An Empirical Formula Expressing the Mutual Dependence of C-C Bond Distances

An empirical formula is suggested to describe the mutuaJ dependence of the length of the bonds formed by a central atom in systems built up from equivalent carbon atoms, e.g. diamond, graphite, the cumulene and polyyne chains and intermediate structures between them. A geometrical representation of the relationship is a regular tetrahedron. A point of this tetrahedron characterizes the arrangement of the atoms around the central one. From the position of the point the bond distances - and possibly the bond angles - can be deduced

Phytochemical Tests and Antioxidant Activities of the Rhips Ginger (Zingiber Officinale Var Amarum.)

Ginger is a traditional plant that thrives and has essential functions, including an antioxidant. This study aimed to determine the phytochemical content and test the antioxidant activity of fresh white ginger and powdered ginger (Zingiber officinale var. Amarum.). Two methods are used in this research: the phytochemical test and the antioxidant activity test using DPPH. Phytochemical tests, such as flavonoid, phenolic, steroid, and saponin, were conducted qualitatively. The antioxidant activity test was carried out using a UV-Vis spectrophotometer. Fresh white ginger and powdered ginger were extracted using the maceration method with water solvent. The study results showed that the effects of fresh white ginger extract obtained a yield of 64.08%. Meanwhile, powdered ginger extract was 58.68%. Phytochemical test results of fresh white ginger extract and powdered ginger (commercial) showed positive results for flavonoid, phenolic, and saponin compounds while adverse effects for steroids. Antioxidant activity test on fresh white ginger extract with water solvent showed an IC50 value of 25.41 ppm. The powdered ginger extract (commercial) has an IC50 value of 36.70 ppm. The results showed fresh white ginger and powdered ginger had relatively high antioxidant activity

Optimation Transesterification Reaction Conditions on Biodiesel Production From Beef Tallow

Biodiesel synthesis has been done from beef tallow through two step, esterification and transesterification reactions. Esterification process is done by using  H2SO4 1M as a catalyst, methanol 1:9, temperature of 60-65°C, and for 3 hours. After separated between methanol and trigyceride, then proceed to the process of transesterification. To obtain the optimum reaction conditions then used some transesterification process variables,  there are: the weight percentage catalyst of KOH between 0.1, 0.5, 1; 1.5, and 2%, the reaction time of 1-5 hours and the reaction temperature between 50 -70 oC. Optimum conditions of transesterification reaction for the synthesis of biodiesel derived from beef tallow with KOH catalyst is as follows: the weight percentage of 1% KOH catalyst, the reaction time of 3 hours and the reaction temperature of 65 oC. The results of physical testing of biodiesel fuel by ASTM method includes specific density of 0.8675 g/cm3, kinematic viscosity of 4.971 mm2/s, flash point of 134.5°C, pour point of 27°C, the Conradson carbon residue of 0.018%, and the copper corrosion-pieces of 1B

Isoterm Adsorpsi Ion Cr(III) Oleh Kitosan Hasil Isolasi Limbah Kepiting Rajungan dan Kitosan Komersil

The chitin isolation from crab Rajungan (Portunus sanginolentus) and commercial chitin was done. The chitosan was made by deasetilation of chitin using alkaline solution with addition NaBH4. The chitin and chitosan were identified by related instrument. The identification by adsorption Cr(III) ion on chitosan was done by the Atomic Absorption Spectrofotometry. The result of the chitosan isolation was fitted to the Freundlisch isotherm, with KF = 1.18673 mg/g and 1/n= 0.2712.&nbsp

Kinetic Parameters Determination Of Glucoamylase On Hydrolysis Reaction Of Sagoo Starch (Metroxylon sp)

Sagoo plant (Metroxylon sp.) numerous in eastern Indonesia, such as Maluku and Papua. Sagoo starch containing amylose and amylopectin. Sagoo starch hydrolysis can be carried out by enzymes, such as glucoamylase or often called amiloglukosidase or α-1 ,4-glukanoglukohidrolase, an extracellular enzyme capable hydrolyzes α-1, 4 on amylose and α-1, 6 in amylopectin. The enzymatic hydrolysis of starch can be reviewed in the kinetics of the Michaelis-Menten equation and Lineweaver-Burk equation. The aims of this study to determine the kinetic parameters (Vmax and Km) of glucoamylase on hydrolysis of sagoo starch. Glucoamylase has an optimum temperature of 50 oC and pH optimum 6.5. At optimum conditions, based on Michaelis-Menten equation, the value of Vmax is 1.09 U / mL / min and Km value is 0.82. Based on Lineweaver-Burk equation, the value of Vmax was 1.03 U / mL / min and Km value was 0.84%

