Catalysts
·
2020
·Vol. 10
·期 5
·575
·
IF 3.52
Luqian Zhang,Chen Wang,Jing Sun,Zhengkai An
Benzene is a typical volatile organic compound (VOC) and is found widely in industrial waste gases. In this study, trimesoyl chloride-melamine copolymer (TMP)-TiO2nanocomposites with excellent photocatalytic efficiency in visible-light degradation of gas-phase benzene were synthesized via an in situ hydrothermal synthesis. The optimal conditions for TMP-TiO2nanocomposite synthesis were determined by orthogonal experiments. The structural, physiochemical, and optoelectronic properties of the samples were studied by various analytical techniques. Ultraviolet-visible diffuse reflectance spectroscopy and surface photovoltage spectra showed that the positions of the light-absorbance edges of the TMP-TiO2nanocomposites were sharply red-shifted to the visible region relative to those of unmodified TiO2. The most efficient TMP-TiO2nanocomposite was used for photocatalytic oxidative degradation of gas-phase benzene (initial concentration 230 mg m−3) under visible-light irradiation (380–800 nm); the degradation rate was 100% within 180 min. Under the same reaction conditions, the degradation rates of unmodified TiO2(hydrothermally synthesized TiO2) and commercial material Degussa P25 were 19% and 23.6%, respectively. This is because the Ti–O–N and Ti–O–C bonds in TMP-modified TiO2reduce the band gap of TMP-TiO2. The amide bonds in the TMP decrease the TiO2nanoparticle size and thus increased the specific surface area. The conjugated structures in the TMP provide abundant active sites for trapping photogenerated electrons and promote the separation and transfer of photogenerated electrons and holes.Keywords:TiO2;visible light;volatile organic compound;benzene;gas degradation
研究领域:
材料科学
·
环境科学
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DOI
高影响因子
Toxics
·
2023
·Vol. 11
·期 9
·799
·
IF 4.6
Hangwei Wang,Zhanren Liu,Shaojie Liu,Ruoru Yang,Yifei Wang,Yiying Gu,Min Wu,Ruihua Dong,Bo Chen
This study aimed to assess the therapeutic efficacy of catechin against experimentally induced kidney stones resulting from co-exposure to melamine (MEL) and cyanuric acid (CYA) in male Sprague–Dawley rats. To induce nephrolithiasis, a combination of MEL and CYA (1:1 ratio, each at a dose of 31.5 mg/kg bw/day) was administered to the rats for 28 consecutive days. After nephrolithiasis was successfully induced, the rats were randomly divided into two groups: a treatment group and a sham group. The treatment group was given a daily oral dose of 50 mg/kg of catechin for 28 days, while the sham group received no intervention. Urine and blood samples were collected throughout the treatment period, and kidney samples were taken on day 28. Our findings demonstrated that treatment with catechin significantly reduced crystal deposition and pathological damage in the rats from nephrolithiasis. Additionally, renal injury markers were significantly decreased in the treatment group compared to the sham group. These findings suggest that catechin has potential therapeutic benefits in treating nephrolithiasis induced by co-exposure to MEL and CYA.Keywords:melamine;cyanuric acid;nephrolithiasis;catechin
研究领域:
毒理学
·
药理学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
LWT-FOOD SCIENCE AND TECHNOLOGY
·
2012
·
IF 2.545
Wei Feng,Changyin Lv,Liping Yang,Jianlin Cheng,Chengyan Yan
Melamine, a basic organic chemical intermediate, can cause renal failure because of the formation of insoluble melamine cyanurate crystals in the kidneys. This study examined a novel fluorescence spectrometry for the determination of trace melamine in dairy. The method was based on the inhibitory effect of melamine on the decolorizing reaction of the uncatalytic oxidation of acridine red by potassium permanganate in a sulfuric acid medium. The calibration graph was linear for melamine concentrations of 2.1 × 10 −4 –1.6 mg/L, and a detection limit of 61.5 ng/L was obtained. The melamine was determined in dairy samples by the proposed method after liquid–liquid and solid phase extraction. The results correlated with the high-performance liquid chromatography. The recoveries were within the range of 99.6–103.3% for liquid milk and 98.5–111.1% for milk powder. The possible mechanism of the reaction was also investigated by ultraviolet spectra.
