UV Protectants for the Biopesticide Based on Photostabilization of Ecdysone

2011 ◽  
Vol 183-185 ◽  
pp. 401-405 ◽  
Author(s):  
Hua Nan Guan ◽  
De Fu Chi ◽  
Jia Yu
Keyword(s):  
Ultraviolet Light ◽  
Larvicidal Activity ◽  
Half Life ◽  
Moderate Degree ◽  
Order Kinetic ◽  
Synthetic Compounds ◽  
First Order ◽  
Glass Slides ◽  
Life Values ◽  
Order Kinetic Equation

The ultraviolet protectant (UV protectant) properties of different natural and synthetic compounds were investigated for a biopesticide based on ecdysone. This study examined the photostabilization of ecdysone when exposed to ultraviolet light in the presence of some ultraviolet protectants. Ecdysone solutions with and without UV protectants in methanol were applied onto the surface of glass slides. At particular intervals, the remaining concentration of ecdysone was analyzed by HPLC. Using first-order kinetic equation, the dissipation half-life values (DT50) for the degradation of ecdysone under ultraviolet radiation were obtained. The larvicidal activity was evaluated against the larvae of Martianus dermestoides Chevrolat. It indicated that the addition of congo red, yeast, starch and arabia gum provided moderate degree of photostabilization of ecdysone and that addition of lignin provided the best photostabilization of ecdysone, among these UV protectants studied. Toxicity of the ecdysone with UV protectants was higher to the larvae of M. dermestoides Chevrolat compared to the ecdysone alone as indicated by the lower EC50 value. The dissipation half-life values of ecdysone after irradiation under ultraviolet light and the larvicidal activity suggested that the addition of lignin (in 1:l mol ratio) can provide better photostabilization of ecdysone molecule.

scholarly journals Effect of inoculum to substrate ratio on biogas production of sheep paunch manure

2016 ◽  
Vol 62 (No. 1) ◽  
pp. 8-14 ◽  
Author(s):  
A.A. Lawal ◽  
A.U. Dzivama ◽  
M.K. Wasinda
Keyword(s):  
Biogas Production ◽  
Coefficient Of Determination ◽  
Order Kinetic ◽  
Production Rates ◽  
Exponential Equation ◽  
First Order ◽  
Gompertz Equation ◽  
Volatile Solids ◽  
Substrate Ratio ◽  
Order Kinetic Equation

Sheep paunch manure was anaerobically digested to study the effect of inoculum to substrate ratio on biogas production rates and accumulation. Inoculum to substrate ratios of 1.37, 2.05 and 4.1 were digested in biodigesters labelled R1, R2 and <br /> R3 respectively. Results showed that inoculum to substrate ratio had a significant effect on biogas production rates and accumulation. Biogas production rates increased to peak in the order of R3 (0.30526 Nm<sup>3</sup>/kg volatile solids (VS) days), R2 (0.15308 Nm<sup>3</sup>/kg VS d) and R1 (0.11009 Nm<sup>3</sup>/kg VS d) on the 5<sup>th</sup> day. The biogas production accumulation increased from 0.57195 to 1.46784 Nm<sup>3</sup>/kg VS as the inoculum to substrate ratio increased. The result of regression showed that coefficient of determination values for the linear equation ranged from 0.707 to 0.797, while the exponential equation had higher values that ranged from 0.7718 to 0.9929 showing better simulation. The modified Gompertz equation showed better simulation of the biogas production accumulation than the first order kinetic equation due to its higher coefficient of determination values.

