2 g L-1, (T3) adding NPK mineral fertilizer 200 kg ha-1, (T4) Spraying nano microelements 2 g L-1 + NPK mineral fertilizer, (T5) Spraying nano seaweed extract 2ml.L-1 + adding NPK mineral fertilizer, (T6) spraying nano NPK at a concentration of 2 g.L-1 + mineral NPK, (T7) Spraying nano micro-elements fertilizer at a concentration of 2 g L-1 + nano seaweed extract at a concentration of 2 ml L-1 + adding NPK mineral fertilizer, (T8) spraying nano micro-elements at a concentration of 2 g L-1 + nano NPK at a concentration of 2 g L-1 + adding NPK mineral fertilizer and (T9) spraying nano seaweed extract at a concentration of 2 ml L-1 + nano NPK at a concentration of 2 g L-1 + adding Mineral NPK fertilizer and (T10) spraying nano-micro elements 2 g. L-1 + nano seaweed extract 2 ml L-1 + NPK nano-concentration 2 g L-1 + adding NPK mineral fertilizer, the first spraying was done three times when the plants reached 6-8 leaves, the second and the third with an interval of 14 days between them. The results showed significantly excelled of plants treated with (T10) and the highest averages were achieved in the vegetative growth traits compared to the control treatment. It also produced the highest averages in all yield traits and its components, especially the fresh and dry leaf yield, and seed and oil yield, which amounted to 12.771, 1.442, 1.431, and 159.48 kg ha-1, respectively, compared with the control treatment, which produced 9.514, 1.163, 1.024 and 99.38 kg ha-1, respectively.
Effect of Chemical, Bio-Fertilizers and Jasmonic Acid and Their Interaction on the Quantitative, Qualitative Characteristics of Olive Fruits Olea europaea L. Cultivar Surani
Authors: Ameen A. J. , Al-Hamdani Kh. A. S.
Published: August 2022

The experiment was carried out in one of the orchards of Laylan district, 19 km from the center of Kirkuk city during the growing season 2021-2022 to study the effect of levels of chemical, bio-fertilizers and jasmonic acid on the fruiting characteristics and yield of olive trees Olea europaea L variety Sorani. Homogeneous vegetative growth, planted on 4 x 4 m lines and irrigated with well water in a drip irrigation system. Trees were sprayed with chemical fertilizers at three levels of 0, 3, 6 ml.L-1 and bio-fertilizers were added at three levels of 0, 20, 40 g.L-1. Trees were also sprayed with jasmonic acid at three levels: 0, 20, and 30 mg.L-1, at an average of 21 days between one spray and another. The experiment was designed according to a randomized complete block design (RCBD), The study reached the following results :- Spraying with chemical fertilizers, especially at the level of 6 ml L-1 (M2), led to a significant increase in studied characteristics, represented in the yield rate for one tree, fruit weight, fruit volume, pulp thickness, T.S.S, and Fruit oil percentage, which reached 21.97 kg.Tree-1, 1.72 g. Fruit -1, 1.77 cm3, 2.14 mm, 17.27%, 16.95% respectively, while the comparison treatment gave the lowest average for the aforementioned traits. Addition of bio-fertilizer, especially the level of 40 gm L-1 (B2), led to a significant increase in the studied characteristics, which are the yield rate per tree, fruit weight, fruit volume, pulp thickness, T.S.S and fruit oil percentage, which reached 21.90 kg.tree-1, 1.79 g.fruit -1, 1.81 cm3, 2.22 mm, 17.37%, 17.11% respectively, while the comparison treatment gave the lowest average for the aforementioned traits. Also, spraying with jasmonic acid at a level of 30 mg L-1 (J2) significantly increased yield per tree, fruit weight, fruit volume, pulp thickness, T.S.S and fruit oil percentage, which reached 21.26 kg.tree-1,1.64 g.fruit-1, 1.66 cm3, 1.96 mm, 16.90%, 16.57% respectively, while the comparison treatment gave the lowest average for the aforementioned traits. There was also a significant increase in the binary and triple interactions of the study treatments on all the studied traits, especially the high levels of the study factors.
Effect of Foliar Spraying with Chelated Iron (CHI) and Dry Yeast Extract (DYE) on Vegetative Growth and Yield Properties of Ashrassi Cultivar Olive Trees
Authors: Hamou Al-Rawi Rasha Hussein , Al-Dulaimi R. M. H.
Published: August 2022