研究领域:
分析化学
·
食品安全
·
生物医学
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产品关联
DOI
高影响因子
NEW JOURNAL OF CHEMISTRY
·
2017
·Vol. 41
·期 16
·7924-7931
·
IF 3.269
Aiping Gao,Yiran Li,Haiting Lv,Dan Liu,Na Zhao,Qianqian Ding,Xinhua Cao
In this study, a new gelator containing lenalidomide and cholesterol groups was synthesized, which could form stable gels in 1,4-dioxane and mixed solvents of DMF/H2O (v/v, 1/1). The self-assembly process was studied and certified by field emission scanning electron microscopy, UV-vis, IR, XRD, and CA. Based on the results obtained from the abovementioned analyses, the self-assembly structure, aggregation pattern, and surface wettability could be tuned via the addition of melamine due to intermolecular hydrogen bonding between compound 1 and melamine (MA). The irregular lumpy and the closely packed fiber structures could be turned into microbelt and sparse fiber structures after the addition of MA, respectively. Moreover, the hydrophobicity of the xerogel film of 1-MA was obviously increased. The mechanical strength of gel 1-MA was obvisously enhanced due to the addition of MA. The UV-vis, IR, and XRD experiment results showed that the self-assembly process and mode of 1 was changed due to the addition of MA through intermolecular hydrogen bonding between 1 and MA. Therefore, these results provide a method for the regulation of the self-assembly process via intermolecular noncovalent interaction.
研究领域:
化学
·
材料科学
·
生物医学
✓ 已验证
DOI
高影响因子
RSC Advances
·
2015
·Vol. 5
·期 47
·37697-37702
·
IF 3.84
Liuyi Yin,Yufeng Hu,Xianming Zhang,Jianguang Qi,Weiting Ma
Batch reaction experiments were performed to investigate the salt effect on the yield of trioxane in the reaction solution. The salts considered include NaHSO4, Na2SO4, NaH2PO4, Na2HPO4, KCl, NaCl, LiCl, ZnCl2, MgCl2, and FeCl3. The effects of the anionic structure and the cation charge density on the yield of trioxane in the reaction solution were elucidated and the mechanisms that govern such effects were established. It is shown that the first four salts exerted a negative effect on the yield of trioxane in the reaction solution and such an effect increased progressively from left to right. This trend is due to the formation of NaHSO4, H3PO4, or (H3PO4 and NaH2PO4), which decreased the concentration of H+ in the solution. The latter six salts showed a positive effect on the yield of trioxane in the reaction solution. The salt effect paralleled the ability of the salt to decrease the water activity of the reaction solution and followed the order KCl < NaCl < LiCl < ZnCl2 < MgCl2 < FeCl3. Continuous production experiments were performed to investigate the salt effect on the concentration of trioxane in the distillate. The salts considered were KCl, NaCl, LiCl, ZnCl2, MgCl2, and FeCl3, and the salt effect increased progressively from left to right. Such an effect was shown to be determined by the ability of the salt to increase the yield of trioxane in the reaction solution and to increase the relative volatilities of trioxane and water and of trioxane and oligomers.
研究领域:
化学工程
·
工业化学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF FOOD PROCESS ENGINEERING
·
2018
·Vol. 42
·期 2
·e12976
·
IF 1.955
Ning Yang,Liang-Liang Xie,Chen Pan,Min-Feng Yuan,Zhi-Han Tao,Han-Ping Mao
Ubiquitous food security control is desirable. However, the analysis methods, such as those for milk, are highly based on manual analysis, leading to low efficiency. Thus, we report a multilayer paper-based microfluidic chip transforming chromatic readout to electric signals. First, colloidal gold immunochromatographic assays (GICA) are used to achieve the colorimetric occurrence. Secondly, the test (T) lines and control (C) lines are patterned to encode different EAN-8 barcode. Furthermore, accurate scanning is accomplished by the automatic threshold segmentation. These technologies make the digital determination of melamine (MEL) and chloramphenicol (CAP) by phone readily accessible. Results indicate that the accurate machine-scanning can be assured when MEL and CAP is above 30 ng/mL and 6 ng/mL in milk respectively. The detection time is under 8 min, and the stable storage life is over 90 days. Therefore, this simple chip allows rapid, machine-readable, electric-recordable diagnostic directly from chromatic assays with satisfying stability, specificity and accuracy. Practical applications This article illustrates a method used to determine the concentration of melamine and chloramphenicol in milk. When melamine and chloramphenicol is above 30 and 6 ng/ml in milk, the produced EAN-8 barcode can be recognized with high accurate level, compared with international standards, the results are acceptable and sensitive. This method is highly intellectual and environmentally friendly, with the disposable materials and instant smartphone-readable EAN-8 results patterns. This article demonstrates a multilayer paper chip based on EAN-8 encoding rules, colloidal gold nanoparticles, and immunochromatographic assays. The EAN-8 format assay is achieved by color-development occurrence of colloidal GICA in different encoding areas of EAN-8 code, and the analysis device, namely smartphone, is accessible by almost every individual. Therefore, this chip can pave a potential way for massive health control and digital automated analysis for daily life and industrial manufacture.