Degradation of 4-nitrophenol using the Fenton process

2000 ◽  
Vol 42 (3-4) ◽  
pp. 155-160 ◽  
Author(s):  
Y.-S. Ma ◽  
S.-T. Huang ◽  
J.-G. Lin
Keyword(s):  
Kinetic Equation ◽  
Nitrogen Concentration ◽  
Order Kinetic ◽  
Fenton Process ◽  
Nitrogenous Compounds ◽  
First Order ◽  
Degradation Rate Constant ◽  
Before And After ◽  
Pseudo First Order ◽  
Order Kinetic Equation

In this study, The Fenton process was applied as a pretreatment method to treat industrial wastewater containing 4-nitrophenol (4-NP). The effect of oxidant dosages on the decomposition of 4-NP and the reaction kinetics were investigated. More than 99% of 4-NP was readily decomposed when the reaction was carried out at oxidant concentrations of 5 mM H2O2 and 5 mg/L Fe2+ for 2 hours. The total nitrogenous compounds and the nitrogen gas evolved, accounted for 88% of the initial nitrogen concentration. However, the maximum DOC removal efficiency was 30.6%; and only 1/3 of 4-NP was mineralized to carbon dioxide by the Fenton process. 4-NP degradation profiles fitted well into a pseudo first-order kinetic equation; degradation rate constant (min-1) of 4-NP increased from 4.3×10-3 to 66.1×10-3 with increasing dosages of H2O2 and Fe2+. In addition, the t value was calculated for studying the significance of simulation by the t-test. It was found that the t value was greater than the value for 99% confidence. This result suggested that the 4-NP decomposition profile could be described by the pseudo first-order kinetic equation. Biodegradability of 4-NP before and after the reaction was 0.018 and 0.594, respectively.

Performance evaluation of anoxic and facultative wastewater stabilization ponds

1996 ◽  
Vol 33 (7) ◽  
pp. 141-145 ◽  
Author(s):  
Muwaffaq M. Saqqar ◽  
M. B. Pescod
Keyword(s):  
Performance Evaluation ◽  
Kinetic Equation ◽  
Simple Model ◽  
Operating Time ◽  
Order Kinetic ◽  
Sediment Depth ◽  
First Order ◽  
Maximum Value ◽  
Wastewater Stabilization Ponds ◽  
Order Kinetic Equation

The performance of anoxic and facultative ponds in Jordan was investigated for 12 months. Calculated values of the first order kinetic equation rate for CBOD removal (KCBOD) has resulted in different KCBOD's for different ponds in the same month, at the same temperature. It is evident that factors other than temperature must influence values of KCBOD. The KCBOD values determined were generally lower than those reported in the literature. The maximum value found was only 0.16 (/day). A pond was emptied after 18 months of operation and sediment was found randomly distributed over the pond area, with a depth ranging from 2 to 6 cm (averaging ≈ 4 cm). A simple model has been established to estimate sediment depth (Hs in cm) in terms of the operating time in months (t).

Characterization of Dioctyl terephthalate biodegradation by food waste composting

2019 ◽  
Vol 33 (14n15) ◽  
pp. 1940048 ◽  
Author(s):  
Sung Tse Lee ◽  
Huu Tuan Tran ◽  
Chitsan Lin ◽  
Hong Giang Hoang ◽  
Thi Dieu Hien Vo ◽  
...  
Keyword(s):  
Removal Efficiency ◽  
Food Waste ◽  
Half Life ◽  
Order Kinetic ◽  
Aerobic Composting ◽  
First Order ◽  
Competitive Process ◽  
Plastic Products

Dioctyl terephthalate (DOTP), a plasticizer is used as an additive in many plastic products. Disposal of DOTP into environment has been of concern because it is hardly biodegradable in nature. Therefore, the aim of this study is to investigate the biodegradation of DOTP by aerobic composting processes without bioaugmentation. The initial DOTP concentration in the compost mixture was 11,882 mg/kg, after 35-day incubation, the removal efficiency of the compost reactor was 98%. The degradation was found to follow the first-order kinetic with the half-life of 5.2 days. Food waste composting was demonstrated as a technically robust and economically competitive process for the degradation of DOTP, and that of other similar plasticizers are expected.

scholarly journals Study on environmental behaviour of fluopyram in different banana planting soil

