Research on the Tensile Properties of Packaging Film Based on Environmental Protection PVA-KGM

Konjac glucomannan (KGM) and poly (vinyl alcohol) (PVA) were mixed to form gel-like polyelectrolyte solution with glycerol and sorbitol as compound plasticizer, which was used to prepare packaging films via casting and drying. The results show that the tensile strength and elongation at break of the packaging films drop sharply when the blending temperature and blending time exceed 80 °C and 3.5 h. When the mass ratio of sorbitol and glycerol in the compound plasticizer ranges from 1:1 to 1:3, it is beneficial to improve the tensile strength of the packaging films. The microscopic reasons for the change of the tensile properties of the packaging films are mainly caused by diffusion-stop-continuing diffusion—precipitation of low-molecular electrolyte, which makes the system shift from equilibrium-homogeneous state- unbalanced state—heterogeneous state.

Fabrication of C/C–SiC–ZrB2 Ultra-High Temperature Composites through Liquid–Solid Chemical Reaction

In this paper, we aimed to improve the oxidation and ablation resistance of carbon fiber-reinforced carbon (CFC) composites at temperatures above 2000 °C. C/C–SiC–ZrB2 ultra-high temperature ceramic composites were fabricated through a complicated liquid–solid reactive process combining slurry infiltration (SI) and reactive melt infiltration (RMI). A liquid Si–Zr10 eutectic alloy was introduced, at 1600 °C, into porous CFC composites containing two kinds of boride particles (B4C and ZrB2, respectively) to form a SiC–ZrB2 matrix. The effects and mechanism of the introduced B4C and ZrB2 particles on the formation reaction and microstructure of the final C/C–SiC–ZrB2 composites were investigated in detail. It was found that the composite obtained from a C/C–B4C preform displayed a porous and loose structure, and the formed SiC–ZrB2 matrix distributed heterogeneously in the composite due to the asynchronous generation of the SiC and ZrB2 ceramics. However, the C/C–SiC–ZrB2 composite, prepared from a C/C–ZrB2 preform, showed a very dense matrix between the fiber bundles, and elongated plate-like ZrB2 ceramics appeared in the matrix, which were derived from the dissolution–diffusion–precipitation mechanism of the ZrB2 clusters. The latter composite exhibited a relatively higher ZrB2 content (9.51%) and bulk density (2.82 g/cm3), along with lower open porosity (3.43%), which endowed this novel composite with good mechanical properties, including pseudo-plastic fracture behavior.

Diagnosing Disease Of Cow Mastitis And Method Of Using Diffusion-Precipitation Reaction In Agar Gel

The microbial factor is essential in the etiology of mastitis. In this regard, bacteriological diagnostics is one of the decisive moments in the recognition and differentiation of pathological conditions of the mammary gland. However, it takes a lot of time to make a diagnosis using general methods, special culture media and reagents.

ŞEROLOGICAL EVIDENCE OF INFECTIOUS BURSAL DISEASE VIRUS INFECTION IN GREY BREASTED HELMET GUINEA FOWLS (Numida meleagris galeata Pallas) IN AN ARID ZONE OF NIGERIA

A survey of guineafowl sera from Maiduguri area of Borno State for antibody to infectious bursal disease (IBD) virus was carried out between the months of January to April, 1991. Agar gel diffusion precipitation test (AGDT) was the serological method employed for the investigation. Out of the total of 196 sera tested, only 16 were found to contain precipitating antibodies to IBD. This represents 9.1% infection rate.

Interface-mediated formation of basic cobalt carbonate / polyethyleneimine composite microscrolls by strain-induced self-rolling

Polyethyleneimine aids the gas diffusion precipitation of nano-structured basic cobalt carbonate sheets at the air/solution interface. Upon drying, these mineral films undergo self-rolling into 3D coiled structures. Exploring this principle...

