NiCoZn/C@melamine sponge-derived carbon composites with highperformance electromagnetic wave absorption

NiMZn/C@melamine sponge-derived carbon(MSDC)composites(M=Co,Fe,and Mn)were prepared by a vacuum pump-ing solution method followed by carbonization.A large number of carbon nanotubes(CNTs)homogeneously attached to the surfaces of the three-dimensional cross-linked of the sponge-derived carbon in the NiCoZn/C@MSDC composite,and CNTs were detected in the NiFeZn/C@MSDC and NiMnZn/C@MSDC composites.Ni_(3)ZnC_(0.7),Ni_(3)Fe,and MnO in-situ formed in the NiFeZn/C@MSDC and NiMnZn/C@MSDC composites.The CNTs in the NiCoZn/C@MSDC composite efficiently modulated its complex permittivity.Thus,the composite exhibited the best performance among the composites,with the minimum reflection loss(RL_(min))of-33.1 dB at 18 GHz and thickness of 1.4 mm.The bandwidth for RL of≤-10 dB was up to 5.04 GHz at the thickness of 1.7 mm and loading of 25wt%.The op-timized impedance matching,enhanced interfacial and dipole polarization,remarkable conduction loss,and multiple reflections and scat-tering of the incident microwaves improved the microwave absorption performance.The effects of Co,Ni,and Fe on the phase and mor-phology provided an alternative way for developing highly efficient and broadband microwave absorbers.

A Survey of Urolithiasis in Young Children Fed Infant Formula Contaminated with Melamine in Two Townships of Gansu,China

Objective To determine the prevalence of urolithiasis in young children fed infant formula（IF） contaminated with melamine,and the association between IF consumption and urolithiasis.Design A total of 2 733 children ≤3 years of age on September 1,2008 in two townships of Gansu Province,China were studied.Cases of urolithiasis were diagnosed by ultrasonography.Milk product consumption was determined by their caregivers.Remaining IF samples were tested for melamine and cyanuric acid.Results Of 2 733 eligible children in the two townships,2 186（80%） were enrolled in our study.Overall,16.6%（362） of 2 186 children had urolithiasis.The prevalence was 24.6% in children exclusively fed Sanlu brand IF,9.7% in those fed other IF,and 8.5% in those fed exclusively on other milk products.For children exclusively breast-fed,no urolithiasis was found（P0.05）.The prevalence of urolithiasis was 11.4% in children fed 400 g of Sanlu IF,rising to 37.5% in children fed over 25 600 g.Of 48 Sanlu IF samples,91.7% contained melamine（median=1 800 ppm;range=45-4 700） and 66.7% contained cyanuric acid（median=1.2 ppm;range=0.4-6.3）.Melamine was also detected in 22.2% of 36 other brand IF（median=27.5 ppm,range=4-50）.Conclusions Urolithiasis was associated with melamine-contaminated IF.Although one product caused most morbidity,other milk products may have also contributed to the outbreak.

An efficient and mild recycling of waste melamine formaldehyde foams by alkaline hydrolysis

Melamine formaldehyde foam(MFF)generates many poisonous chemicals through the traditional recycling methods for organic resin wastes.Herein,a high MFF degradation ratio of ca.97 wt.%was achieved under the mild conditions(160℃)in a NaOH–H2O system with ammelide and ammeline as the main degradation products.The alkaline solvent had an obvious corrosion effect for MFF,as indicated by scanning electron microscopy(SEM).The reaction process and products distribution were studied by Fourier-transform infrared spectroscopy(FTIR),X-ray photoelectron spectroscopy(XPS),and ^(13)C nuclear magnetic resonance(NMR).Besides,the MFF degradation products that have the similar chemical structures and bonding performances to those of melamine can be directly used as the raw material for synthesis of melamine urea-formaldehyde resins(MUFs).Moreover,the degradation system demonstrated here showed the high degradation efficiency after reusing for 7 times.The degradation process generated few harmful pollutants and no pre-or post-treatments were required,which proves its feasibility in the safe removal or recovery of waste MFF.

