Abundance and sources of particulate polycyclic aromatic hydrocarbons and aromatic acids at an urban site in central China

We conducted a simultaneous field study of PM_(2.5)-bound particulate polycyclic aromatic hydrocarbons(PAHs)and aromatic acids(AAs)in a polluted city Zhengzhou to explore the concentration,sources and potential conversion pathways between PAHs and AAs in different seasons.The average concentrations of PM_(2.5),28PAHs and 8AAs during the sampling period were 77μg/m^(3),75 ng/m^(3),and 283 ng/m^(3),respectively.The concentration of both28PAHs and 8AAs were highest in winter and lowest in summer with ratios of 6.3 and 2.3,respectively.PAHs with 5-7 rings were the main components of PAHs(52%),followed by 4rings PAHs(30%)and 2-3 rings PAHs(18%).According to the source appointment results obtained by positive matrix factorization,the main sources of PAHs were combustion and vehicle emissions,which account for 37%and 34%,respectively.8AAs were divided into three groups,including four benzene dicarboxylic acids(B2CAs),three benzene tricarboxylic acids(B3CAs)and one benzene tetracarboxylic acid(B4CA).And interspecies correlation analysis with PM_(2.5)source markers were used to investigate potential sources.Phthalic acid(o-Ph)was the most abundant specie of 8AAs(157 ng/m^(3),55%of 8AAs),which was well correlated with sulfate.Meanwhile,B3CAs and B4CA were highly correlated with sulfate and weakly correlated with levoglucosan,suggesting that secondary formation was their main source.As logical oxidation products of PAHs,o-Ph and B3CAs showed good correlations with a number of PAHs,indicating possible photochemical oxidation pathway by PAHs.In addition,O_(3),NO_(2),temperature and relative humidity have positive effects on the secondary formation of B3CAs.

Molecular origin for pH-responsive wormlike micelles of zwitterionic surfactants triggered by aromatic acid derivatives

Introduction of aromatic acid derivatives(AADs)into zwitterionic surfactants is an efficient method to prepare wormlike micelles with pH-controllable viscosity;however,the coincident molecular origin of AAD/zwitterionic surfactant binary mixtures remains unclear.Herein,the self-assembly of hydroxyl derivatives of benzoic acid(BA)and cetyldimethyl betaine(BS-16)mixtures in water was systematically assessed,and various factors,such as the molecular structure,molar ratio of AAD and BS-16,and solution pH,were investigated.The structure-property relationship of AAD/BS-16 binary mixtures was established,which provided the molecular origin for the effect of AAD on micellar microstructures and the pH-induced morphological transitions.The ortho-substituted hydroxyl moiety in the BA molecule facilitated the formation of larger wormlike micelles,whereas the effect of the meta-substituted moiety was less significant.The para-substituted hydroxyl moiety in BA did not favor micellar growth.This moiety exhibited similar characteristics to the increasing hydroxyl moiety number in the AAD molecules or solution pH where the negative effects of steric hindrance and electrostatic interactions of molecules in micelles aredominant.

Heterogeneously elevated branched-chain/aromatic amino acids among new-onset type-2 diabetes mellitus patients are potentially skewed diabetes predictors

BACKGROUND The lack of specific predictors for type-2 diabetes mellitus(T2DM)severely impacts early intervention/prevention efforts.Elevated branched-chain amino acids(BCAAs:Isoleucine,leucine,valine)and aromatic amino acids(AAAs:Tyrosine,tryptophan,phenylalanine)show high sensitivity and specificity in predicting diabetes in animals and predict T2DM 10-19 years before T2DM onset in clinical studies.However,improvement is needed to support its clinical utility.AIM To evaluate the effects of body mass index(BMI)and sex on BCAAs/AAAs in new-onset T2DM individuals with varying body weight.METHODS Ninety-seven new-onset T2DM patients(<12 mo)differing in BMI[normal weight(NW),n=33,BMI=22.23±1.60;overweight,n=42,BMI=25.9±1.07;obesity(OB),n=22,BMI=31.23±2.31]from the First People’s Hospital of Yunnan Province,Kunming,China,were studied.One-way and 2-way ANOVAs were conducted to determine the effects of BMI and sex on BCAAs/AAAs.RESULTS Fasting serum AAAs,BCAAs,glutamate,and alanine were greater and high-density lipoprotein(HDL)was lower(P<0.05,each)in OB-T2DM patients than in NW-T2DM patients,especially in male OB-T2DM patients.Arginine,histidine,leucine,methionine,and lysine were greater in male patients than in female patients.Moreover,histidine,alanine,glutamate,lysine,valine,methionine,leucine,isoleucine,tyrosine,phenylalanine,and tryptophan were significantly correlated with abdominal adiposity,body weight and BMI,whereas isoleucine,leucine and phenylalanine were negatively correlated with HDL.CONCLUSION Heterogeneously elevated amino acids,especially BCAAs/AAAs,across new-onset T2DM patients in differing BMI categories revealed a potentially skewed prediction of T2DM development.The higher BCAA/AAA levels in obese T2DM patients would support T2DM prediction in obese individuals,whereas the lower levels of BCAAs/AAAs in NW-T2DM individuals may underestimate T2DM risk in NW individuals.This potentially skewed T2DM prediction should be considered when BCAAs/AAAs are to be used as the T2DM predictor.

