Search

Water pollution is a major environmental concern worldwide, particularly due to industrial paint waste. Therefore, treating wastewater from various industrial sources is crucial to restoring environmental quality. In this study, a batch biosorption system was used to investigate the biosorption of Rhodamine B (RhB), a highly toxic dye, on Teucrium polium seeds (TPS). The study examined the effects of different parameters such as initial dye concentration, contact time, initial pH, temperature, and biosorbent amount on RhB removal. To determine the physicochemical properties of TPS, scanning electron microscopy (SEM), energy-dispersive X-ray (EDX), Fourier transform infrared spectroscopy (FTIR), Brunauer-Emmett-Teller (BET), and zero charge point (PZC) characterization analyses were performed. The maximum biosorption capacity of TPS at pH = 5.5 and 25 °C was found to be 4.18 mg g−1. The study found that the removal rate of RhB was 93.3% at an initial RhB dye concentration of 200 mg L−1. The experimental data showed that the Langmuir isotherm model (R2 = 0.940) was the most compatible model for biosorption, while the biosorption kinetic mechanism proceeded through the pseudo-second-order (PSO) kinetic model (R2 = 0.925). Additionally, the study found that intraparticle diffusion, pore diffusion, and film diffusion were effective in the RhB biosorption rate mechanism. Thermodynamic studies revealed that the biosorption was endothermic (ΔH0>0), spontaneous (ΔS0>0), and entropy-increasing (ΔG0 <0). As a result, TPS, which has suitable adsorbent properties for RhB, can be recommended as a new, cost-effective, abundant potential biosorbent. [ABSTRACT FROM AUTHOR]

In this work, the heavy metal chelating agent N, N-bis(dithiocarboxy) ethylenediamine (EDTC) was synthesized by blending method with ethylenediamine (C2H8N2) and carbon disulfide (CS2). The effects of material ratio, dosing sequence, pH and temperature in aqueous solution on the removal characteristics of EDTC as a synergistic agent for the treatment of complexed copper (EDTA-Cu) and Rhodamine B (RhB) were investigated. Furthermore, the removal efficiency was compared with those of single-component EDTA-Cu and RhB systems. The results indicated that the removal of EDTA-Cu and RhB was up to 150 mg/g and 850 mg/g, respectively, when 1.3 g/L EDTC was added to 180 mg/L EDTA-Cu and 1 800 mg/L RhB water at room temperature. The treatment efficiency was stable in the pH range of 2-10 in aqueous solution. Compared with the removal effect of single component EDTA-Cu and RhB treated with EDTC, EDTC can effectively simultaneous remove copper and RhB with synergistic effect. Therefore, EDTC can be applied as a water treatment agent for the synergistic treatment of complex metal and dye in complicated wastewater.

Copyright of Industrial Water Treatment is the property of CNOOC Tianjin Chemical Research & Design Institute and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The electrocoagulation method has been proven to be highly effective in removing metal ions from water, with a removal efficiency of over 97%. However, in terms of removing organic pollutants such as synthetic dyes, the efficiency of electrocoagulation is still relatively low. A hybrid approach combining electrocoagulation with membrane filtration has been proposed to enhance the removal of organic contaminants. Eco-friendly membranes made from renewable natural polymers like carrageenan and chitosan, reinforced with synthetic polymers such as polyvinyl alcohol and carbon nanotubes, have shown to be promising for this application. In this study, membranes with varying chitosan/carrageenan ratios of 0.2, 0.33, 0.5, and 0.71 (g/g) were used to remove synthetic dyes, including methylene blue, rhodamine B, bromocresol purple, and murexid, at a concentration of 200 ppm from 8.5 ml of water. From the SEM images, the four membranes have almost the same surface and cross-section morphology. The results showed that the membrane with a chitosan/carrageenan ratio of 0.71 exhibited the highest removal efficiency for all synthetic dyes. The parameter affecting the membrane's removal efficiency is the interaction between the membrane and synthetic dyes. Murexid, an anionic dye, achieved a 100% removal efficiency, surpassing cationic dyes such as rhodamine B and methylene blue. Besides interactions, the dye's molecular size determines the removal's efficiency. The molecular size of rhodamine B is larger than that of methylene blue, and the removal efficiency of rhodamine B (98.4%) is greater than methylene blue (91%). Bromocresol purple is almost the same size as rhodamine B but not ionic because it has the lowest removal efficiency of 34.55%. [ABSTRACT FROM AUTHOR]