Ultrahydrophobic melamine sponge via interfacial modification with reduced graphene oxide/titanium dioxide nanocomposite and polydimethylsiloxane for oily wastewater treatment

Three-dimensional(3D)porous absorbents have attracted significant attention in the oily wastewater treatment technology due to their high porosity and elasticity.Given their amphiphilic surface,they have a propensity to simultaneously absorb water and oil,which restricts their range of applications.In this study,a reduced graphene oxide and titanium dioxide nanocomposite(rGO/TiO_(2))was used to fabricate an ultra-hydrophobic melamine sponge(MS)through interfacial modification using a solution immersion technique.To further modify it,poly-dimethylsiloxane(PDMS)was grafted onto its surface to establish stronger covalent bonds with the composite.The water contact angle of the sponge(rGO/TiO_(2)/PDMS/MS)was 164.2°,which satisfies the condition for ultrahydrophobicity.The evidence of its water repellency was demonstrated by the Cassie-Baxter theory and the lotus leaf effect.As a result of the increased density of rGO/TiO_(2)/PDMS/MS,it recorded an initial capacity that was 2 g/g lower than the raw MS for crude oil absorption.The raw MS retained 53% of its initial absorption capacity after 20 cycles of absorption,while rGO/TiO_(2)/PDMS/MS retained 97%,suggesting good recyclability.Excellent oil and organic solvent recovery(90%-96%)was demonstrated by rGO/TiO_(2)/PDMS/MS in oil-water combinations.In a continuous separation system,it achieved a remarkable separation efficiency of 2.4×10^(6)L/(m^(3)·h),and in turbulent emulsion separation,it achieved a demulsification efficiency of 90%-91%.This study provides a practical substitute for massive oil spill cleaning.

Facile SERS screening of melamine in bovine milk with 2D printed AgNPs/glass fabric filter paper as the flexible substrate

Melamine is one of the most frequently detected adulterants in dairy products.The current study proposes a surface-enhanced Raman spectroscopy(SERS)-based analytical tool for fast and reliable screening of melamine in bovine milk.A hand-held Raman spectrometer was used in conjunction with a substrate composed of silver nanoparticles(AgNPs)that was 2D printed onto glass fiber(GF)filter paper.Under optimized conditions,a sensitive and fingerprint-like signal at 674 cm^(-1) was obtained.The AgNPs/GF substrate exhibited high sensitivity to melamine in milk down to 1.9498×10^(-5)mg/mL,which is well below the USA and EU safety limits(2.5×10^(-3)mg/mL).Remarkably,the proposed technology was also highly reproducible,showing spot-to-spot and block-to-block variations below 3.3%and 4.9%at 674 cm^(-1) in Raman intensity,respectively.The characteristic peak intensity and concentration of melamine showed an acceptable linear relationship(R^(2)=0.9909)within the range of 0.0001-1 mg/mL.Overall,the method established in this study can provide an efficient and effective method for the quantitative target screening and detection of melamine in dairy products.

Characterization of Flame Retardancy and Oil-Water Separation Capacity of Superhydrophobic Silylated Melamine Sponges

A silylated melamine sponge(SMS)was prepared by two simple steps,namely,immersion and dehydration of a melamine sponge coated with methyltrichlorosilane.The silylated structure of SMS was characterized by FT-IR(Fourier-transform infrared)spectroscopy,SEM(Scanning electron microscopy)and in terms of water contact angles.Its oil-water absorption and separation capacities were measured by FT-IR and UV-visible spectrophoto-metry.The experimental results have shown that oligomeric silanol covalently bonds by Si-N onto the surface of melamine sponge skeletons.SMS has shown superhydrophobicity with a water contact angle exceeding 150°±1°,a better separation efficiency with regard to diesel oil(by 99.31%(wt/wt%)in oil-water mixture and even up to 99.99%(wt/wt%)for diesel oil in its saturated aqueous solution.Moreover,SMS inherited the intrinsicflame retardancy of the melamine sponge.In general,SMS has shown superhydrophobicity,high porosity,excellent selectivity,remarkable recyclability,and better absorption capacity for various oils and organic solvents,and a high separation efficiency for oil in saturated aqueous solutions.