研究领域:
食品安全
·
分析化学
·
生物医学工程
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF COLLOID AND INTERFACE SCIENCE
·
2015
·
IF 3.368
Ling Zhu,Guanhong Xu,Fangdi Wei,Jing Yang,Qin Hu
A novel molecularly imprinted stir bar (MIP-SB) was developed with melamine (MA) as the template molecule in this study. The sorptive capacity of MIP-SB was nearly three times over that of non-imprinted stir bar (NIP-SB). The MIP-SB presented much better selectivity than NIP-SB when used to absorb MA and its analogues. An analytical method to determine MA in powdered milk was established by combining MIP-SB sorptive extraction with HPLC. The liner range was 0.0631–12.6 ng/mL with good correlation coefficient of 0.9983, and the limit of detection was 0.0127 ng/mL based on three times ratio of signal to noise. This method was successfully applied to the determination of MA in powdered milk with satisfactory results. The method built is simple and suitable for the determination of MA in milk products which is of great significance for quality control of milk products.
研究领域:
分析化学
·
食品科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
JOURNAL OF COLLOID AND INTERFACE SCIENCE
·
2023
·
IF 9.9
Yonggan Ju,Jingxian Hua,Yawei Gu,Hongling Chen
Foams can be seen everywhere in human production and life. An uncontrolled foam event usually leads to product losses, equipment damage, and clean-up costs. Defoamer is one of the most effective strategies to eliminate or inhibit foam activities, which has been proved by long-term practices. In this work, we report new molecular defoamers with high-branched structure, which adopts melamine molecule as the parent structure, by incorporating alkyl-isocyanates with different chain lengths into the high-branched melamine derivatives (Hb-MDs) formula to replace the R − NH 2 (primary ammonia) on melamine structure. The substitution reaction processes can be readily tuned by varying the molar ratio or alkyl chain length of alkyl-isocyanate, enabling a facile control over the branched degree. The foam tests reveal that the high-branched melamine molecule defoamers exhibited excellent defoaming and anti-foaming properties for four typical foam systems, including an anionic SDBS , cationic DTAB , non-ionic AEO-9, and white cat (BM) detergent, with efficiency close to that of silicone-type LN1414 defoamer and far superior to that of high-carbon alcohol XS-02 defoamer, at the same addition level. Notably, the defoaming or anti-foaming performances of the high-branched melamine molecule defoamers were not always monotonically increased with the branched degree or hydrophobic chain length, but a suitable range needed to be maintained to support a good balance of defoamer structure with foam liquid films . Therefore, it is anticipated that this high-branched design principle could open a new avenue for the construction of molecular defoamers for complex industrial problems.
研究领域:
化学工程
·
材料科学
·
表面化学
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产品关联
DOI
PubMed
高影响因子
FOOD CONTROL
·
2018
·
IF 3.667
Xueqi Leng,Yuqin Tu,Yunping Wu,Yu Wang,Su Liu,Qianqian Pei,Xuejun Cui,Jiadong Huang
A fluorescence sensing strategy was described for the determination of melamine with ultrasensitivity and high specificity. This strategy relies on the combination of proximity ligation assay (PLA)-modulated thymine–melamine–thymine (T–melamine–T) triplex structure along with exonuclease III (Exo III)-aided recycling amplification. The reaction system involves three DNA probes (poly A, tDNA and molecular beacon (MB)). Probe ploy A is an adenine enriched sequence containing an apurinic/apyrimidinic site (AP site). It can provide a hydrophobic vacancy for specially recognizing melamine to bind the nucleobase through pseudo-base pairing and participate in PLA modulated T-melamine-T triplex structure. Probe tDNA can form T-melamine-T with probe poly A via PLA only in the presence of melamine. Probe MB is modified with a fluorophore at its 5′-terminus and a quencher at an internal position, which can self-hybridize to form a hairpin structure, positioning the fluorophore in close proximity to the quencher. Therefore, the binding of MB did not yield any fluorescence signal. However, in the presence of melamine, a T-melamine-T triplex structure is formed through PLA. Probe MB can hybridize with t T-melamine-T triplex structure to yield a substrate for interaction with Exo III. As a result, the T-melamine-T triplex structure is released. Next, the released T-melamine-T triplex structure will hybridize with another MB probe to achieve the Exo III-aided recycle amplification. This is the first example of PLA-modulated T-melamine-T triplex structure coupled with Exo III-aided recycling amplification. Under optimal conditions, the assay has a detection range over 4 orders of magnitude and a limit of detection of 4.4 nM. Moreover, the assay is rapid, simple and inexpensive. Hence, the strategy may open new avenues for ultrasensitive and highly specific detection of melamine encounted in food analysis .