Isolasi Kitosan Dari Tudung Jamur Merang (Vollvariella Volvaceae) Dan Aplikasinya Sebagai Absorben Logam Timbal (Pb)

Chitosan isolated from mushroom (Vollariella volvaceae) as adsorbent of lead (Pb) metal has been done.  The isolation of chitosan was obtained 2.94% from total weight of mushroom.  Fungtional groups of chitin and chitosan were indentified by using FTIR spectrophotometry.  The chitosan had 74.66% degree of deacetylation and 2.09 x 104 g/mol viscosity molecular weight.  The experimental data of the chitosan as adsorbent for Pb metal were correlated with the Langmuir and Freundlich isotherm model.  The maximum adsorption capacity of Pb based on the Langmuir isotherm model was 2.66 mg/g

Kinetic Parameters Determination Of Glucoamylase On Hydrolysis Reaction Of Sagoo Starch (Metroxylon sp)

Sagoo plant (Metroxylon sp.) numerous in eastern Indonesia, such as Maluku and Papua. Sagoo starch containing amylose and amylopectin. Sagoo starch hydrolysis can be carried out by enzymes, such as glucoamylase or often called amiloglukosidase or α-1 ,4-glukanoglukohidrolase, an extracellular enzyme capable hydrolyzes α-1, 4 on amylose and α-1, 6 in amylopectin. The enzymatic hydrolysis of starch can be reviewed in the kinetics of the Michaelis-Menten equation and Lineweaver-Burk equation. The aims of this study to determine the kinetic parameters (Vmax and Km) of glucoamylase on hydrolysis of sagoo starch. Glucoamylase has an optimum temperature of 50 oC and pH optimum 6.5. At optimum conditions, based on Michaelis-Menten equation, the value of Vmax is 1.09 U / mL / min and Km value is 0.82. Based on Lineweaver-Burk equation, the value of Vmax was 1.03 U / mL / min and Km value was 0.84%

Pembuatan Kecap sebagai Bahan Tambahan Makanan dari Limbah Air Kelapa di Negeri Kilang

Provinsi Maluku adalah provinsi kepulauan yang memiliki banyak desa yang secara geografis berada di pinggran pantai. Negeri Kilang merupakan salah satu desa di Pulau Ambon, Sumber penghasilan rata-rata keluarga warga desa ini adalah nelayan dan petani. Salah satu tanaman yang dihasilkan masyarakat Kilang adalah tanaman kelapa. Sebagai bentuk pengabdian masyarakat yang merupakan bagian dari tugas Tri Dharma Perguruan Tinggi maka perlu adanya pemberian informasi berupa inovasi untuk memanfaatkan air kelapa menjadi sesuatu produk yang bermanfaat dan turut dapat menjadi sumber perekonomian yang dapat meningkatkan pendapatan masyarakat desa dalam bentuk pengabdian mayarakat.  Hal ini dapat dilakukan dengan pelatihan yang ditujukan kepada masyarakat Negeri Kilang untuk dapat memanfaatkan air kelapa tersebut menjadi barang yang bernilai ekonomi. Limbah air kelapa yang dihasilkan tersebut dapat dijadikan bahan tambahan makanan sebagai penambah rasa atau bumbu pada makanan yakni kecap

Kinetic Parameters Determination Of Glucoamylase On Hydrolysis Reaction Of Sagoo Starch (Metroxylon sp)

Sagoo plant (Metroxylon sp.) numerous in eastern Indonesia, such as Maluku and Papua. Sagoo starch containing amylose and amylopectin. Sagoo starch hydrolysis can be carried out by enzymes, such as glucoamylase or often called amiloglukosidase or α-1 ,4-glukanoglukohidrolase, an extracellular enzyme capable hydrolyzes α-1, 4 on amylose and α-1, 6 in amylopectin. The enzymatic hydrolysis of starch can be reviewed in the kinetics of the Michaelis-Menten equation and Lineweaver-Burk equation. The aims of this study to determine the kinetic parameters (Vmax and Km) of glucoamylase on hydrolysis of sagoo starch. Glucoamylase has an optimum temperature of 50 oC and pH optimum 6.5. At optimum conditions, based on Michaelis-Menten equation, the value of Vmax is 1.09 U / mL / min and Km value is 0.82. Based on Lineweaver-Burk equation, the value of Vmax was 1.03 U / mL / min and Km value was 0.84%