The Effects of Formulation on Imidacloprid Dissipation in Grapes and Vine Leaves and on Required Pre-Harvest Intervals under Lebanese Climatic Conditions

In this study, imidacloprid, a systemic insecticide, currently having a specified European Commission MRL value for vine leaves (2 mg kg−1), was applied on a Lebanese vineyard under different commercial formulations: as a soluble liquid (SL) and water dispersible granules (WDG). In Lebanon, many commercial formulations of imidacloprid are subject to the same critical good agricultural practice (cGAP). It was, therefore, important to verify the variability in dissipation patterns according to matrix nature and formulation type. Random samplings of grapes and vine leaves were performed starting at 2 days until 18 days after treatment. Residue extractions were performed according to the QuEChERS method and the analytical determination using liquid chromatography coupled to tandem mass spectrometry (LC-MS-MS). The SL formulation yielded significantly higher initial deposit than the WDG formulation on grapes and vine leaves. The formulation type did not significantly affect the dissipation rates; the estimated half-lives in grapes and vine leaves were 0.5 days for all imidacloprid formulations. No pre-harvest intervals were necessary on grapes. PHIs of 3.7 days for the SL formulation and 2.8 days for the WDG formulation were estimated on vine leaves. The results showed that the type of formulation and the morphological and physiological characteristics of the matrix had an effect on the initial deposits, and thus residue levels, but not on the dissipation patterns.

A Short Review on Application of Liquisolid Technology

In this paper we have surveyed about formulation and evaluation of Liquisolid formulations and its work in antidiabetics . Mostly poorly water soluble drugs are in research category despite of less dissolution rate and poor bioavailability. Solubility is a vital parameter to develop new formulation as industries faced serious issue regarding the poor aqueous solubility of the drugs. Various methods for solubility enhancement include modifications of the drug, involvement of co-solvents, complexation, salt formation, size reduction. A propitious technique to solve major challenges like solubility, dissolution rate and their bioavailability. This technique can be defined as the conversion of poorly soluble liquid medications into non-adherent, dry, compressible and free flowing powder mixtures with help of excipients. Many anti-diabetic drugs are belonging to BCS Class-II facing challenges like solubility and bioavailability.

Selection, Sizing, and Modeling of a Trickle Bed Reactor to Produce 1,2 Propanediol from Biodiesel Glycerol Residue

Propylene glycol, also known as 1,2 propanediol, is one of the most important chemicals in the industry. It is a water-soluble liquid, considered by the U.S. Food and Drug Administration as safe to manufacture consumer products, including foodstuffs, medicines, and cosmetics. This chemical has essential properties, such as solvent, moisturizer, or antifreeze, in addition to a low level of toxicity. This paper aims to present the selection, simulation, and dimensioning of a trickle bed reactor at a laboratory scale. The sizing was validated with other authors. Two predictive models have been considered for reactor modeling, intrinsic kinetics and coupled intrinsic kinetics, along with mass transfer equations and the wetting of the catalyst particles. The model was implemented using Aspen Custom Modeler® (20 Crosby Dr. Bedford, MA 01730, EE. UU.) to study the reactor behavior in terms of conversion. The results show the profiles of different variables throughout the reactor and present higher glycerol conversion when mass transfer is added to the model.

Peningkatan hasil dan penekanan kejadian penyakit pada jagung manis (Zea mays var. Bonanza) dengan pemanfaatan biostimulan berbahan kitosan