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Jia Zhou ◽  
Shuilian Liang ◽  
Yuanyuan Cui ◽  
Yu Rong ◽  
Jia Song ◽  
...  
Keyword(s):  
Sandy Soil ◽  
Alluvial Soil ◽  
Order Kinetic ◽  
Environmental Behaviour ◽  
First Order ◽  
Degradation Rates ◽  
And Migration ◽  
Agricultural Areas ◽  
Banana Leaf ◽  
Order Kinetic Equation

AbstractFluopyram is commonly used to control banana leaf spot, anthracnose, and scab in tropical agricultural areas. To explore its behaviour in tropical agricultural environments, dissipation, adsorption, and leaching behaviours of fluopyram in three typical banana planting soils were studied. Also, its dissipation and migration capabilities in different regions and different soil types were evaluated. The results showed that the dissipation of fluopyram was in accordance with the first-order kinetic equation in the three banana soils, but the degradation rates were quite different. The degradation half-lives in the Hainan latosol, Yunnan sandy soil, and Fujian Plain alluvial soil were 46.21 days, 36.48 days and 57.76 days, respectively. Fluopyram also exhibited high adsorption and low leachability in the three soils. The Fujian Plain alluvial soil had the highest adsorption capacity for fluopyram, while fluopyram had the low leachability in the Yunnan sandy soil.

scholarly journals Differential Thermal Analysis of Tobacco as a Function of Heating Rate

1977 ◽  
Vol 9 (1) ◽  
Author(s):  
C. O. Tiller ◽  
E. M. Gentry
Keyword(s):  
Thermal Analysis ◽  
Differential Thermal Analysis ◽  
Heating Rate ◽  
Characteristic Temperature ◽  
Inert Atmosphere ◽  
Order Kinetic ◽  
First Order ◽  
Reconstituted Tobacco Sheet ◽  
Decomposition Processes ◽  
Order Kinetic Equation

AbstractThe differential thermal analysis of reconstituted tobacco sheet heated at rates of 0.1°C/s to 500°C/s in an inert atmosphere is reported. As the heating rate is increased, the characteristic temperature of each global process observed is increased. Using a non-isothermal first-order kinetic equation, the activation energies and frequency factors are obtained for these bulk decomposition processes

scholarly journals STABILITY OF CHITOSAN-TRIPOLYPHOSPHATE COMPLEX-ENCAPSULATED ANTHOCYANIN AT HIGH WATER ACTIVITY

2020 ◽  
Vol 31 (2) ◽  
pp. 171-179
Author(s):  
Umi Laila ◽  
◽  
Rochmadi Rochmadi ◽  
Sri Pudjiraharti ◽  
Rifa Nurhayati ◽  
...  
Keyword(s):  
Water Activity ◽  
Half Life ◽  
Incubation Temperature ◽  
Kinetic Constant ◽  
Food Product ◽  
High Water ◽  
Order Kinetic ◽  
Degradation Kinetic ◽  
First Order ◽  
The Stability

Previous study successfully conducted encapsulation of the purple-fleshed sweet potato’s anthocyanin but the study has yet to reveal the stability of encapsulated anthocyanin. Therefore, this research aims to observe the stability of encapsulated anthocyanin regarding the characteristic of low anthocyanin stability, which depends on environmental factors, such as temperature, pH, humidity, and water activity. The kinetic parameters of stability, including kinetic constant (k), reaction order, and half-life (t1/2), were also studied. Stability testing was conducted in high water activity of 0.75 and various in-cubation temperatures at 16, 25, 35, and 45°C. Un-encapsulated anthocyanin extract was also tested for its stability in the same condition in order to be compared with encapsulated anthocyanin. This study re-vealed that the encapsulated anthocyanin had lower stability than un-encapsulated anthocyanin extract. It was proven by higher kinetic constant and lower half-life of encapsulated anthocyanin for every incubation temperature which was induced by higher pH of encapsulated anthocyanin compared with anthocyanin extract. Besides, high water activity reduced glass transition temperature (Tg), in which encapsulated anthocyanin was in rubbery state. Both encapsulated anthocyanin and anthocyanin extract were degraded following the first order kinetic. Using the Arrhenius equation, it was obtained that the degradation kinetic constant of encapsulated anthocyanin was stated as k= 420.44 exp (-23.33/RT). Meanwhile, k= 1.12x106 exp (-46.70/RT) described degradation of kinetic constant of anthocyanin extract. The stability test re-vealed that the application of encapsulated anthocyanin was not suitable for wet-type food product.

