Hasil Pencarian  ::  Simpan CSV :: Kembali

"In this work mixing rule of sanches - lacombe equation of state (SL-Eos) was developed for estimating vapor-liquid equilibria of solvent-polymer systems or solubility of solvent in polymer solutions....."

"Pada penelitian ini, Ion Imprinted Polymer (IIP) disintesis dengan metode polimerisasi bulk berbasis Ultrasonic Assisted Dispersive untuk ekstraksinya dengan asam galat sebagai monomer fungsional dan logam Cd²⁺ sebagai template. Hasil karakterisasi FTIR dan SEM-EDX menunjukkan keberhasilan terbentuknya produk Cd(II)-IIP serta terbentuknya rongga spesifik dari Cd(II)-IIP. TGA menujukkan tiga dekomposisi termal dari Cd(II)-IIP dan NIP. Uji adsorpsi menunjukkan bahwa perbandingan sintesis yang optimal dihasilkan pada rasio perbandingan ligan:monomer 1:1 dengan kapasitas adsorpsi 159,038 mg/g pada pH 7 dan waktu kontak 90 menit. Persamaan regresi dari Cd(II)-IIP Ultrasonic Assisted Dispersive mengikuti model isoterm Freundlich dengan . Hasil penelitian menunjukkan selektivitas yang baik terhadap interferensi logam Zn(II), Fe(III), Cr(III), Cu(II), dan Pb(II) dengan koefisien selektivitas >1. Penggunaan Cd(II)-IIP memiliki repeatabilitas yang baik dengan nilai CV Horwitz sebesar 1,39% dan %RSD yaitu 1,11%. Kemampuan recovery Cd(II)-IIP diuji dengan menggunakan sampel saluran Mookervart dan didapatkan %recovery sebesar 101,88%, 102,02%, dan 102,16%.

---

In this study, Ion Imprinted Polymer (IIP) was synthesized by bulk polymerization method based on Ultrasonic Assisted Dispersive for its extraction with gallic acid as functional monomer and Cd2+ metal as template. The results of FTIR and SEM-EDX characterization showed the successful formation of Cd(II)-IIP products and the formation of specific cavities of Cd(II)-IIP. TGA shows three thermal decompositions of Cd(II)-IIP and NIP. The adsorption test showed that the optimal synthesis ratio was obtained at a 1:1 ligand:monomer ratio with an adsorption capacity of 159.038 mg/g at pH 7 and a contact time of 90 minutes. The regression equation of Cd(II)-IIP Ultrasonic Assisted Dispersive followed the Freundlich isotherm model with R^2=0.9964. The results showed good selectivity against metal interference Zn(II), Fe(III), Cr(III), Cu(II), and Pb(II) with selectivity coefficient >1. The use of Cd(II)-IIP has good repeatability with CV Horwitz value of 1.39% and %RSD of 1.11%. The recovery ability of Cd(II)-IIP was tested using a Mookervart channel sample and obtained %recovery of 101.88%, 102.02%, and 102.16%."

"Penelitian ini merupakan penelitian prospektif dan dilakukan untuk mengetahui apakah terdapat perbedaan antara pemberian 1000 cc larutan Ringer laktat (RL) dengan 500 cc larutan Starch (HAES) 6% terhadap perubahan tekanan darah maternal dan nilai Apgar neonatus pada anestesia bedah sesar. Pada penelitian ini dipilih dengan cara random 40 wanita hamil aterm dengan status fisik ASA kelas I - II yang akan menjalani bedah sesar berencana dengan anestesia subarakhnoid. Ke 40 pasien ini terbagi dalam dua kelompok. Kelompok I akan menerima 1000 cc larutan RL dan kelompok II akan menerima 500 cc larutan HAES 6% sebagai larutan pengisian awal sebelum tindakan anestesia subarakhnoid. Perubahan tekanan darah maternal dalam penelitian ini adalah terjadinya hipotensi yang didefinisikan sebagai penurunan tekanan darah sistolik dibawah 100 mmHg Hipotensi terjadi 50% pada kelompok yang mendapat 1000 cc larutan RL sementara pada kelompok II yang menerima 500 cc larutan HAES 6% hipotensi terjadi 25% penderita. Namun pada uji statistik ternyata perbedaan tersebut tidak bermakna (p>0,05). Sementara itu nilai apgar menit 1 dan 5 pada ke 40 neonatus tidak menunjukkan perbedaan bermakna secara statistik (p>0,05). Dapat disimpulkan bahwa penurunan tekanan darah maternal dan nilai Apgar neonatus menit pertama dan ke lima pada penggunanaan 1000 cc larutan RL sebagai larutan pengisian awal sebelum anestesia subarakhnoid pada bedah sesar tidak menunjukkan perbedaan yang bermakna secara statistik (p>0,05) di bandingkan dengan 500 cc larutan HAES 6%. Hal ini berarti penggunaan 1000 cc larutan RL sebagai larutan pengisian awal sebelum tindakan anestesia subarakhnoid masih dapat digunakan untuk mencegah penurunan tekanan darah maternal.