Photocatalysis employing Metal-Organic Framework (MOF) material may degrade Rhodamin B pollutant. MOF photocatalytic activity can be adjusted by altering the ligands, metal ions, and modulators. This research aims to synthesize glycine-modulated zirconium perylene-based metal organic framework (Zr-PTCA-Gly) for Rhodamin B photocatalytic degradation under visible light irradiation. The activated Zr-PTCA-Gly 1:10 exhibits good catalytic activity to degrade Rhodamine B with a 95.8% degradation efficiency. [ABSTRACT FROM AUTHOR]

A greener approach was applied for gold nanoparticles (AuNPs) synthesis via simple, non-hazardous and environment-friendly route utilizing the fruit peel extract of Manilkara zapota (sapodilla). The phytochemical screening of peel extract revealed that this extract act as a reductant and stabilizer concurrently for surface-functionalized AuNPs synthesis. The UV-Vis spectroscopy, FTIR, XRD, SEM-EDX and HR-TEM were employed to confirm the fabricated AuNPs. Moreover, a proficient fluorescence approach for the determination of thiourea (TU) based on fluorescence resonance energy transfer between rhodamine B (RB) and synthesized AuNPs, promotes fluorescence quenching. On addition of TU, the fluorescence of RB was recovered due to competitive adsorption between thiourea and RB on the surface of AuNPs, Which induces further aggregation of AuNPs. In optimal state, the linear relationship between the fluorescence recovery efficiency and TU concentration with the linear range from 0.02 − 1.0 ppm and the calculated detection limit was 0.017 ppm. The proposed fluorometric method was effectively utilized for TU detection in the actual sample with a good recovery percentage. [ABSTRACT FROM AUTHOR]

Latar Belakang: Perona pipi merupakan kosmetik yang banyak digunakan oleh wanita, salah satu bahan berbahaya yang dapat terkandung dalam perona pipi adalah Rhodamin B yang digunakan pada industri tekstil, kertas, dan cat. Paparan secara langsung Rhodamin B pada kulit dapat menghambat proliferasi fibroblas sehingga kulit menjadi kering dan penyerapan secara sistemik dapat menyebabkan gangguan pada hepar. Objektif: Mengidentifikasi kandungan Rhodamin B pada perona pipi yang beredar di Kecamatan Lubuk Begalung Kota Padang. Metode: Identifikasi kualitatif kandungan Rhodamin B dilakukan menggunakan Rapid Test Kit Rhodamin B yang dilakukan di Laboratorium Biokimia Fakultas Kedokteran Universitas Andalas. Hasil: Hasil penelitian ini menunjukkan dari 13 sampel perona pipi yang beredar di Kecamatan Lubuk Begalung Kota Padang lebih dari separuh sampel (61,5%) merupakan perona pipi yang terdaftar dalam BPOM dan kurang dari separuh (38,5%) merupakan perona pipi yang tidak terdaftar dalam BPOM. Kesimpulan: Dari penelitian ini disimpulakan hanya satu sampel yang positif mengandung Rhodamin B yaitu dari sampel perona pipi yang terdaftar dalam BPOM.

Rhodamine B is a colorant in the form of odorless crystals and is green or reddish purple in color which is circulating in the market for the industry as a textile dye. The purpose of this study was to determine and identify the presence or absence of synthetic dye Rhodamine B in red crackers circulating in the Rawasari Cempaka Putih Traditional Market. This research is experimental by conducting qualitative laboratory tests using thin layer chromatography method and quantitative testing using UV Vis spectrophotometry method. Sampling used a technique in the form of Random Sampling, which is a random sampling method in the Rawasari Cempaka Putih traditional market. There is a synthetic dye content Rhodamine B in one of the red cracker samples circulating in the Rawasari Cempaka Putih Traditional Market. [ABSTRACT FROM AUTHOR]

Pendahuluan: Rhodamin B adalah pewarna sintetik yang umum digunakan sebagai pewarna tekstil, Rhodamin B dalam makanan dapat menyebabkan keracunan, sehingga Rhodamin B dilarang digunakan sebagai bahan tambahan pangan. Tujuan: Penelitian ini bertujuan untuk menguji secara kualitatif dan kuantitatif adanya Rhodamin B dalam kue bolu kukus yang beredar di Kota Jambi. Metode: Pengambilan sampel dilakukan secara acak dalam 8 kecamatan dari 11 kecamatan di Kota Jambi. Analisis Rhodamin B pada kue bolu kukus ini ditentukan dengan 2 metode yaitu Kromatografi Lapis Tipis dan Spektrofotometri UV-Vis. Pada analisa kualitatif dengan Kromatografi Lapis Tipis menggunakan plat silica gel GF 254 dengan mengunakan fase gerak campuran n-butanol : asam asetat : ammonia dengan perbandingan (10 : 4 : 5). Hasil: Hasil dari analisis Rhodamin B yang dilakukan dengan KLT didapatkan nilai Rf sama antara sampel dengan pembanding Rhodamin B yaitu 0,8. Spektrofotometri UV-Vis didapat panjang gelombang maksimum 557 nm, dan diperoleh kadar Rhodamin B pada sampel B 0,88210 µg/mL, sampel E 1,3475 µg/mL dan sampel F 0,80684 µg/mL. Kesimpulan: Hasil uji identifikasi menunjukan bahwa dari 8 sampel kue bolu kukus, 3 sampel diantaranya positif mengandung pewarna Rhodamin B.