Risk factors for congenital nasolacrimal duct obstruction in children under two years of age

·AIM:To identify various risk factors that may play a significant role in the development of congenital nasolacrimal duct obstruction(CNLDO).·METHODS:This observational case-control study included a case group of 122 children less than two years of age with CNLDO who underwent probing and irrigation treatment at the ophthalmology department of Imam Khomeini Hospital in Ahvaz,Iran,from June 2022 to June2024.A control group of 122 age-matched children without CNLDO was also included for comparison.Data was collected from the children's medical records.·RESULTS:The study found a significant correlation between the occurrence of CNLDO and several maternal factors,such as preeclampsia,the use of levothyroxine,hypothyroidism,having more than three pregnancies(gravidity>3),natural pregnancy,and gestational diabetes mellitus.Additionally,in children,factors,such as oxygen therapy,anemia,reflux,jaundice,and a family history of CNLDO in first-degree relatives were associated with CNLDO,and maternal preeclampsia and hypothyroidism were found to significantly increase the risk of developing CNLDO in children.·CONCLUSION:Given that CNLDO affects both premature and full-term children,the present findings may potentially facilitate the early identification of children and infants at risk of nasolacrimal duct obstruction,thereby preventing the onset of chronic dacryocystitis.

The effects of exercise interventions on brain-derived neurotrophic factor levels in children and adolescents:a meta-analysis

Brain-derived neurotrophic factor is a crucial neurotrophic factor that plays a significant role in brain health. Although the vast majority of meta-analyses have confirmed that exercise interventions can increase brain-derived neurotrophic factor levels in children and adolescents, the effects of specific types of exercise on brain-derived neurotrophic factor levels are still controversial. To address this issue, we used meta-analytic methods to quantitatively evaluate, analyze, and integrate relevant studies. Our goals were to formulate general conclusions regarding the use of exercise interventions, explore the physiological mechanisms by which exercise improves brain health and cognitive ability in children and adolescents, and provide a reliable foundation for follow-up research. We used the Pub Med, Web of Science, Science Direct, Springer, Wiley Online Library, Weipu, Wanfang, and China National Knowledge Infrastructure databases to search for randomized controlled trials examining the influences of exercise interventions on brain-derived neurotrophic factor levels in children and adolescents. The extracted data were analyzed using Review Manager 5.3. According to the inclusion criteria, we assessed randomized controlled trials in which the samples were mainly children and adolescents, and the outcome indicators were measured before and after the intervention. We excluded animal experiments, studies that lacked a control group, and those that did not report quantitative results. The mean difference(MD;before versus after intervention) was used to evaluate the effect of exercise on brain-derived neurotrophic factor levels in children and adolescents. Overall, 531 participants(60 children and 471 adolescents, 10.9–16.1 years) were included from 13 randomized controlled trials. Heterogeneity was evaluated using the Q statistic and I^(2) test provided by Review Manager software. The meta-analysis showed that there was no heterogeneity among the studies(P = 0.67, I^(2) = 0.00%). The combined effect of the interventions was significant(MD = 2.88, 95% CI: 1.53–4.22, P < 0.0001), indicating that the brain-derived neurotrophic factor levels of the children and adolescents in the exercise group were significantly higher than those in the control group. In conclusion, different types of exercise interventions significantly increased brain-derived neurotrophic factor levels in children and adolescents. However, because of the small sample size of this meta-analysis, more high-quality research is needed to verify our conclusions. This metaanalysis was registered at PROSPERO(registration ID: CRD42023439408).

