Hydrophobicizing mould release agent for press moulding

2007 ◽  
Vol 59 (5) ◽  
pp. 236-241
Author(s):  
F.T. Seyidov ◽  
Y. Mansoori ◽  
J. Taghi Nezhad
Keyword(s):  
Author(s):  
Shailesh R. Sheth ◽  
Jayesh R. Bellare

Specimen support and astigmatism correction in Electron Microscopy are at least two areas in which lacey polymer films find extensive applications. Although their preparation has been studied for a very long time, present techniques still suffer from incomplete release of the film from its substrate and presence of a large number of pseudo holes in the film. Our method ensures complete removal of the entire lacey film from the substrate and fewer pseudo holes by pre-treating the substrate with Gum Arabic, which acts as a film release agent.The method is based on the classical condensation technique for preparing lacey films which is essentially deposition of minute water or ice droplets on the substrate and laying the polymer film over it, so that micro holes are formed corresponding to the droplets. A microscope glass slide (the substrate) is immersed in 2.0% (w/v) aq. CTAB (cetyl trimethyl ammonium bromide)-0.22% (w/v) aq.


Author(s):  
Sarika Pundir ◽  
Ashutosh Badola

In the present study we have formulated (F1 to F6) matrix tablets of atenolol and indapamide for the management of hypertension. As in simultaneous estimation of these drugs it was found that a confined release can be formulated. In the formulation of SR matrix tablet by using different concentration of delayed release agent DCP and pregelatinized starch as disintegrant we prepared tablets by wet granulation method. For sustained release action HPMC polymers were used for film coating. Preformulation studies were performed prior to compression. The compressed SR matrix tablets were evaluated for weight variation, hardness, friability, drug content, disintegration time and in vitro drug release using USP dissolution apparatus type 2 (paddle). It was found that the optimized formulation showed 49.33%, 48.90%, 48.52%, 47.65%, 46.84% and 46.51% release for atenolol in 12 hours respectively. However, indapamide released 49.62%, 49.39%, 48.72%, 48.27%, 47.59% and 47.36% at the end of 12 hr. The IR spectrum study revealed that there is no disturbance in the principal peaks of pure drugs atenolol and indapamide. This confirms the integrity of pure drugs and no incompatibility of them with excipients. The stability studies were carried out for the optimized batch for one months and it showed satisfactory results. The kinetic studies of the formulations revealed that diffusion is the predominant mechanism of drug and release follows Zero-order, Super case II transport.


2013 ◽  
Vol 35 (3) ◽  
pp. 596-601 ◽  
Author(s):  
Zhengwei Zhou ◽  
Aijun Li ◽  
Ruicheng Bai ◽  
Jinliang Sun

1993 ◽  
Vol 31 (11) ◽  
pp. 825-833 ◽  
Author(s):  
O. Meyer ◽  
E. Kristiansen ◽  
J. Gry ◽  
C. Madsen ◽  
P. Olsen ◽  
...  

2018 ◽  
Vol 37 (2) ◽  
pp. 75-86
Author(s):  
Jamin Saputra

Pemeliharaan tanaman karet melalui pemupukan merupakan salah satu langkah penting yang harus dilakukan untuk mencapai pertumbuhan dan produksi yang optimal. Akhir-akhir ini ketersediaan pupuk yang terbatas, harga yang terus meningkat, dan harga karet yang rendah menyebabkan kegiatan pemupukan pada perkebunan karet sering tertunda. Selain penundaan kegiatan pemupukan juga terjadi pengurangan dosis dan bahkan meniadakan kegiatan pemupukan. Tulisan ini bertujuan untuk mengkaji hasil-hasil penelitian dalam upaya peningkatan efisiensi pemupukan pada tanaman karet sehingga biaya pemupukan dapat dikurangi. Hasil-hasil penelitian sebelumnya menunjukkan bahwa pemupukan dapat dikurangi sampai 75% dari dosis pupuk tunggal apabila menerapkan teknologi pemupukan menggunakan pupuk majemuk dengan tambahan slow release agent yang sering disebut dengan Slow Release Fertilizer (SRF) dan upaya lain dengan menggunakan kombinasi pupuk tunggal dengan pupuk hayati. Selain itu penentuan dosis rekomendasi harus mempertimbangkan sifat tanah sehubungan dengan kapasitas tanah dalam menyediakan unsur hara untuk tanaman, faktor lingkungan yang mempengaruhi efisiensi pemupukan, serta kebutuhan tanaman akan unsur hara sesuai dengan umur, produksi, dan kesehatan tanaman. Pada kondisi pekebun yang mengalami kesulitan melakukan pemupukan akibat harga karet yang rendah maka penundaan pemupukan selama dua tahun belum memberikan efek kerugian finansial bagi pekebun.


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