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Green Synthesis of TiO2 and its Modification with Activated Carbon from Nutmeg Shell for Photodegradation of Chlorpyrifos Pesticide Mutiara Ramadhani1,a, Surya Lubis2,b* and Ilham Maulana2,c 1Graduate school of Chemistry, Faculty of Mathematics and Natural Sciences, Universitas Syiah Kuala, Darussalam 23111, Banda Aceh Indonesia 2Department of Chemistry, Faculty of Mathematics and Natural Sciences, Universitas Syiah Kuala, Darussalam 23111, Banda Aceh Indonesia amutiararamadhani296@gmail.com, bsuryalubis@usk.ac.id, cilham.maulana@usk.ac.id Keywords: TiO2, activated carbon, nanocomposite, nutmeg shell, photodegradation, chlorpyrifos Abstract.
The crystallinity, average crystallite size, and anatase structure of TiO2 are established by X-ray diffraction (XRD), while the morphology and optical property of synthesized materials was analysis by using Scanning Electron Microscopy (SEM), Fourier Transform Infrared (FTIR) spectroscopy and UV-vis diffuse reflectance spectroscopy (UV-Vis DRS).
Characterization Characterization of TiO2 NPs, activated carbon (AC), and AC/TiO2 nanocomposite using XRD were conducted to determine the structure, crystalline phase, purity and crystallite size of TiO2 NPs, activated carbon and AC/TiO2 nanocomposite.
The crystalline structure of TiO2 in TiO2 NPs and 7.5 wt%-AC/TiO2 nanocomposite were similar indicating that the addition of AC into TiO2 NPs had no significant impact on the physical properties of AC/TiO2 nanocomposite.
(a) Fig. 5 (a) UV-Visible absorbance spectrum and the structure of chlorpyrifos pesticide, (b) Absorbance and (c) Degradation % of chlorpyrifos solution under UV light irradiation at different time intervals The addition of AC can enhance the photocatalytic activity of TiO2 NPs by increasing the adsorption of the molecules to the surface of photocatalyst, therefore they can react with the electrons, holes, hydroxyl or superoxide radicals generated after irradiating under UV light [1].

The effects of concentration of TiOSO4 solution and Fe/TiO2 ratio on the structure and pigment properties of the TiO2 white pigments were investigated.
The particle size and distribution, crystal structure, even the precipitation process was the heart of TiO2 production and determines the final pigment quality and yield.
Appropriate crystalline and nice crystal structure was beneficial to improving its pigment properties.
The concentration of TiOSO4 solution influenced the super-saturation of TiO2+, crystal formation, nucleation, crystallization and aggregation process, eventually determined the crystal structure, particle size and its distribution of hydrated TiO2, higher concentration convenient for improving its structure and performances.
Skudlarski: Prace Naukowe Instytutu Chemii Nieorganicznej i Metali Pierwiastków Rzadkich, Politechnika Wroclawska, 22. (1974) [5] Ullmann's Encyclopedia of Industrial Chemistry.

The present work investigated dried calcium phosphate powders which still retain an amorphous or poorly crystalline structure under a variety of conditions.
However, several publications, as well as our previous studies, have shown that calcium phosphate amorphous, or a poorly crystalline structure, can retain their structure even if the samples are dried immediately after synthesis up to 200oC.
What are the optimum drying conditions under which the amorphous calcium phosphate (ACP) structure loses the physically bounded water, but still retains the chemically bounded water?
Produce a calcium phosphate powder with an amorphous structure, and dry it to keep the amorphous structure. 2.
Dowker, Apatite Structures, Adv.

The first applications of light weight carbon/carbon-structures like rocket nozzles, nose caps and CMC-re-entry parts made the modern space flight possible [1, 2].
Fig. 1 shows a typical manufacturing scheme of CMC materials.Figure 1: Manufacturing scheme of CMC-materials The processing of CMC is influenced by the following parameters: • Type of fibers • Reinforcement pattern • Precursor system • Impregnation step • The forming process • Ceramic yield of the precursor • Final heat treatment temperature • Post treatments The selection of the fiber and of the textile structure as well as the fiber orientation is dominating the mechanical properties of the final composite.
Fig. 3: Concentric delaminationsThe corrosion resistance of carbon/carbon crucible for pulling of silicon single crystals can only be achieved by a combination of filament winding and chemical vapor infiltration (CVI) of the carbon/carbon structure after the first pyrolysis step.
The paper structure is pyrolized to carbon/carbon and additionally converted to C/SiC or SiC/SiC.
Huettinger, Chemistry and Kinetics of CVD of pyrocarbon, Carbon 36 (1996), p. 225-232[12] J.