Mycoplasma pneumoniae pneumonia in children

Mycoplasma pneumoniae(M.pneumoniae)is a common pathogen that causes community-acquired pneumonia in children.The clinical presentation of this pathogen can range from mild self-limiting illness to severe and refractory cases.Complications may occur,such as necrotizing pneumonia and respiratory failure.Extrapulmonary complications,including encephalitis,myocarditis,nephritis,hepatitis,or even multiple organ failure,can also arise.In this editorial,we dis-cuss the clinical implications of the significant findings from the article"Serum inflammatory markers in children with M.pneumoniae pneumonia and their predictive value for mycoplasma severity"published by Wang et al.They reported that measuring lactic dehydrogenase,interleukin-6 levels,and D-dimer effectively predicts refractory M.pneumoniae pneumonia cases.

Relationship between parenting stress and behavioral and emotional problems in preschool children: A mediation effect analysis

BACKGROUND Emotional reactions,such as anxiety,irritability,and aggressive behavior,have attracted clinical attention as behavioral and emotional problems in preschool-age children.AIM To investigate the current status of family rearing,parental stress,and behavioral and emotional problems of preschool children and to analyze the mediating effect of the current status of family rearing on parental stress and behavioral/emo-tional problems.METHODS We use convenience sampling to select 258 preschool children in the physical examination center of our hospital from October 2021 to September 2023.The children and their parents were evaluated using a questionnaire survey.Pearson's correlation was used to analyze the correlation between child behavioral and emotional problems and parental stress and family rearing,and the structural equation model was constructed to test the mediating effect.RESULTS The score for behavioral/emotional problems of 258 preschool children was(27.54±3.63),the score for parental stress was(87.64±11.34),and the score for parental family rearing was(31.54±5.24).There was a positive correlation between the behavioral and emotional problems of the children and the“hostile/mandatory”parenting style;meanwhile,showed a negative correlation with the“support/participation”parenting style(all P<0.05).The intermediary effect value between the family upbringing of parents in parental stress and children's behavior problems was 29.89%.CONCLUSION Parental family upbringing has a mediating effect between parental stress and behavioral and emotional problems of children.Despite paying attention to the behavioral and emotional problems of preschool-age children,clinical medical staff should provide correct and reasonable parenting advice to their parents to promote the mental health of preschool-age children.

Clinical,laboratory,and therapeutic differences between immunoglobulin E-mediated and non-immunoglobulin E-mediated cow’s milk protein allergy in children

BACKGROUND Although breast milk is ideal for newborns,in some cases,it is replaced with cow’s milk,which contains proteins that increase the risk of cow’s milk protein allergy(CMPA).AIM To evaluate CMPA prevalence in Bahrain and compare clinical characteristics of children with immunoglobulin E(IgE)-and non-IgE-mediated CMPA.METHODS This retrospective cohort study examined children with CMPA diagnosed at the pediatric gastroenterology outpatient clinic of the Salmaniya Medical Complex,Bahrain,between 2014 and 2022,and assessed CMPA prevalence.Clinical presentations,laboratory findings,dietary modifications,and outcomes were compared between children with IgE-mediated and non-IgE-mediated CMPA.Categorical variables were compared using Fisher’s exact test or Pearson’sχ2 test,whereas continuous variables were compared using Student’s t-test or the Mann-Whitney U test.RESULTS Of 8332 patients,6022(72.3%)adhered to their appointment.Of them,618(10.3%)were suggested of having CMPA and 595(96.3%)were included;CMPA prevalence was 2%.Most patients were Bahraini(93.8%)and males(55.3%).Non-IgE-mediated type accounted for 77.3%cases and IgE-mediated type,22.7%.IgE-mediated CMPA presented more in boys(P=0.030),and later in life(5.1 months±4.5 months vs 4.2 months±4.2 months,P=0.016,95%CI:0.08-1.73),had more associated diseases(P<0.001);and presented with more cutaneous(P=0.024)and respiratory(P=0.003)manifestations,severe symptoms[rash/dry skin(P=0.031),facial swelling/angioedema(P=0.003),failure to thrive(P=0.013),apparent life-threatening event(P<0.001)],and positive physical findings(P=0.002)than non-IgE-mediated CMPA.Most patients were exclusively fed cow milk formula(50.3%).The amino acid-based formula(AAF)was most prescribed(60.5%)with no difference between the two types(P=0.173).Although breastfeeding was recommended to 49.6%,only 8.2%were exclusively breastfed.IgE-mediated CMPA was associated with a longer follow-up duration than non-IgE-mediated CMPA(17.3 months±14.0 months vs 13.5 months±13.4 months,P=0.005,95%CI:1.1-6.3).CONCLUSION This study revealed a high CMPA prevalence with clinical differences between both types that can influence treatment.AAF was most prescribed,while breastfeeding with dietary modification is rarely applied.