Copyright of Jurnal Agroindustri Halal is the property of Universitas Djuanda and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Introduction: Food circulation among communities is prone to chemical contamination. The contamination is obtained from both food processing and food cultivation (planting, raw materials). One of the examples related to chemical contamination can be seen in the contamination of rhodamine B on Terasi. Although there is a prohibition on using Rhodamine B compounds in food add-ons, which is listed in Regulation of Ministry of Health of Republic Indonesia No.722/Menkes/Per/IX/1988, its usage is widely found. Similarly, chlorpyrifos pesticide residue in lalapan is the other example provided. The usage of it remains to continue even though the result of pesticide residue value is under BMR SNI 7313:2008. The article aims to study food processing efforts in minimizing the chemical contamination of Rhodamine B in shrimp terasi and chlorpyrifos residue in the lalapan vegetables in the communities in Indonesia. A literature review on scientific publications was undertaken through Google Scholar, ResearchGate, Neliti, ScienceDirect, LIPI, Directory Open Acces Journal, and Crossref. The keywords used were related to rhodamin B on terasi, synthetic dyes on terasi, natural dyes for terasi, vegetable pesticide residues, Chlorpyrifos residue on vegetables, and how to reduce chlorpyrifos residue in vegetables. All of them were published between the 2015 – 2020 period. Discussion: Chlorpyrifos residue in vegetables can be reduced by washing, soaking brine, and boiling. The usage of rhodamine B on Terasi can be replaced by the application of dragon fruit skin extract and angkak (red yeast rice) for natural dye alternatives. Conclusion: Washing food with running water and soaking it in hot water before food consumption can lower chlorpyrifos residue level in dark vegetables. However, it is more significant to lover the residue level through the boiling step. The use of natural pesticides can be used as the choice of alternative. Moreover, rhodamine B on terasi can be replaced with natural dye alternatives such as angkak (red yeast rice) and dragon fruit skin extract.

Trong bài báo này, vật liệu quang xúc tác Cu2O/TiO2/rGO đã được tổng hợp bằng phương pháp thuỷ nhiệt. Các mẫu tổng hợp được đặc trưng bằng các phương pháp nhiễu xạ tia X (XRD), hồng ngoại (FT−IR), năng lượng tán xạ tia X (EDX), hiển vi điện tử truyền qua (TEM), UV−Vis rắn và đẳng nhiệt hấp phụ − khử hấp phụ nitơ. Kết quả cho thấy graphen oxit với các nhóm chức chứa oxy đã được tổng hợp thành công từ graphit. Các hạt nano TiO2 dạng anatat và Cu2O đã được phân tán lên các tấm graphen oxit dạng khử (rGO). Diện tích bề mặt riêng của vật liệu giảm khi các hạt nano oxit phân tán lên các tấm rGO và năng lượng vùng cấm của vật liệu tổng hợp giảm so với năng lượng vùng cấm của TiO2. Vật liệu Cu2O/TiO2/rGO thể hiện hoạt tính quang xúc tác cao trong phản ứng phân huỷ rhodamin B dưới tác dụng của ánh sáng khả kiến.

Rhodamin B is a green powder synthetic dye used as a textile dye and is often used to color a food product, especially tomato sauce. Tomato sauce sampled in Samarinda Morning Market for 5 samples. This research used color reaction test and KLT method. The result of the research using color reaction test showed that the sample did not contain rhodamine synthetic dye B. The result of identification with thin layer chromatography obtained Rf value of A sample 0,46, sample B 0,46, sample C 0,4, sample D 0,5 and sample E 0.78, the value of Rf standard rhodamin B 0.8. From the value of Rf, the sample E contains rhodamine B because the color of the sample spots and rhodamin B are the same pink and the difference of Rf value is in the range ± 0.02 of the standard Rf.

