A STUDY ON ENHANCING THE FLAME RETARDANCY OF POLYPROPYLENE YARN WITH BORON COMPOUNDS

Functional properties such as; water resistance, flame retardancy, antibacterial efficiency etc. are required from textile products. One of the most commonly demanded products among functional textile products is the flame-retardant textiles. In this study, it is aimed to produce polypropylene filament yarn with permanent flame retardancy functionality by adding boron compound, which is Anhydrous disodium tetraborate powder (particle size < 38 micron), to the fiber structure during melt spinning process. In this study two different yarn samples are produced with anhydrous disodium tetraborate content by mass ratios of 2% and 5%. A control polypropylene filament yarn sample is also produced with no additive. By this way, three samples are produced by a conventional BCF polypropylene melt spinning machine with the same production parameters. Then, three knitted fabric samples were produced flat knitting machine. Limiting Oxygen Index (LOI) and vertical flammability tests were applied to the samples. According to results an important level of increase for LOI value is obtained with the sample which has 2% boron compound additive. Nevertheless, there is not a consistent effect of increasing boron content in yarn structure for LOI value. The reason of this situation may be resulted due to the uneven distribution of the boron compound in the yarn structure because of the particle size.

Ketahanan Gubal Jati Hutan Rakyat Diawetkan dengan Senyawa Boron Menggunakan Metode Tekan Lowry terhadap Serangan Rayap Tanah dan Kayu Kering

Nowadays, most of teak wood that available on the market was mainly from comunity forest. Those teak woods were commonly harvested in the early age. The young teak wood from community forests possesses lower proportion of heartwood than sapwood. Those condition was generally had an affect on the wood durability. Although the wood durability was estimated to be low, but the teak wood from community forest was intensively used for furniture and house construction. Therefore, study on the sapwood durability of young teak wood from community forest is necessary. In the present study, the durability of sapwood treated by boron compound (boric acid and borax) as wood preservatives was investigated. The boron concentrations were 5, 7 and 10%. The vacuum process were used to impreg the preservative into the wood specimens called as Lowry method. The efectivity of preservation method were investigated, namely absorption, retention, penetration, efficacy of subterranean and dry-wood termites. The absorption, retention, and penetration of boron compound were 69.10–96.41 kg/m3, 4.53–5.31 kg/m3, and 3.04–3.16 mm, respectively. Absorption, retention, and penetration of preservatives showed an increasing value by increasing the preservatives concentrations, with the highest values were obtained for 10% boron concentration. Graveyard test was used to evaluate the efficacy of boron in teak sapwood to subterranean termites. During 2 months observation, mass loss and degree of wood damage were 0.42-1.37% and 6.31-18.72%. Furthermore, the efficacy of boron was also conducted for dry-wood termites. The mass loss, degree of wood damage, and dry-wood termites mortality after 28 days observation were 1.46-1.67%, 29.45-32.38%, and 87.33-95.33%, respectively. The durability of boron treatened teak sapwood against subterranean and dry-wood termites was increased. The increasing of teak sapwood durability was characterized by reduction of mass loss and degree of wood damage compared to untreated teak sapwood (control).

The Therapeutic Effects of Dodecaborate Containing Boronophenylalanine for Boron Neutron Capture Therapy in a Rat Brain Tumor Model

Background: The development of effective boron compounds is a major area of research in the study of boron neutron capture therapy (BNCT). We created a novel boron compound, boronophenylalanine–amide alkyl dodecaborate (BADB), for application in BNCT and focused on elucidating how it affected a rat brain tumor model. Methods: The boron concentration of F98 rat glioma cells following exposure to boronophenylalanine (BPA) (which is currently being utilized clinically) and BADB was evaluated, and the biodistributions in F98 glioma-bearing rats were assessed. In neutron irradiation studies, the in vitro cytotoxicity of each boron compound and the in vivo corresponding therapeutic effect were evaluated in terms of survival time. Results: The survival fractions of the groups irradiated with BPA and BADB were not significantly different. BADB administered for 6 h after the termination of convection-enhanced delivery ensured the highest boron concentration in the tumor (45.8 μg B/g). The median survival time in the BADB in combination with BPA group showed a more significant prolongation of survival than that of the BPA group. Conclusion: BADB is a novel boron compound for BNCT that triggers a prolonged survival effect in patients receiving BNCT.

ANODIC PROCESSES DURING ELECTRODEPOSITION OF NICKEL, ITS ALLOYS AND COMPOSITE COATINGS

The results of investigations of the anodic processes of electrodeposition of nickel, nickel-boron alloy, composite coatings nickel-ultrafine diamond and nickel-cobalt-aluminum oxide are presented. It was shown that the oxidation of the boron-containing additive occurs at potentials much more positive than the oxidation potential of nickel, which means that oxidation of the boron compound is impossible under real conditions of electrodeposition. During the electrodeposition of CEC, the anode process proceeds without any complications and the dissolution of the anodes occurs in the same way as in nickel-plating electrolytes, and the composite additives of UDD and Al2O3 do not affect the anodic processes.