Diet fortification for mild and moderate picky eating in typically developed children:Opinion review of Middle East consensus

BACKGROUND Picky eating is a commonly observed behavior among children globally,negatively impacting their physical and mental growth.Although common characteristics distinguish peaky eaters,including food selectivity,food neophobia,and food avoidance,there is no clear definition to assess this behavior.Due to the unavailability of data regarding picky eating,it wasn’t easy to estimate its prevalence.AIM To develop a regional protocol to help healthcare professionals identify and manage mild and moderate picky eating cases.METHODS A virtual roundtable discussion was held in April 2021 to gather the opinions of seven pediatricians and two pediatric dietitians from eight Middle Eastern countries who had great experience in the management of picky eating.The discussion covered different topics,including clearly defining mild and moderate picky eating,identifying the role of diet fortification in these cases,and the possibility of developing a systematic approach to diet fortification.RESULTS The panel identified picky eating as consuming an inadequate amount and variety of foods by rejecting familiar and unfamiliar food.Most of the time,moderate picky eating cases had micronutrient deficiencies with over-or undernutrition;the mild cases only showed inadequate food consumption and/or poor diet quality.Paying attention to the organic red flags like growth faltering and development delay and behavioral red flags,including food fixation and anticipatory gagging,will help healthcare professionals evaluate the picky eaters and the caregivers to care for their children.Although dietary supplementation and commercial food fortification play an important role in picky eating,they were no benefit in the Middle East.CONCLUSION The panel agreed that food fortification through a food-first approach and oral nutritional supplements would be the best for Middle Eastern children.These recommendations would facilitate identifying and managing picky-eating children in the Middle East.

Cardiovascular involvement in multisystem inflammatory syndrome in children and midterm follow-up from a pediatric tertiary center in India

BACKGROUND In multisystem inflammatory syndrome in children(MIS-C)with coronavirus disease 2019,there was paucity of data from low-income and middle-income countries on cardiovascular involvement and its longitudinal outcomes.We planned to estimate the pattern of cardiovascular involvement among children with MIS-C and its mid-term outcomes.AIM To determine association between cardiovascular abnormalities and clinical and laboratory parameters.To study the time-line for resolution of various abnormalities.METHODS In this prospective study done in a tertiary care hospital,270 were recruited from June 2020 to January 2022.Baseline demographic data and clinical presentation were recorded.Laboratory parameters and echocardiography were done at admission.Follow-up was done at 2 weeks,3 months,6 months and 1 year after diagnosis.Descriptive statistics were used for parametric and non-parametric data.Risk factors were identified by multivariate regression analysis.RESULTS The 211(78.2%)had cardiac involvement and 102 needed intensive care unit(ICU)admission.Cardiovascular abnormalities observed were shock 123(45.6%),coronary dilatation 28(10.4%),coronary aneurysm 77(28.5%),left ventricular(LV)dysfunction 78(29.3%),mitral regurgitation(MR)77(28.5%)and pericardial effusion 98(36.3%).Coronary artery aneurysm/dilatation during follow-up at 2 weeks and 1 year were 25.7%and 0.9%respectively.Multivariate regression analysis revealed breathlessness[odds ratio(OR)=3.91,95%CI:1.25-12.21,P=0.019]and hi-flow nasal cannula(HFNC)support(OR=8.5,95%CI:1.06-68.38,P=0.044)as predictors of cardiovascular involvement.Higher mean age(OR=1.16,95%CI:1.02-1.32,P=0.026),breathlessness(OR=4.99,95%CI:2.05-12.20,P<0.001),gallop(OR=4.45,95%CI:0.41-2.52,P=0.016),MR(OR=3.61,95%CI:1.53-8.53,P=0.004)and invasive ventilation(OR=4.01,95%CI:1.28-12.58,P=0.017)were predictive of LV dysfunction.Altered sensorium(OR=4.96,95%CI:2.23-11.02,P<0.001),headache(OR=6.61,95%CI:1.46-29.92,P=0.014),HFNC(OR=7.03,95%CI:2.04-24.29,P=0.002),non-rebreathing mask usage(OR=21.13,95%CI:9.00-49.61,P<0.001)and invasive ventilation(OR=5.64,95%CI:1.42-22.45,P=0.014)were risk factors for shock.Anemia was a risk factor for coronary involvement(OR=3.09,95%CI:1.79-5.34,P<0.001).CONCLUSION Significant number of children with MIS-C had cardiovascular involvement contributing to higher ICU management.Although shock resolved quickly,resolution of ventricular function and coronary abnormalities were slower,and hence warrants a structured long-term follow-up protocol.