A series of novel organic-inorganic hybrid layered materials NiO/ZnNiCr-SalenNi-LDHs containing three different nickel components were prepared by facile coprecipitation. The above LDHs-based materials were characterized by XRD, SEM, TEM, FT-IR, UV–Vis DRS, XPS and XRF, and these results indicate that the different Ni components are located in the layers, intercalated between the layers and sported on the surface of the LDHs materials. The effects of different Ni components on the photocatalytic properties of the materials were investigated, and the regenerative ability of the hybrid material with the highest photocatalytic activity was explored. The introduce of Ni2+, SalenNi and NiO can affect the photocatalytic properties of the hybrid materials, in which SalenNi has the greatest effect on the photocatalytic performance of the hybrid materials. The material prepared under molar ratio conditions of Zn(NO 3) 2 ·6H 2 O: Ni(NO 3) 2 ·6H 2 O: Cr(NO 3) 3 ·9H 2 O = 3 : 1: 1, SalenNi: Cr(NO 3) 3 ·9H 2 O = 1 : 1, NiO: Cr(NO 3) 3 ·9H 2 O = 0.75 : 1 shows the strongest photocatalytic performance, and the degradation rate of Rhodamin B (RhB) can reach 93.8%. Meanwhile, this hybrid material has strong stability and high recycling efficiency. In addition, the photoactive species quenching experiments indicate that •O 2 − and h VB + are the main active species in the photocatalytic degradation of RhB. [Display omitted] • A organic-inorganic hybrid NiO/ZnNiCr-SalenNi-LDHs containing three different nickels were prepared. • Nis are located in the layers, between the layers and on the surface of the LDHs materials. • The introduce of Ni2+, SalenNi and NiO can affect the photocatalytic properties of the hybrid materials. • The degradation rate of RhB by NiO/ZnNiCr-SalenNi-LDHs is as high as 93.8%. • O 2 − and h VB + were the main active species in the photocatalytic degradation of RhB [ABSTRACT FROM AUTHOR]

Chili sauce is one of the most popular food product because it was used as food complement. Generally in processing manufacture chili sauce added coloring substance, so product colour interesting. Nowadays more and more food manufacturers use dye that have been banned use. Rhodamine B dye in the form of a crystalline powder green or reddish purple, odorless and dissolves easily in bright red solution berfluoresan as textile dyes. Rhodamin b is still no food products were found to countain rhodamine B dye such as crackers, sauces, ice and other pastries. Rhodamin B is a synthetic dye that was banned for use in foods and is certified as a hazardous material according to Minister of Healthy of Indonesian Republic No. 722/Menkes/Per/IX/1998. Rhodamin B is carcinogenic, in the long term use can cause liver damage, kidney inflammation, and cancer. The kind of research this used a quantitative approach with the experimental methods laboratory. The purpose of this study was to determine whether there rhodamin B in the test samples using thin layer chromatography (TLC). The result shows that 7 examined samples doesn’t contain rhodamin B and and shows f count smaller than f table (F count< F table) (3,61< 3,71). Synthetic dyes are contained in most of the analyzed samples are dyes that allow its use for food by the Regulation of the Minister of Health of Indonesia such as ponceau 4R and amarant and Contribution of research given by researchers of worksheets students and implementation plan learning

Rhodamin B merupakan salah satu zat warna yang umumnya banyak digunakan pada proses industri tekstil di Indonesia dan menghasilkan limbah cair yang mencemari lingkungan. Bentonit alam adalah material berpori yang kelimpahannya cukup banyak di alam dan dapat menangani masalah limbah cair melalui proses adsorpsi. Namun kapasitas bentonite dalam mengadsorpsi terbatas sehingga diperlukan modifikasi agar kemampuan adsorpsinya meningkat. Proses aktivasi menggunakan asam klorida dan pilarisasi menggunakan pemilar Al dan Cr digunakan sebagai cara untuk memodifikasi bentonit, sehingga diharapkan menghasilkan luas permukaan yang lebih besar. Hasil GSA pada montmorillonit teraktivasi menunjukkan basal spacing sebesar 15,68 Å dan luas permukaan sebesar 75,312 m2/g. Pemilaran menghasilkan montmorillonit terpilar Al25Cr75 dengan basal spacing paling tinggi dan luas permukaan secara berturut-turut sebesar 16,55 Å dan 41,804 m2/g. Adsorpsi rhodamin B menggunakan montmorillonit terpilar Al25Cr75 menghasilkan efektivitas adsorpsi sebesar 99,85% dari konsentrasi rhodamin B sebesar 50 ppm dengan kondisi optimum massa adsorben sebesar 0,1 gram dan waktu adsorpsi selama 75 menit, yang dianalisis menggunakan spektrofotometri UV-Vis pada panjang gelombang 523 nm.