This study was carried out in a private olive field located in the western desert of Rawa city, the village of (Abu Koi) in Anbar Governorate in Iraq during the season 2021-2022 to study the effect of foliar spraying with chelated iron (CHI) At three levels of concentrations (0, 100, and 200 mg L-1) have symbols of (F0, F1, and F2) respectively as well as dry yeast extract (DYE) (Y0, Y1, and Y2) With three concentration levels (0, 10, 20 g L-1) respectively, and their interactions. To investigate their effect on the properties of vegetative and fruitful growth of Ashrassi cultivar olive. Trees were sprayed until full wetness three consecutive times. The first spray was in April after full bloom, the second was in May and the last spray was in June. The results showed that the effect of foliar spraying with CHI for the treatment F2 At a concentration of 200 mg per tree has significant differences in the increase in the number of leaves, as it reached 77.75 leaves per plant. The increase in the length of the branch was 90.97 cm per plant; the leaf area was 7.20 cm2 per plant. The percentage of the dry matter of the fruits was 50.88 %, the weight of the fruit reached 6.38 g per plant, the oil percentage per pant was 17.41%, as well as an increase in iron concentration in the leaves which reached 31.63 mg per kg. Whereas the treatment F1of 100 mg L-1 showed a significant difference in the number of hermaphrodite flowers, which amounted to 11.25 flowers per inflorescences, the percentage of carbohydrates in the leaves was 5.29%, and the percentage of dry matter in the fruits was 48.80%. Furthermore, the effect of foliar application with the second factor (dry yeast suspension) illustrated significant superiority of Y2 treatment (20 g L-1) for the length of the branch where it reaches 84.25 cm per tree, leaf area 7.05 cm2, the number of hermaphrodite flowers 10.93 flowers per inflorescences, the weight of whole fruit was 6.38 g, the increase of fruit diameter was 21.95 mm, the percentage of carbohydrates in the leaves is 6.03 %, the percentage of the dry matter of the fruits was 53.53%, and the percentage of pureness of the pulp of the fruit 88.28%, and the iron concentration in the leaves reached 24.40 mg. kg-1. As for the treatment Y1 at a concentration of 10 gm L-1. It showed significant differences in the diameter of the fruit amounted to 21.74 mm, the weight of the fruit was 6.10 g, the percentage of dry matter of the fruits was 50.74 %, and the percentage of oil in the fruits was 16.34 %.
Effect of Foliar Application with Potassium Sulphate and Organic Fertilizer on Growth Parameters and Yield of Brussels Sprouts “Brassica oleracea L. var. gemmiferaZenk”
Authors: Ali Sarmad Salim , Manea Ali Ibadi , Kshash BassimHaleem
Published: August 2022

This experiment place was done at Babylon territory, Iraq, during 2021-2022 to concentrate on the impact of potassium sulfate (0 and 3 gm.L-1) and natural manure (3 Mt. ha-1 Imported poultry manure (Caspian), 5.7 Mt·ha-1domestic poultry compost, and 6.3 Mt·ha-1 Feather poultry residuals on development growth and yield of Brussels sprouts. The experiment was organized in a split-plot system with a randomized completeblock design with Potassium sulfate as the main plot and organic manure treatment as the sub-plot and with three replications. The results show of the concetration 3 gm.L-1 potassium sulfatesignificant succeeded in plant height 39.33 cm, number of leaves 28.20 leaf per plant, percent dry matter in heads 20.06%, head diameter 2.26 cm, total chlorophyll 23.77 mg. 100 gm fresh weight, percent of nitrogen and potassium 2.07%, 1.87% and vitamin c 74.4 mg. 100 gm fresh weight. Feather poultry residuals also gave the highest average of the head weight 4.8 gm., head diameter 2.20 cm, plant yield 70.9 gm, percent of nitrogen and potassium 1.98%, 1.79% and vitamin c 69.5 mg. 100 gm. fresh weight. The treatment of bi- interaction between concentration potassium sulfate 3 gm. L-1 + feather poultry residuals excelled in the average head weight, total chlorophyll, plant yield. total yield, percent of nitrogen and potassium and vitamin c content. while bi- interaction between concentration potassium sulfate 3 gm. L-1 + imported poultry manure excelled in the average number of leaves, percent dry matter and head diameter.