Determination of Melamine by Infrared Spectroscopy Based on Nonlinear Modeling

[Objective] The aim was to develop a nonlinear model of quantitative analysis of melamine content by infrared spectroscopy and provide theoretical basis for the nondestructive detection of melamine. [Method] According to dynamics,mathematical modeling and optimization theory,linear and nonlinear models were respectively set up by taking an absorption peak of 1 550 cm-1 as characteristic absorption peak. [Result] The correlation coefficient of nonlinear model was 0.922 7 and the recovery was 96%,which showed that the nonlinear model was more accurate than linearity model with correlation coefficient of 0.904 9 and recovery of 557%. [Conclusion] It is feasible to determine melamine content by using the nonlinear model quantitatively.

Simultaneous Determination of Melamine, Ammelide, Ammeline, and Cyanuric Acid in Milk and Milk Products by Gas Chromatography-tandem Mass Spectrometry

Objective To develop an analytical method for simultaneously qualitative and quantitative determination of melamine and triazine-related by-products including ammelide, ammeline, and cyanuric acid in milk and milk products by gas chromatography- tandem mass spectrometry （GC-MS/MS）. Methods Melamine and triazine-related by-products namely ammelide, ammeline and cyanuric acid in the samples were extracted in a solvent mixture of diethylamine, water, and acetonitrile （10：40：50, V/V/V）. After centrifugation, an aliquot of the supernatant was evaporated to dryness under a gentle stream of nitrogen gas, and then melamine and triazine-related by-products were derivatized using BSTFA with 1% TMCS. The derivatives of melamine and its analogues were determined by gas chromatography/tandem mass spectrometry using multiple reactional monitoring （MRM） with 2, 6-Diamino-4-chloropyrimidine （DACP） being used as an internal standard. Results The linear detectable ranges were from 0.004 mg/kg to 1.6 mg/kg for melamine, ammelide, ammeline, and cyanuric acid with a correlation coefficient no less than 0.999. The recovery rates of the tour compounds in spiked blank milk powder at concentrations 0.5, 1, 2 mg/kg were between 61.4%-117.2%, and the relative standard deviation was no more than 11.5% （n=6）. The detection limits of melamine, ammelide, ammeline and cyanuric acid in milk powder were 0.002 mg/kg with a ratio of signal to noise of 3. Conclusion This GC-MS/MS method for simultaneous determination of melamine, ammelide, ammeline, and cyanuric acid in milk and milk products is sensitive and specific.