In this study, the fabrication of ZnAl2O4/reduced graphene oxide nanocomposites is reported for the initial time. Two nanocomposites, ZnAl2O4/reduced graphene oxide‐50 and ZnAl2O4/reduced graphene oxide‐100, with different reduced graphene oxide contents (50 mg/ml and 100 mg/ml initial graphene oxide concentration respectively) were synthesized via a hydrothermal route; and characterized with the aid of suitable characterization and analytical techniques. For comparative purposes, two pure ZnAl2O4 samples were fabricated by citrate sol‐gel and urea combustion methods. The photocatalytic activity of the synthesized pure nanospinels and nanocomposites was studied for the degradation of rhodamine B dye under ultraviolet–A light irradiation. Compared to pure ZnAl2O4 nanoparticles, ZnAl2O4/reduced graphene oxide nanocomposites exhibited superior photocatalytic activity. The highest efficiency was observed for ZnAl2O4/reduced graphene oxide‐100 composite, where; full degradation of rhodamine B occurred after 45 min. The enhancements of the photocatalytic performance of ZnAl2O4/reduced graphene oxide composites were mainly attributed to unique electronic and surface properties of reduced graphene oxide. [ABSTRACT FROM AUTHOR]

[Display omitted] • Compositing nanoparticles can increase photocatalytic activity. • Nanocomposite ZnO/ZnMoO 4 was syntesized by insitu nanomaterial fabrication using MPLE. • ZnO has a good photocatalytic activity under visible light by compositing ZnMoO 4. • Mentha × piperita supports hydrothermal green synthesis process. • ZnO/ZnMoO 4 very good photocatalytic activity compared to ZnMoO 4 and ZnO. ZnO has excellent photocatalytic activity under UV light, but its photocatalytic activity under visible light is relatively low due to its wide band gap. Modification of ZnO to a composite with ZnMoO 4 , which has a band gap energy of 2.61 eV, triggers heterojunction photocatalytic reactions under visible light. Here in this research, ZnO-ZnMoO 4 nanocomposites have been successfully synthesized using the green synthesis hydrothermal method with Mentha × piperita leaf extract containing alkaloids as a source of weak bases and other secondary metabolites as capping agents. The development of green synthesis methods in this study aims to reduce the use of hazardous and toxic materials. The synthesized photocatalysts have been fully characterized and evidence of increased photocatalytic activity of ZnO/ZnMoO 4 composites is based on the degradation of Rhodamine B (RhB) dye in visible light. The results showed that the degradation of RhB by ZnO/ZnMoO 4 nanocomposites could reach 83.7 %, and this was better than using ZnO which only reached 13.9 %. [ABSTRACT FROM AUTHOR]

Summary: The kinetics of UV/H2O2 initiated degradation of organic compounds is demonstrated clearly by the use of colored water. The rate of decoloration of an aqueous solution of Rhodamine B initiated by UV irradiation in the presence of hydrogen peroxide is reactor‐specific. It depends not only on the power of the UV lamp, but also on the volume flow rate and the concentrations of RhB and of H2O2. Thus, we demonstrate the optimization of photoreactors for the UV initiated oxidation of water contaminants by use of colored aqueous solutions under variation of essential process parameters. The specified procedure may be performed with all kinds of commercially available photoreactors. Obviously, microphotoreactors described by Coyle and Oelgemoeller [7] are ideally suited for educational purposes. The safety precautions for the operation of UV photoractors must be followed. In addition, solar AOPs, e.g. Titaniumdioxide photocatalysis, may be illustrated. [ABSTRACT FROM AUTHOR]

Purpose The aim of this paper is to synthesize graphene-modified titanium dioxide (GR-TiO2) nanorod arrays nanocomposite films, so that these can enhance the photocatalytic properties of titanium dioxide and overcome the problem of difficult separation and recovery of photocatalysts.Design/methodology/approach The GR-TiO2 nanocomposite films were synthesized via hydrothermal method and spin-coating. The obtained samples were characterized by X-ray diffraction (XRD), scanning electron microscope (SEM), ultraviolet–visible (UV-Vis) diffuse reflectance spectrum and Raman spectrum. The photocatalytic performance of the GR-TiO2 nanocomposite films for degrading Rhodamin B under ultraviolet (UV) was studied by a UV-Vis spectrophotometer. The photocatalytic enhancement mechanism of graphene was studied by photoelectrochemical analysis.Findings The introduction of graphene expanded the range of the optical response of TiO2 nanorod arrays, improving the separation efficiency of the photogenerated electron-hole pairs, and thus dramatically increasing its photocatalytic performance.Research limitations/implications A simple and novel way for synthesizing GR-TiO2 nanocomposite films has enhanced the photocatalytic performance of TiO2.Originality/value The photocatalyst synthesized is easy to separate and recycle in the process of photocatalytic reaction, so it is possible to achieve industrialization. [ABSTRACT FROM AUTHOR]