---

This study was a prospective study and was conducted to determine whether there was a difference between administering 1000 cc of Ringer's lactate (RL) solution and 500 cc of 6% Starch solution (HAES) on changes in maternal blood pressure and neonatal Apgar scores during cesarean section anesthesia. In this study, 40 term pregnant women with ASA class I - II physical status were randomly selected who would undergo planned caesarean section with subarachnoid anesthesia. These 40 patients were divided into two groups. Group I will receive 1000 cc of RL solution and group II will receive 500 cc of 6% HAES solution as an initial filling solution before subarachnoid anesthesia. The change in maternal blood pressure in this study was hypotension which was defined as a decrease in systolic blood pressure below 100 mmHg. Hypotension occurred in 50% of the group that received 1000 cc of RL solution, while in group II which received 500 cc of 6% HAES solution, hypotension occurred in 25% of patients. However, in statistical tests it turned out that the difference was not significant (p>0.05). Meanwhile, Apgar scores at 1 and 5 minutes in the 40 neonates did not show a statistically significant difference (p>0.05). It can be concluded that the reduction in maternal blood pressure and the first and fifth minute Apgar scores of neonates when using 1000 cc of RL solution as an initial filling solution before subarachnoid anesthesia for caesarean section does not show a statistically significant difference (p>0.05) compared with 500 cc of 6% HAES solution. This means that the use of 1000 cc of RL solution as an initial filling solution before subarachnoid anesthesia can still be used to prevent a decrease in maternal blood pressure."

"Material polimer untuk menyusun hidrogel harus dapat mengembang (swell) dan mempertahankan fraksi air pada strukturnya, namun tidak larut dalam air. Polimer alami memiliki gugus fungsi yang dapat menjadi pusat aktif reaksi dimana dapat dilakukan modifikasi untuk menghasilkan suatu polimer dengan karakteristik yang lebih baik. Kitosan merupakan polimer alami yang memiliki kekuatan struktur yang kurang dibandingkan kemampuan swelling. Sintesis hidrogel kitosan dengan metode full interpenetrating polymer network (IPN) dapat meningkatkan kekuatan struktur melalui ikat silang. Tahap pertama adalah sintesis jaringan polimer kitosan terikat silang asetaldehida. Tahap kedua adalah sintesis jaringan polimer PNVCL terikat silang N, N?-metilenbisakrilamida (MBA) melalui polimerisasi radikal bebas monomer NVCL dengan inisiator amonium persulfat (APS). Variasi waktu, rasio kitosan-PNVCL, konsentrasi agen pengikat silang, dan konsentrasi inisiator dipelajari untuk mengetahui kondisi optimum. Kondisi optimum diperoleh pada reaksi 2 jam dengan rasio kitosan/NVCL 90:10 (b/b %), konsentrasi MBA 0,5%, dan konsentrasi APS 3%. HSA kitosan-PNVCL memberikan rasio swelling 380,66% dan derajat ikat silang 60,85%. Karakterisasi HSA dilakukan dengan spektrofotometer Fourier Transform Infrared Spectroscopy (FTIR), Differential Scanning Calorimetry (DSC), Thermogravimetric analysis (TGA), Scanning Electron Microscope (SEM), dan X-Ray Diffraction (XRD).

---

Polymer material used for hydrogel should have the ability to swell and to keep water molecules in its structure without dissolving in water. Natural polymers has functional groups which can perform as active sites in modification to produce polymer with better characteristic. Chitosan is a natural polymer which has good swelling ability but lack of structural strength. Synthesis of chitosan hydrogel by interpenetrating polymer network (IPN) will increase its strength through crosslinking. In this research, the first step of modification was the synthesis of chitosan polymer network crosslinked by acetaldehyde. The next step was the synthesis of PNVCL polymer network crosslinked by N,N-methylbisacrylamide (MBA) through free radical polymerization of NVCL monomer with ammonium persulfat (APS) as the initiatior. Optimum reaction time, chitosan/PNVCL ratio (w/w %), concentration of crosslinker agent, and concentration of initiator had been observed. The optimum conditions were obtained as followed: 2 hours reaction, the ratio chitosan/PNVCL of 90:10 (w/w %), %-w MBA concentration of 0,5%, and APS concentration of 3%. The swelling ratio of the hydrogel was 380,66% while the crosslinking degree was 60,85%. Fourier transfor infrared spectroscopy (FTIR), Differential Scanning Calorimetry (DSC), Thermogravimetric analysis (TGA), Scanning Electron Microscope (SEM), and X-Ray diffraction (XRD) were used for the characterization of the hydrogel."