A Survey on Occurrence of Melamine and Its Analogues in Tainted Infant Formula in China

Objective To investigate the occurrence and concentrations of melamine and its analogues in tainted infant formula and to identify the etiologic factors for the urinary stones epidemic in infants and young children in China in 2008. Methods Sanlu infant formula samples were collected from families of the affected children in Gansu province, and markets in Gansu and Hebei provinces and Beijing city. Melamine and its analogues, including cyanuric acid, ammeline, and ammelide were measured by gas chromatography/tandem mass spectrometry. Results High prevalence and concentrations of melamine were found in Sanlu infant formula samples, with low concentrations of cyanuric acid, ammeline and ammelide. Melamine were detected in 87 out of 111 Sanlu infant formula samples with a range of 118 to 4 700 mg/kg, Conclusion The results provide strong evidence for melamine as the etiological factor for the urinary stones epidemic in infants and young children in China in 2008.

Flame retardant polyamide 6 by in situ polymerization of ε-caprolactam in the presence of melamine derivatives

An improved method for preparing melamine cyanurate （MCA） based flame retardant polyamide 6 （FRPA6） materials has been proposed. This processing method, i.e., improved in situ polymerization, was used to synthesize flame retardant PA6. In situ formed MCA nanoparticles were supposed to be linked to PA6 chains in the ε-caprolactam hydrolytic polymerization system to obtain startype polymers for the first time. Through TEM photographs, it can be found that the in situ formed MCA nanoparticles with diametric size of less than 50 nm, are nanoscaled, highly uniformly dispersed in the PA6 matrix. Synthesized flame retardant PA6 have good fire performance which can achieve UL-94 V-0 rating at 1.6 mm thickness with the presence of 7.34 wt.% MCA in the matrix.

Study on Migration of Melamine from Food Packaging Materials on Markets

Objectives To study the migration of melamine into foods from plastic food packaging materials and dairy product containers commonly used in China. Methods 37 samples were collected from the market. The EU migration testing conditions were adopted with distilled water, 3% acetic acid, n-hexane and 15% ethanol being chosen as the simulating solutions. The HPLC method was used to detect melamine. Results No melamine was detected in 15 dairy product containers. Among the 22 plastic samples, 16 of polypropylene, and polycarbonate types had no detectable amount melamine while a low level of melamine was found in 3 of the 6 melamine resin containers. Conclusion Migration of melamine from food packaging materials in China market is in line with the requirements of EU.

Melamine modified carbon felts anode with enhanced electrogenesis capacity toward microbial fuel cells

Surface electropositivity and low internal resistance are important factors to improve the anode performance in microbial fuel cells (MFCs). Nitrogen doping is an effective way for the modification of traditional carbon materials. In this work, heat treatment and melamine were used to modify carbon felts to enhance electrogenesis capacity of MFCs. The modified carbon felts were characterized using X-ray photoelectron spectroscopy (XPS), scanning electron microscope (SEM), atomic force microscopy (AFM) and malvern zeta potentiometer. Results show that the maximum power densities under heat treatment increase from 276.1 to 423.4 mW/m(2) (700 degrees C) and 461.5 mW/m(2) (1200 degrees C) and further increase to 472.5 mW/m(2) (700 degrees C) and 515.4 mW/m(2) (1200 degrees C) with the co-carbonization modification of melamine. The heat treatment reduces the material resistivity, improves the zeta potential which is beneficial to microbial adsorption and electron transfer. The addition of melamine leads to the higher content of surface pyridinic and quaternary nitrogen and higher zeta potential. It is related to higher MFCs performance. Generally, the melamine modification at high temperature increases the feasibility of carbon felt as MFCs's anode materials. (C) 2016 Science Press and Dalian Institute of Chemical Physics, Chinese Academy of Sciences. Published by Elsevier B.V. and Science Press. All rights reserved.

Preparation and characterization of hexadecane microcapsule with polyurea-melamine formaldehyde resin shell materials

This paper gives a brief report of the preparation of hexadecane microcapsule with polyurea-melamine formaldehyde resin shell materials(HMPM).The sealing performance and thermal stability of HMPM was enhanced much more effectively than that of microcapsule with polyurea shell material(HPM).The results of microscopical imaging analysis system,DSC,TG,and laser particle analyzer were briefly introduced.