Copper(II) Schiff-base Complexes (Salen-Cu(II)) intercalated zinc-chromium layered double hydroxides (ZnSBCuCr-LDHs) were successfully prepared via coprecipitation. Then, a novel photocatalytic material Zn-Cu-Cr composite oxides (ZnSBCuCr-MO) was prepared after calcination at 500 °C with ZnSBCuCr-LDHs as precursor. The structure and properties of the materials were thoroughly characterized by powder X-ray diffraction (XRD), inductively coupled plasma atomic emission spectrometry (ICP-AES), ultraviolet visible diffuse reflectance spectroscopy (UV-Vis DRS), scanning electron microscopy (SEM) and X-ray photoelectron spectroscopy (XPS). The photocatalytic activities of the materials were investigated by photodegradation of a cationic dye Rhodamin B (RhB), which was hard to adsorb by LDHs. The effects of the photocatalyst dosage, the initial pH and temperature of RhB solution on the photocatalytic efficiency were discussed. The results showed that ZnSBCuCr-MO displayed higher photocatalytic activity for RhB than calcined ZnCr-LDHs (ZnCr-MO) and calcined ZnCuCr-LDHs (ZnCuCr-MO). Meanwhile, ZnSBCuCr-MO exhibited better stability and reusability. In addition, the possible photocatalytic mechanism and degradation pathway for RhB were studied through density functional theory (DFT) calculation of the RhB molecule, UV-vis absorption variation and LC-MS analyses of the RhB solution. [ABSTRACT FROM AUTHOR]

The presence of carcinogenic dye like rhodamine B (Rh-B) in textile wastewater affects the quality of water to consumers. The adsorption of Rh-B on used black tea leaves (UBTL) was studied in batch process to investigate its removal efficiency. The effects of contact time, concentration, temperature, pH etc. on adsorption have been investigated. The UV-visible spectrophotometer was used for analysis of Rh-B at constant pH. The adsorption isotherms were constructed for different temperatures using acidic solution of pH 2.0. Freundlich, Langmuir and Dubinin–Raduskevich (D-R) equations were used to analyze the equilibrium adsorption data. The experimental data follows Freundlich equation more precisely compare with the Langmuir one. The maximum amount adsorbed calculated from Langmuir equation is 72.5 mg/g at 30 oC which is increased with increasing temperature. Separation factor and thermodynamic parameters revealed that the process is favorable, spontaneous and endothermic nature. Possible mechanism of the process was elucidated from the effect of solution pH on amount adsorbed. The endothermic nature of the adsorption might be due to the fragmentation of Rh-B molecules during the adsorption process.

The reaction of hydrogen peroxide and pheny -9-acridinecarboxylate in the presence of rhodamin B as a fluorophore leads to the emission of either bright blue light or bright red light, depending on the structure of fluorescer and reaction conditions. The light emitter responsible for the Chemi Luminescence (CL) reaction is acridone and that the blue light produced with out the fluorescers is a result of direct CL. The intensity and kinetic parameters for the CL systems were evaluated from fitting of the resulting intensity-time plots. The CL systems were investigated as concentration dependent of fluorescer, hydrogen peroxide, acridinium ester and sodium hydroxide as a catalyst.

Red chilli is an important food ingredient which may not be always safe, when obtained from the market. The aims of the study was to evaluate the safety and shelflife of red chilli paste. Based on survey conducted with 20 vendors in Bogor,we found red chilli paste is generally composed of red chilli, water, and NaCl. About 75% of the vendors claimed that the red chilli paste not sold in the first market day is stored in a plastic container at room temperature and resold for the next day. They claimed that their red chilli paste can be stored for 2-8 days. The red chilli paste showed moisture content of 71.6-86.8% (w/wb), pH 4.7-5.6, and NaCl 4.7-6.9% (w/w). About 33.3% of them positively contained exessive amount of sodium benzoate and 36% of them contained Rhodamin B which is prohibited as food colouring. From the microbiological side, the red chilli paste contained 9.5x103 - 3.8 x 105 cfu/g mould and yeast; 1.2 x 103 - 5.6 x 104 cfu/g spore forming bacteria; 5.2 x 102 - 1.2 x 104 cfu/g S. aureus;

