Impaction of spray droplets on leaves: influence of formulation and leaf character on shatter, bounce and adhesion

This paper combines experimental data with simple mathematical models to investigate the influence of spray formulation type and leaf character (wettability) on shatter, bounce and adhesion of droplets impacting with cotton, rice and wheat leaves. Impaction criteria that allow for different angles of the leaf surface and the droplet impact trajectory are presented; their predictions are based on whether combinations of droplet size and velocity lie above or below bounce and shatter boundaries. In the experimental component, real leaves are used, with all their inherent natural variability. Further, commercial agricultural spray nozzles are employed, resulting in a range of droplet characteristics. Given this natural variability, there is broad agreement between the data and predictions. As predicted, the shatter of droplets was found to increase as droplet size and velocity increased, and the surface became harder to wet. Bouncing of droplets occurred most frequently on hard to wet surfaces with high surface tension mixtures. On the other hand, a number of small droplets with low impact velocity were observed to bounce when predicted to lie well within the adhering regime. We believe this discrepancy between the predictions and experimental data could be due to air layer effects that were not taken into account in the current bounce equations. Other discrepancies between experiment and theory are thought to be due to the current assumption of a dry impact surface, whereas, in practice, the leaf surfaces became increasingly covered with fluid throughout the spray test runs.Comment: 19 pages, 6 figures, accepted for publication by Experiments in Fluid

Kinetic and mechanistic features on the reaction of stored TiO2 electrons with Hg (II), Pb (II) and Ni (II) in aqueous suspension

The reaction of electrons stored on TiO2 nanoparticles with heavy metal ions Hg (II), Ni (II) and Pb (II) has been studied employing steady state and stopped flow spectrophotometric techniques. Prior to kinetic investigation the formation of metal deposits is detected by their surface Plasmon absorbance observed after mixing of their corresponding metal ions with stored electron on TiO2 nanoparticles (eTiO2-). The dynamic of transfer of stored TiO2 electrons to Hg (II), Pb (II) and Ni (II) in water has been investigated after mixing in the stopped flow chamber following the decrease of the absorbance of eTiO2- at 600nm. The results indicate that Hg (II), Pb (II) and Ni (II) ions react readily with eTiO2-The kinetic parameters of the electron transfer reactions have been obtained by pseudo first order fitting. In the presence of Hg (II) ions, the transients decay followed by a buildup at 380-480nmrange. In the presence of Pb (II) and Ni (II), a concurrent decay of TiO2 electron absorbance and buildup of the absorbance of metal deposits were observed. The rate constants of the electron transfer reactions induced by TiO2 stored electrons to metal ions increase with the driving force of the reaction according to Tafel equation

Beberapa Faktor yang Berhubungan dengan Diakuinya Seseorang sebagai Pemimpin Opini dan Manfaatnya untuk Kegiatan Penyuluhan

Opinion Leader at a certain areas, highly contributes to diffusion and adoption process, and has certain effect to social system whether the farmers rejected or accepted to a innovation. The research identified existence and function of Opinion Leader in an areas and analyzed correlated factors of recognition of Opinion Leader. Respondent were farmers of Floating Net Fish Culture at Coklat Area, Cirata Dam, District of Cianjur, West Java Province. The survey conducted since February until May 2005.The result showed that the farmers population, there were eight persons who considered by the respondents as sources of innovation and opinion. Futhermore internal characteristic had a positive value correlation among factors toward recognition level of Opinion Leader, but external characteristic showed negative correlation. Specially, the function of Opinion Leader those were strong correlation toward recognition farmers level to Opinion Leader

The rectilinear Steiner tree problem with given topology and length restrictions

We consider the problem of embedding the Steiner points of a Steiner tree with given topology into the rectilinear plane. Thereby, the length of the path between a distinguished terminal and each other terminal must not exceed given length restrictions. We want to minimize the total length of the tree. The problem can be formulated as a linear program and therefore it is solvable in polynomial time. In this paper we analyze the structure of feasible embeddings and give a combinatorial polynomial time algorithm for the problem. Our algorithm combines a dynamic programming approach and binary search and relies on the total unimodularity of a matrix appearing in a sub-problem.Comment: 14 page

Effect of Coated Methionine and Lysine and Their Combination on Fertility of Awassi Male Sheep

This study was conducted to determine the effect of Amino acid Methionine and Lysine on the reproductive performance of male Awassi sheep. Twenty Awassi males aged range 10-12 months and average weight 32± 0.5kg were used in this study, during the period from May to August 2022. The animals were randomly divided into four equal groups. The first group was the control group (T1). In this group, sheep were fed on standard diet without any additive. The second treated group (T2) were fed on standard diet supplemented with coated Methionine (1.5g/sheep/day). The third treated group (T3) were fed on standard diet supplemented with coated Lysine (2.5g/sheep/day). The fourth treated group (T4) were fed on standard diet supplemented with coated Methionine and Lysine at the same doses used in T2 and T3 .The results showed that there was a significant improvement (P≤0.05) in sperm characteristics of T4 as compared to other groups. T4 also showed the highest testosterone levels as compared with the other groups.T4group also showed a well development in the seminiferous tubules, Sertoli cells and Leydig cells as compared withT1.T4 showed the best histological testicular architecture especially Sertoli cells as compared with T1,T2andT3. It was concluded from this study that coated Methionine and Lysine might improve semen characteristics, testosterone levels and male reproductive performance in Awassi male

Alcohol Sale Status and Homicide Victimization in Kentucky, 2005-2012: Is There a Spatial Association?