Preparation and Electrochemical Properties of Co3O4 Supercapacitor Electrode Materials

A special gas-phase diffusion precipitation method with ammonia as the gas-phase diffusion precipitant was adopted. After fully reacting with different cobalt sources in a sealed space, the liquid funnel was separated and dried, and calcined at different temperatures for 2 h. The prepared Co3O4 powder was used as a supercapacitor (SCs) electrode to measure the electrochemical properties of the prepared material. The influences of different cobalt sources and sodium phosphate monobasic dehydrate on the preparation of Co3O4 SCs electrodes were investigated. The optimal performance of Co3O4 was 640 F·g−1 before modification, and this reached 1140 F·g−1 after modification, which was an improvement of 78.1%.

Degenerate equations in a diffusion–precipitation model for clogging porous media

In this article, we consider diffusive transport of a reactive substance in a saturated porous medium including variable porosity. Thereby, the evolution of the microstructure is caused by precipitation of the transported substance. We are particularly interested in analysing the model when the equations degenerate due to clogging. Introducing an appropriate weighted function space, we are able to handle the degeneracy and obtain analytical results for the transport equation. Also the decay behaviour of this solution with respect to the porosity is investigated. There a restriction on the decay order is assumed, that is, besides low initial concentration also dense precipitation leads to possible high decay. We obtain nonnegativity and boundedness for the weak solution to the transport equation. Moreover, we study an ordinary differential equation (ODE) describing the change of porosity. Thereby, the control of an appropriate weighted norm of the gradient of the porosity is crucial for the analysis of the transport equation. In order to obtain global in time solutions to the overall coupled system, we apply a fixed point argument. The problem is solved for substantially degenerating hydrodynamic parameters.

Показники клітинного метаболізму в сироватці крові коней за латентного перебігу лептоспірозу та ринопневмонії

The article presents the results of research on the parameters of cellular metabolism in 141 horses. Studies were conducted in one of the unsuccessful with leptospirosis equine farm. The kits of the company «Reagent» (Dnipropetrovsk) in blood serum determined the content of such acute phase proteins as ceruloplasmin by the method of Ravin, haptoglobin by reaction with rivanolol, total protein by biuretovoy reaction, albumin by reaction with bromocresol green by methods K.M. Veremeenko et al. (1988). The concentration of nitrites was determined by the interaction of plasma nitrides with the Grice reagent, and the colored complex was colorimetricized using a spectrophotometer at a wavelength of 540 nm using the method of Grand F. et. al. (2001) in the modification of Golikov P.P. (2004). The production and recording of PMA and lysis was carried out in accordance with the «Manual on Laboratory Diagnosis of Leptospirosis» (1997). The reaction of the RDP for the diagnosis of rhinopneumonia of horses was carried out in accordance with the methodological recommendations (2009). The first group (control) was represented by 49 clinically healthy serologically negative in the reaction of microagglutination (PMA) and diffusion precipitation (RDP) reactions with respect to leptospirosis and rhinopneumonia. The second group with latent course of leptospirosis included 51 horses. The third group with latent course of leptospirosis and rhinopneumonia included 41 horses. As a result of our research, we established a significant increase (P < 0.05–0.01) of nitric oxide to 65.73 ± 4.43 and 55.86 ± 2.71 μmol/l in 2–3 groups in comparison with healthy. There is also a significant increase in ceruloplasmin (P < 0.01–0.001) to 216.35 ± 11.43, 243.15 ± 19.34 mg/l in 2–3 groups in comparison with a healthy one. The content of hapthoglobin, on the contrary, decreases to 0.61 ± 0.03 and 0.52 ± 0.04 * g / l in 2–3 groups compared with healthy. Albumin content did not differ significantly in the studied groups. At the same time, a significant reduction of fibrinogen (P < 0.01–0.001) was established to 1.23 ± 0.09 and 1.22 ± 0.08 g/l in 2–3 groups in comparison with healthy ones. The content of soluble fibrin (P < 0.001) to 16.05 ± 0.31 and 21.22 ± 0.71 mg/% in 2–3 groups in comparison with healthy is significantly increased. In a coherent latent course of leptospirosis and rhinopneumonia in horses as markers for assessing the state of immunobiological reactivity of an organism it is advisable to determine the content of nitric oxide, ceruloplasmin, soluble fibrin, fibrinogen and haptoglobin in blood serum. The results obtained are analyzed for the expediency of conducting a course of intensive care for especially valuable horses.