The photocatalyst In 2 O 3 /AgBr/Bi 2 WO 6 with visible light response was synthesized using microwave-assisted hydrothermal method. The crystal structure, optical properties and surface morphologies of the products were characterized by XRD, UV–vis/DRS, SEM, TEM, HRTEM, XPS and N 2 adsorption–desorption tests. The results indicate that indium exists in the form of oxide and inhibits the growth of Bi 2 WO 6 at (1 3 3) crystal plane. The In 2 O 3 /AgBr/Bi 2 WO 6 composite consists of the particles piled up into flower-like spherical structures. In 2 O 3 /AgBr/Bi 2 WO 6 exhibits high photocatalytic activity for the Rhodamin B (RhB) degradation under ultraviolet and visible light, and, also, shows steady photocatalytic performance after four times of recycling. Besides, the potential photocatalytic mechanism of In 2 O 3 /AgBr/Bi 2 WO 6 was proposed according to the energy band structure of the composite, and the vital role of multi-pathway photogenerated electron migration during photocatalysis process was explained. [ABSTRACT FROM AUTHOR]

The single crystal of M-4-B was obtained by attaching the boron of BH3 to the amine linker between a tetraphenylethylene (TPE) unit and rhodamine B. M-4-B showed a novel sequential tricolor switching from dark blue to bluish-green and to a reddish color upon grinding. The boron atom played a key role in developing the single crystal. [ABSTRACT FROM AUTHOR]

The H3PW12O40@C photocatalysts synthesized in situ from dodetungstophosphoric acid (TPA) and soluble starch were studied and characterized by FTIR, XRD, scanning electron microscope, and energy dispersive X-ray analysis. The degradation of rhodamine B (RhB) wastewater with H3PW12O40@C photocatalysts and hydrogen peroxide was investigated under ultraviolet irradiation. The effect of different factors and synergetic effect on the degradation of RhB were studied and the mechanism of catalytic oxidation of RhB was discussed. The results showed that the RhB was degraded efficiently. The decoloration efficiency of the RhB was up to 94.6% with initial pH value of 6 and RhB concentration of 100 mg/L under better reaction conditions (i.e. hydrogen peroxide concentration of 12 mM, PW30 (represented raw materials formula according to weight ratio of TPA to soluble starch is 30%) mass of 1.0 g/L, reaction temperature of 25°C, the high pressure mercury lamp power of 500 W, and the radiation time of 70 min). Degradation process of RhB wastewater by ultraviolet, hydrogen peroxide, and PW30 has synergetic effect. [ABSTRACT FROM AUTHOR]

Warna merupakan faktor yang dapat digunakan sebagai indikator kesegaran atau kematangan suatuproduk. Warna merupakan daya tarik terbesar untuk menikmati aroma makanan. Warna dalammakanan dapat meningkatkan penerimaan konsumen tentang sebuah produk. Namun, penggunaanpewarna sintetis harus dilakukan sesuai dengan peraturan yang berlaku karena dapat merugikankesehatan. Oleh karena itu perlu dilakukan monitoring pewarna sintetis berbagai produk makananyang dikonsumsi oleh masyarakat. Metode analisis kualitatif yang digunakan adalah kromatografikertas. Sementara analisis kuantitatif menggunakan spektrofotometer UV-VIS. Pewarna sintetis yangterkandung dalam sebagian besar sampel yang dianalisis adalah pewarna yang memungkinkanpenggunaannya untuk makanan oleh Peraturan Menteri Kesehatan RI seperti sunset yellow, ponceau4R, tartrazine, dan carmoisin. Namun sampel krupuk pati mengandung zat yag dilarang yaituRhodamin B dengan konsentrasi 2,1892 ppm. Sampel mengandung zat pewarna campuran dari duaatau tiga jenis warna tunggal seperti es limun botol/orange (Amaranth,Tartrazine dan KuningFCF/Sunset Yellow) dan sampel permen merah (Ponceau 4R, Kuning FCF). Namun sebagian besarberupa pewarna tunggal. Pewarna sintetik yang ada dalam sampel permen kuning sebesar 22,642ppm dan 9,0119 ppm pada mie basah.

The presence of carcinogenic dye like rhodamine B (Rh-B) in textile wastewater affects the quality of water to consumers. The adsorption of Rh-B on used black tea leaves (UBTL) was studied in batch process to investigate its removal efficiency. The effects of contact time, concentration, temperature, pH etc. on adsorption have been investigated. The UV-visible spectrophotometer was used for analysis of Rh-B at constant pH. The adsorption isotherms were constructed for different temperatures using acidic solution of pH 2.0. Freundlich, Langmuir and Dubinin-Raduskevich (D-R) equations were used to analyze the equilibrium adsorption data. The experimental data follows Freundlich equation more precisely compare with the Langmuir one. The maximum amount adsorbed calculated from Langmuir equation is 72.5 mg/g at 30 °C which is increased with increasing temperature. Separation factor and thermodynamic parameters revealed that the process is favorable, spontaneous and endothermic nature. Possible mechanism of the process was elucidated from the effect of solution pH on amount adsorbed. The endothermic nature of the adsorption might be due to the fragmentation of Rh-B molecules during the adsorption process. [ABSTRACT FROM AUTHOR]