Corn, an important crop in Indonesia still has a low productivity, thus many efforts are required to fulfill its national demand. One of the solutions to improve corn yield is by applying biostimulant containing chitosan as an active ingredient. Chitosan has been proved to increase plant growth and resistance against diseases. The objective of this research was to study the effects of several chitosan formulas on the yield and diseases occurance in sweet corn (Zea mays var. Bonanza). The chitosan formulas tested were soluble liquid(SL), wettable powder (WP), nano chitosan (NN), and unformulated chitosan (CH). The experiment was arranged using a randomized block design with three replications. All chitosan formulas were applied by seeds soaking for 20 minutes, followed by foliar spraying on corn plants at three weeks after planting (WAP), with the concentration of 500 ppm (400 L/ha spray volume), every threeweeks until 9 WAP. Parameters observed were brix value, weight of corn cobs, weight of corn biomass, and plant diseases including downy leaves, leafblight and leaf rust. The results showed that NN formula increased the brix value up to 7%, the corn cob weight up to 49% and the biomass weight upto 34% compared to the control; whereas SL formula reduced the incidence of downy mildew by 53% at 3 WAP and leaf blight disease by 51% at 6 WAP. In addition, the incidence of corn leaf rust reduced 59-71% in corn plant subjected to all chitosan formulas. Based on the results, application of chitosan in NN formula was best in increasing yield, while in SL formula was best in reducing the incidence of important corn diseases.[Keywords: downy mildew, chitosan formula, seed treatment]AbstrakJagung sebagai salah satu komoditas pangan penting di Indonesia masih memiliki produktivitas yang rendah sehingga diperlukan usaha untuk memenuhi kebutuhan jagung nasional. Salah satu cara untuk meningkatkan hasil jagung adalah dengan aplikasi biostimulan yang mengandung bahan aktif kitosan. Kitosan telah terbukti mampu meningkatkan pertumbuhan dan daya tahantanaman terhadap penyakit. Penelitian ini bertujuan mempelajari pengaruh beberapa formula kitosan terhadap hasil dan kejadian penyakit pada tanaman jagung manis (Zea mays var. Bonanza). Formula kitosan yang diuji adalah cairan yang dapat larut (soluble liquid, SL), tepung yang dapat dibasahi (wettable powder, WP), nano kitosan (nano chitosan, NN), dan kitosan non formulasi (unformulated chitosan, CH). Percobaan dilakukan menggunakan rancangan acak kelompok (RAK) dengan tiga ulangan. Masingmasing formula kitosan tersebut diaplikasikan melalui perendaman benih selama 20 menit yangdiikuti dengan penyemprotan daun pada tanaman jagung berumur tiga minggu dengan konsentrasi 500 ppm (volume semprot 400 L/ha) yang dilakukan setiap tiga minggu sampai tanaman berumur sembilan minggu. Parameter yangdiamati adalah nilai brix, bobot tongkol jagung, bobot biomassa jagung, dan penekanan kejadian beberapa penyakit tanaman meliputi bulai, hawardaun, dan karat daun. Hasil penelitian menunjukkan bahwa aplikasi kitosan NNmeningkatkan nilai brix jagung manis hingga 7%, bobot tongkol jagung hingga 49% dan bobot biomassa hingga 34% dibandingkan dengan kontrol. Sementara itu, aplikasi kitosan SL dapat menekan kejadian penyakit bulai hingga 53% padaumur tanaman 3 minggu setelah tanam (MST) dan penyakit hawar daun hingga 51% pada umur 6 MST. Selain itu, kejadian penyakit karat daun jagung juga dapat ditekan 59-71% pada aplikasi keempat formula kitosan. Berdasarkan hasiltersebut, aplikasi kitosan NN paling optimal dalam meningkatkan hasil panen jagung manis, sedangkan aplikasi kitosan SL paling optimal dalam menekan kejadian beberapa penyakit pada tanaman jagung.[Kata Kunci: bulai, formula kitosan, perlakuan benih]

Synthesis and Properties of an N-Substituted Polypyrrole with Liquid Crystalline Moieties

The synthesis and characterisation of two pyrrole monomers substituted at the N-position with a liquid crystal group are reported. Polymerisation of one of these compounds produced a soluble liquid crystalline semiconducting polymer. The side-chain of the polymer had a flexible spacer of nine methylene units, terminated by a mesogenic cyanobiphenyl group. The new compounds were chemically characterised and were found by hot-stage polarised optical microscopy to exhibit liquid crystal mesophases. The polymer was lightly doped p-type by exposure to iodine vapour, and its electrical conductivity was measured. The polymer synthesis and doping/dedoping processes were also briefly studied by cyclic voltammetry.

Segregation in dissolving binary-component sessile droplets

The dissolution of a single droplet, containing a mixture of oils, in water is experimentally studied. The oils in the droplet varied in terms of their solubility in water and their hydrophobicity. We demonstrate that the polarity of the droplet constituents strongly influences the dissolution dynamics. A binary-component droplet, containing two polar components (one soluble the other insoluble) exhibits a retarded dissolution as compared to a droplet containing only the soluble component. We argue that in this case the mixture in the droplet can be assumed homogeneous, leading to a smaller effective contact area of the soluble liquid in the droplet with the bulk water, and thus delayed dissolution. On the other hand, it is shown that this is not the case when a polar, soluble component is mixed with an insoluble non-polar component, in which case segregation between the different liquids inside the droplet occurs, leading to Marangoni flows and superspreading of the droplet. The segregation is confirmed by volumetric measurements and by the use of a solvatochromic dye in combination with confocal microscopy, which clearly showed that during dissolution local concentration differences inside the droplet developed.

Influence of Application Method and Chemical Form on the Absorption and Translocation of Aminocyclopyrachlor in Black Walnut

Absorption and translocation of aminocyclopyrachlor (AMCP) was investigated in black walnut. Radiolabeled AMCP was applied foliarly as a free acid, and basally as a free-acid-formulated oil-soluble liquid and as a methyl ester emusifiable concentrate. Maximum absorption was 68% for the methyl ester, 47% for the free-acid oil-soluble liquid, and 8% for the free acid when evaluated as percent applied. When recovered AMCP was presented as Bq g−1, no difference was observed in AMCP absorption or translocation of 14C-labeled material out of treated plant parts. Recovery of applied radiolabeled material in the roots from basal applications was 5 to 11% 72 h after treatment (HAT), compared with 0.8% recovery from a foliar application. Regardless of chemical form or formulation type, comparable injury was observed within 72 HAT despite low levels of translocation.