To date, the association between the alcohol sale status of decedents’ residence and alcohol-related homicide victimization have not been studied as far as we know. The current study aims to: i) determine whether homicide victims who were residents of wet counties had higher odds of testing positive for alcohol than their counterparts in moist or dry counties after adjusting for confounders; ii) determine whether homicides and alcohol-related homicides tend to cluster spatially; iii) determine whether the aforementioned associations exist only in highly-populated counties. A multilevel logistic regression analysis was used to analyze the data on homicide victims in the Kentucky Violent Death Reporting System from 2005 to 2012. Spatial statistics were used to determine the spatial autocorrelation in rates of homicides and alcohol-related homicides. Overall, 944 homicide victims were included. The male to female ratio was 3:1. About 32.8% of homicide victims tested positive for alcohol. About 33.0% of homicide decedents who were residents in wet counties tested positive for alcohol compared to 32.5% of their counterparts in moist/dry counties. Residence in wet counties was associated with a statistically insignificant increase in the unadjusted odds ratio (OR) of alcohol-related homicide victimization (OR=1.20, 95% CI=0.81-1.77) as well as the adjusted odds (aOR=1.33, 95% CI=0.83-2.12). There was no association between population size and alcohol-related homicide rate

Spin transport theory in ferromagnet/semiconductor systems with non-collinear magnetization configurations

We present a comprehensive theory of spin transport in a non-degenerate semiconductor that is in contact with multiple ferromagnetic terminals. The spin dynamics in the semiconductor is studied during a perturbation of a general, non-collinear magnetization configuration and a method is shown to identify the various configurations from current signals. The conventional Landauer-B\"{u}ttiker description for spin transport across Schottky contacts is generalized by the use of a non-linearized I-V relation, and it is extended by taking into account non-coherent transport mechanisms. The theory is used to analyze a three terminal lateral structure where a significant difference in the spin accumulation profile is found when comparing the results of this model with the conventional model.Comment: 17 pages, 10 figure

Response of carbon fluxes to water relations in a savanna ecosystem in South Africa

International audienceThe principal mechanisms that connect carbon fluxes with water relations in savanna ecosystems were studied by using eddy covariance in a savanna ecosystem at Kruger National Park, South Africa. Since the annual drought and rewetting cycle is a major factor influencing the function of savanna ecosystems, this work focused on the close inter-connection between water relations and carbon fluxes. Data from a nine-month measuring campaign lasting from the early wet season to the late dry season were used. Total ecosystem respiration showed highest values at the onset of the growing season, a slightly lower plateau during the main part of the growing season and a continuous decrease during the transition towards the dry season. The regulation of canopy conductance was changed in two ways: changes due to phenology during the course of the growing season and short-term acclimation to soil water conditions. The most constant parameter was water use efficiency that was influenced by VPD during the day but the VPD response curve of water usage did change only slightly during the course of the growing season and decreased by about 30% during the transition from wet to dry season. The regulation of canopy conductance and photosynthetic capacity were closely related. This observation meets recent leaf-level findings that stomatal closure triggers down-regulation of Rubisco during drought. Our results may show the effects of these processes on the ecosystem scale

Analisis Tingkat Adopsi Inovasi Teknologi Budidaya Ikan Lele Sangkuriang pada Kelompok Ranca Kembang di Kecamatan Cipanas Kabupaten Lebak

Pengalaman USAha bidang perikanan pada responden berhubungan erat sapai pada pada tahap mencoba inovasi, sedangkan tingkat keinovatifan responden berhubungan erat sampai pada tingkat menerapkan inovasi yang dianjurkan. Umur responden. Lama pendidikan, dan tingkat kekosmopolitan tidak berhubungan erat dengan tingkat adopsi inovasi ikan lele sangkuriang.Peranan penyuluh perikanan sangat berhubungan erat sampai tahap mencoba dan berhubungan erat pada tahap menerapkan para responden terkait inovasi yang dianjurkan yaitu budidaya ikan lele sangkuriang pada kolam terpal. Sedangkan peranan ketua kelompok sangat berhubungnha erat sampai tahap menilai inovasi yang dianjurkan bagi para responden. Peranan dinas perikanan dan peranan media massa kurang berhubungan erat dengan tingkat adopsi budidaya ikan lele sangkuriang pada kolam terpal. Karakteristik inovasi berupa keuntungan relatif budidaya ikan lele sangkuriang dibandingkan inovasi lainnya (budidaya pertanian), keselarasan dengan kondisi lingkungan responden berhubungan sangat erat sampai pada tahap minat responden pada inovasi tersebut. Budidaya ikan lele sangkuriang dianggap tidak rumit diterapkan/dipraktekan oleh responden sangat berhubungan erat bagi responden untuk berminat dan sampai menghitung untung rugi dari inovasi tersebut (tahap minat). Budidaya ikan lele sangkuriang dengan karakteristik yang mudah diamati hasilnya oleh responden berhubungan erat pada tahap minat pada responden dan berhubungan sangat erat pada tahap mencoba. Namun demikian berdasarkan hasil analisis ciri inovasi teknologi budidaya ikan lele sangkuriang pada kolam terpal dengan ciri yang mudah dan cepat diamati yang berhubungan sangat erat kecepatan adopsi sampai tahap mencoba, sedangkan ciri inovasi lainnya baru sampai rata-rata pada tahap mminat