Abstract: A nanocomposite, D201-CdS, made by depositing CdS nanoparticles on a resin support (D201) was found to be a promising photocatalyst with visible light response. To elucidate the structure-activity relationship, a set of D201-CdS nanocomposites varying in CdS amount and distribution were prepared by adjusting the concentration of sulfide anion and the precipitation time. The maximum compressive strength of the nanocomposites increased first with the loading of CdS and then declined with the further increase of CdS. There was a valid shell thickness of CdS due to the limitation of visible light in penetration through the resin matrix. Within a certain range of shell thickness, the increase of shell density of CdS would be favorable for the purpose of photodegradation. The shell density could be easily tuned by adjusting the fabrication condition employed in this work, which is an important merit for the potential production and application. [Copyright &y& Elsevier]

Abstract: The nanoparticulate carrier systems solid lipid nanoparticles (SLN) and dendritic core-multishell (CMS) nanotransporters gained interest for the topical treatment of skin diseases as they facilitate the skin penetration of loaded lipophilic drugs. Here, we studied if these carrier systems are also suitable drug delivery systems for more hydrophilic agents using the dye rhodamin B as model compound. Furthermore, the influence of the particle size on the skin penetration was investigated. Loading rhodamin B onto SLN (250–340nm) and CMS nanotransporters (20–30nm), the dye amount increased significantly in viable epidermis and dermis as compared to a conventional cream. CMS nanotransporters were most efficient. Creating nanoparticles of 50–200nm demonstrated only marginal size effect for the skin penetration. Therefore, the superiority of the CMS nanotransporters seems to be attributed to the character of the nanoparticles and not to its smaller size. [Copyright &y& Elsevier]

Abstract: Bismuth vanadate (BiVO4) powders were synthesized by homogeneous precipitation method with different surface dispersants. Bi(NO3)3·5H2O and NH4VO3 were utilized as starting materials to synthesize BiVO4 particles with the edge length of about 100–150nm. Bismuth oxide (Bi2O3) was prepared by decomposing Bi(NO3)3·5H2O at 600°C. Techniques of X-ray diffraction (XRD), scanning electron microscope (SEM), transmission electron microscope (TEM) and ultraviolet–visible diffuse reflectance spectra (UV–vis DRS) have been employed to characterize the as-synthesized materials. The results showed that the structure and morphology of BiVO4 were various using different surface dispersant. We have also investigated the photocatalytic degradation of rhodamin B which showed that BiVO4/Bi2O3 possessed a high photocatalytic activity under visible-light irradiation. The photocatalytic activity is in close relation with the surface dispersant about BiVO4 synthesis. The result was better using N,N-dimethylacetamide (DMA) than using N-methyl-2-pyrrolidone. The inverse proportion between BiVO4 and Bi2O3 was also important for the photocatalysis. [Copyright &y& Elsevier]

A flow injection chemiluminescence method has been developed and applied to the determination of hemin in tablets and animal blood. The proposed method is based on the luminescent properties of the Rhodamine B-H2O2-NaOH system and the addition of sodium dodecyl sulfonate (SDS) as emission-sensitizer. Hemin was determined over the concentration range of 8.6×10-10-8.6×10-7?M with a detection limit of 8.6×10-11?M (3s). The relative standard deviation (RSD) for seven independent detections of 1.72×10-8?M hemin was 3.0%. The proposed method was successfully applied to the analysis of hemin in pharmaceutical preparations and animal blood with a recovery of 96-108%. A possible CL mechanism of the present system was discussed, and free radicals were suggested to be involved in this reaction. [ABSTRACT FROM AUTHOR]

A novel chemiluminescence system for the determination of bismerthiazol is first described in this paper. It is based on the chemiluminescence reaction of bismerthiazol and Ce(IV) in nitric acid solution. The emission intensity could be enhanced greatly by Rhodamine B. The chemiluminescence intensity was proportional to bismerthiazol concentration over the range 30–1000 μg/L. The detection limit was 12 μg/L (3 σ) and the relative standard deviation is 2.4% for 500 μg/L of bismerthiazol ( n = 11). The proposed method was successfully applied to the determination of bismerthiazol in water and in rice. The recovery was 96.4%–104.1%. [ABSTRACT FROM AUTHOR]