Studies on Adsorption of Tyrosine on Multi-wall Carbon Nanotubes Feng Zhibiao Han Renjiao Wang Jinglong Department of Chemistry, College of Science Northeast Agricultural University Harbin, China Keywords: MWCNTs; tyrosine; adsorption; thermodynamics; kinetics Abstract：The thermodynamics and kinetics properties and mechanism of sorption process were studied for adsorpting tyrosine in aqueous solution with multi-wall carbon nanotubes (MWCNTs), and the adsorption isotherms at different temperatures were determined.
The specific surface area of MWCNTs is rich, mainly provided by the external surface of tube wall and structure defect parts, which supplies tyrosine molecule’s adsorption with numerous adsorption sites; when they take up lots of adsorption sites on MWCNTs surface, the tyrosine molecules continuously diffuse into the accumulation-pore structure of carbon nanotubes aggregates because of the influence of diffusion; major tube pores of MWCNTs belong to mesopore, so in the adsorption process, the adsorption is relatively large.
Progresses of Applied Research for Carbon Nanotubes[J].Nanomaterial & Structure,2004,1:21-24
The Influence of Structure and Surface Property on Hydrogen Storage Ability of Carbon Nanotubes [J].

Hydrocyclone is widely used for classification of fine particles [12-16], because of its compact structure, convenient operation, high separation efficiency and low cost.
Fig. 2 Basic structure of hydrocyclone A hydrocyclone with 25 mm diameter was adopted in this work.
The structure parameters of this hydrocyclone are shown in Table 1.
Table 1 Basic structure parameters of hydrocyclone de /D a/b do/D Do/D L0/D L1/D /(°) du/D 0.22 1.5 0.24 0.68 0.57 1.48 6 0.08 Operating conditions The flotation machine worked at 1924 rpm of the impeller wheel speed.
Analytical Chemistry, 1978, 50(8): 1032-1040

Our previous works have shown that the transport-induced de-screening is significant at nanoslit structures under the bias of ~ 15 V [11].
This study indicates that a similar effect is also presented at nanopore structures.
As the thickness of the nanopore structures (~ 50 nm) is much smaller than the nanoslit (~ 1000 nm), the effective electrical field is much higher.
The transport-induced de-screening effect can be presented at a low bias (~ 1V) in this case comparing rather high bias (~ 20 V) for the nanoslit structure.
Liu, “Transport-Induced Inversion of Screening Ionic Charges in Nanochannels,” The Journal of Physical Chemistry Letters, pp. 5235–5241, Dec. 2016

Preparation and Application of Microencapsulated Flame Retardant Containing Phosphorus-silicon Yong Yang1, a, Jialong Fang2, b, Miao Lin2, c * 1 Inspection Center of Industrial Product & Raw Materials, Shanghai Entry-Exit Inspection & Quarantine Bureau, Shanghai 200135, China 2 College of Chemistry, Chemical Engineering and Biotechnology, Key Laboratory of Science & Technology of Eco-Textile (Donghua University), Ministry of Education, Donghua University, Shanghai 201620, China ayyangk@online.sh.cn, bfangjl@mail.dhu.edu.cn, clinmiao@dhu.edu.cn *correspondent author Keywords: Microencapsulated Flame Retardant, Phosphorus-silicon Synergistic Effect, Sol-gel Technique, Flame Retarding Efficiency.
The structure of silica gel was characterized with the NEXUS-670 Fourier Transform Infrared-Raman spectrometer, which was used to show the structure of dried silica gel and the modified microencapsulated flame retardant.
The Structure of Silica Gel.
The Structure of Modified Flame Retardant.

Some empirical equations have been deduced relating the ductile-brittle transition temperature to the steel chemistry and to the above mentioned grain size.
proposed a dependence of 50% FATT on packet size d in bainitic structures, with a value for the ∆FATT/∆d-1/2 coefficient identical to that measured for ferrite [5]; Matsuda and Naylor [6, 7] related 50% FATT to other parameters, as the Unit Crack Path (UCP), anyway directly related to the size of the covariant packet; Brozzo et al. [8] showed that in the case of low-C bainitic steels the mechanical strength and cleavage resistance appear to be controlled by different structural parameters and not, as on the case of polygonal ferrite steels, by the same structural unit.
It is known that when at NDT fracture coincides with the general yield the critical cleavage stress can be calculated from the uniaxial yield stress σy by the following relationship, according to the Tresca criterion [15]: y cf σ σ ⋅= 24.2 (1) Results and discussion Microstructure and yield strength From the microscopic examination it resulted that steels A and B had a tempered bainitic structure whereas steels C-D had a tempered martensitic structure.
TEM investigation by thin foils (Figure 1a) showed that bainite appears characterised by the presence of intralath aligned cementite; moreover, the cell structure is clearly revealed in the bainitic steel, deriving from the transformation of prior austenitic grains.

Over time these original ferrite chemistries were rejected for the reason that the final production contained too much ferrum which was hard to get rid of from aluminum.
The photos clearly showed that the metal agglomerated and separated without NiO, while the net structure of metal phase formed after adding NiO.
Because the metal was the main distributor to the electrical conductivity of the inert anodes, net structure of metal definitely increased the conductivity.
Therefore, net structure of metal will form if the NiO particles are evenly distributed.
Because nickel has better wetting property on NiO than on NiAl2O4, net structure of metal formed in the inert anodes with NiO added.