scholarly journals Frustrated Lewis Pair Stabilized Phosphoryl Nitride (NPO), a Mono Phosphorus Analogue of Nitrous Oxide (N2O)

2021 ◽  
Author(s):  
André Eckhardt ◽  
Martin-Louis Riu ◽  
Peter Müller ◽  
Christopher Cummins
Keyword(s):  
Nitrous Oxide ◽  
Half Life ◽  
Negative Charge ◽  
Activation Enthalpy ◽  
Activation Entropy ◽  
Order Kinetic ◽  
Reactive Intermediate ◽  
First Order ◽  
Frustrated Lewis Pair ◽  
Good Agreement

Phosphoryl nitride (NPO) is a highly reactive intermediate, and its chemistry has only been explored under matrix isolation conditions so far. Here we report the synthesis of an anthracene (A) and phosphoryl azide-based molecule (N3P(O)A) that acts as a molecular synthon of NPO. Experimentally, N3P(O)A dissociates thermally with a first order kinetic half-life that is associated with an activation enthalpy of ΔH⧧ = 27.5 ± 0.3 kcal mol–1 and an activation entropy of ΔS⧧ = 10.6 ± 0.3 cal mol–1 K–1 that are in good agreement with calculated DLPNO-CCSD(T)/cc-pVTZ//PBE0-D3(BJ)/cc-pVTZ energies. In solution N3P(O)A undergoes Staudinger reactivity with tricyclohexylphosphine (PCy3) and subsequent complexation with tris(pentafluorophenyl)borane (B(C6F5)3, BCF) to form Cy3P-NP(A)O-B(C6F5)3. Anthracene is cleaved off photochemically to form the frustrated Lewis pair (FLP) stabilized NPO complex Cy3P⊕-N=P-O-B⊖(C6F5)3. Intrinsic Bond Orbital (IBO) analysis suggests that the adduct is zwitterionic, with a positive and negative charge localized on the complexing Cy3P and BCF, respectively.

Process Mineralogy and Flotation Kinetic of a Copper Oxide Ore during Sulfuration Flotation

2013 ◽  
Vol 634-638 ◽  
pp. 3460-3465 ◽  
Author(s):  
Kun Xiong ◽  
Gui Shan Zheng
Keyword(s):  
Kinetic Equation ◽  
Copper Oxide ◽  
Kinetic Equations ◽  
Order Kinetic ◽  
Copper Ore ◽  
Total Recovery ◽  
Flotation Process ◽  
First Order ◽  
Process Mineralogy ◽  
Order Kinetic Equation

This study aims to investigate the process mineralogy of the Dishui copper ore in Xinjiang and determine the flotation kinetic equations of this copper ore during the sulfuration flotation process. The results indicate cuprite is the main form of oxide copper minerals, which is difficult to be vulcanized and floated. The fitting of flotation date to a flotation kinetic equation shows that the copper oxide ore, cuprite, malachite and chrysocolla in this ore are consistent with a first order kinetic equation. The rate constants for copper oxide, cuprite, malachite and chrysocolla are 0.152, 0.104, 0.248 and 0.210 respectively. Thus, the flotation of cuprite in the ore is very important to improve the total recovery of the copper oxide ore.

Sign in / Sign up

Export Citation Format

Share Document