研究领域:
分析化学
·
食品科学
·
分子生物学
✓ 已验证
产品关联
DOI
高影响因子
ACS Omega
·
2020
·
IF 2.87
Bo Gao,Gengxin Wang,Bao Li,Lixin Wu
To understand the self-inclusion and the dissociation in a branched β-cyclodextrin (CD) system, we designed and synthesized a β-CD trimer in which each CD group is connected to one of bridging arms of a planar triphenylbenzene core through a CuAAC click reaction. Only one rather than two or all of the three host CDs was demonstrated to be in a self-including state in water, while no self-inclusion was observed to occur in dimethylsulfoxide (DMSO) via the characterization of 1H and NOESY NMR spectra. The configuration structures of the CD groups in the self-included state were evaluated, and the dissociation to free state in water was investigated under various conditions like heating, increased acidity, and discharging versus the addition of competitive guests. While raised temperature and increased acidity did not break the self-inclusion, two adamantane guest molecules were found to show capability in driving the equilibrium to get back to free state against the self-inclusion. The inclusion process of the added guests was believed to involve in the dissociation of the self-inclusion and the occupation of the guests in CD cavity. The results of host–guest interaction study indicated that the stable combination of guests was favorable for blocking the structural overturning of glucose toward trapping the bridging group into the cavity.
研究领域:
化学
·
分子生物学
✓ 已验证
DOI
高影响因子
INTERNATIONAL JOURNAL OF BIOLOGICAL MACROMOLECULES
·
2024
·
IF 7.7
Siqi Quan,Jingting Zhang,Lanyue Zhang,Na Li,Lijun Zhu,Xiuxia Sun,Jianxi Xiao
Type IV collagen , a principal constituent of basement membranes , consists of six distinct α chains that assemble into both ABC and AAB-type heterotrimers. While collagen-like peptides have been investigated for heterotrimer formation, the construction of ABC-type heterotrimeric collagen mimetic peptides remains a formidable challenge, primarily due to the intricate composition and arrangement of the chains. We have herein for the first time reported the development of a versatile triblock peptide system to mimic ABC-type heterotrimeric collagen stabilized by salt bridges. The triblock peptides A, B, and C incorporate functional natural type IV collagen sequences in the center, along with charged amino acids at their N and C-terminals. By leveraging electrostatic repulsion at these charged termini, the formation of homotrimers is effectively inhibited, while stable ABC-type heterotrimers are generated through the establishment of salt bridges between oppositely charged terminals. Circular dichroism (CD) spectroscopy demonstrated that peptides A, B, and C existed as individual monomers , while they effectively formed stable ABC-type heterotrimers upon being mixed at a molar ratio of 1:1:1. Additionally, fluorescence quenching results indicated that fluorescence-labeled peptides A′, B′, and C′ formed ABC-type heterotrimer, exhibiting comparable thermal stability as determined by CD spectroscopy. Molecular dynamics simulations elucidated the role of salt bridges between arginine and aspartic acid residues at N- and C-terminals in maintaining a unique chain register in the ABC-type heterotrimers. These triblock peptides offer a robust approach for replicating the structural and functional characteristics of type IV collagen, with promising applications in elucidating the biological roles and pathologies associated with heterotrimeric collagen.
研究领域:
生物化学
·
分子生物学
·
材料科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Polymers
·
2024
·Vol. 16
·期 11
·1557
·
IF 4.7
An Wei,Shunxiang Wang,Yongjin Zou,Cuili Xiang,Fen Xu,Lixian Sun
To broaden the applications of wood, it is necessary to prepare flame-retardant coatings that can protect wood substrates during combustion. In this study, a bio-based, intumescent, flame-retardant phytic acid–melamine polyelectrolyte (PM) was prepared using phosphorus-rich biomass phytic acid and nitrogen-rich melamine as raw materials through an ion crosslinking reaction. Subsequently, a series of bio-based, flame-retardant wood coatings were prepared by optimizing the structure of urea–formaldehyde resin with the addition of melamine, sodium lignosulfonate, and PM as a flame-retardant curing agent. Woods coated with PM-containing coatings displayed significantly improved flame-retardant performances in comparison to uncoated woods. For PM-cured woods, the measured values of total heat release and total smoke production were 91.51% and 57.80% lower, respectively, compared with those of uncoated wood. Furthermore, the fire growth index decreased by 97.32%, indicating a lower fire hazard. This increase in flame retardancy and smoke suppression performance is due to the dense expanded carbon layer formed during the combustion of the coating, which isolates oxygen and heat. In addition, the mechanical properties of the flame-retardant coatings cured with PM are similar to those cured with a commercial curing agent, NH4Cl. In addition, the prepared flame-retardant coating can also stain the wood. This study proves the excellent flame-retarding and curing effect of ammonium phytate in urea–formaldehyde resin coatings and provides a new approach for the application of bio-based flame retardants in wood coatings.
研究领域:
材料科学
·
林业工程
·
生物质化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
危险品化学品经营许可证（带存储）