Simple and Sensitive Determination of Aromatic Acids in Coconut Water by g-C3N4@SiO2 Based Solid-phase Extraction and HPLC-UV Analysis

In this study, graphitic carbon nitride deposited silica（g-C3N4@SiO2） was prepared by simple pyrolysis of melamine on silica and then used as a solid-phase extraction（SPE） sorbent for the extraction of four representative aromatic acids including benzoic acid（BA）, salicylic acid（SA）, indolyl-3-butyricacid（IBA） and naphthalene acetic acid（NAA） in coconut water（CW） samples, g-C3N4@SiO2 exhibited an excellent adsorption capacity for the four aromatic acids, which are in the concentration range of 500--558.8 gg/g. The four aromatic acids could be directly captured by g-C3N4@SiO2 from CW samples within 5 rain. Thus, a rapid, simple and effective method for the analy- sis of four aromatic acids in CW samples was developed by coupling g-C3N4@SiO2-based SPE with high performance liquid chromatography-ultraviolet（HPLC-UV） detection. The linearity of the developed method was in the range of 20--1000 ng/mL and its limit of detection was in the range of 1.9--5.7 ng/mL, which were signi- ficantly lower than those of the reported similar methods. The intra-day and inter-day precisions（based on the relative standard deviation, n=3） of the four aromatic acids were under 9.5% and 10.4%, respectively. The developed method was applied to determining the four aromatic acids in real CW samples and the spiked recoveries varied from 81.1% to 121.8%.

Extending aromatic acids on TiO_(2)for cooperative photocatalysis with triethylamine:Violet light-induced selective aerobic oxidation of sulfides

Designing visible light photocatalysts with a metal oxide semiconductor as the starting material could expand a new horizon for the conversion and storage of solar energy.Here,the benchmark photocatalyst TiO_(2) was used to pursue this goal by anchoring aromatic acids.Extending the aromatic acid was strategically deployed to design TiO_(2) complexes with violet light-induced selective aerobic oxidation of sulfide as the probe reaction.With benzoic acid(BA)as the initial molecule,horizontally extending one or two benzene rings furnishes 2-naphthoic acid(2-NA)and 2-anthracene acid(2-AA).Moreover,triethylamine(TEA),an electron transfer mediator,was introduced to maintain the integrity of the anchored aromatic acids.Notably,there was a direct correlation between theπ-conjugation of aromatic acid ligand and the selective aerobic oxidation of sulfides.Among the three aromatic acids,2-AA delivered the best result over TiO_(2) due to the most extensiveπ-conjugated system.Ultimately,violet light-induced selective aerobic oxidation of sulfides into corresponding sulfoxides was conveniently realized by cooperative photocatalysis of 2-AA-TiO_(2) with 10 mol%of TEA.This work affords an extending strategy for designing the next-generation ligands for semiconductors to expand visible light-induced selective reactions.

Synthesis and Properties of Ternary Europium Complexes with Aromatic Carboxylic Acid and Nitrogen-Containing Heterocyclic Ligand

Seven ternary Eu （m） complexes were synthesized with aromatic carboxylic acid （benzoic acid, phenylacetic acid, phenylpropionic acid and cinnamic acid） as the first ligand and 1,10-phenanthro- line or 2,2＇-dipyridyl as the second ligand. The ternary Eu（ Ⅲ ） complexes were characterized by elemental analysis, IR and TG-DTG methods. In these complexes, the Eu （Ⅲ） ions are bonded to the oxygen atoms of carboxylate and the nitrogen atoms of neutral ligands. Four complexes whose second ligand is 1,10- phenanthrolin have fine thermal stability. Excitation and luminescence spectra of the tide complexes reveal that the fluorescence of the complexes in which 1,10- phenanthrolin as the second ligand are more intensive than those complexes in which 2, 2＇-dipyridyl as the second ligand. The order of the strongest emission peak of seven ternary complexes is： Eu（β-PPA）3phen 〉 Eu（BA）3phen 〉 Eu（PLA）3phen 〉 Eu（BA）3bipy 〉 Eu （ PEA）3bipy 〉 Eu （ CA ）3phen · H2O 〉 Eu （ CA ）3bipy （BA ： benzoic ; PEA ： phenylacetic ; β-PPA ：

THERMODYNAMIC STUDY ON ADSORPTION OF AROMATIC SULFONIC ACIDS ONTO MACROPOROUS WEAK BASE ANION EXCHANGER FROM AQUEOUS SOLUTIONS

The adsorption equilibrium isotherms of three aromatic sulfonic acid compounds, 2-naphthalenesulfonic acid, p-toluenesulfonic acid and p-chlorobenzenesulfonic acid, from aqueous solutions by macroporous weak base anion exchanger within the temperature range of 293 K-313 K were obtained. Several isotherm equations were correlated with the equilibrium data, and the experimental data was found to fit the three-parameter Redlich-Peterson equation best within the entire range of concentrations. The study showed that the hydrophobicity of solute has distinct influence on adsorption capacity of the anion exchanger for the aromatic sulfonic acid. Moreover, estimations of the isosteric enthalpy, free energy, and entropy change of adsorption were also reported. The positive isosteric enthalpy and entropy change for adsorption indicate an endothermic and entropy driven process in the present study.

Separation of Aromatic Carboxylic Acids in IC and the Study on the Relationship Between Retention Behavior and Electrostatic Potential

A method has been developed for separation of 20 kinds of aromatic carboxylic acid using anion-exchange chromatography. A Dionex IonPac AS9-HC guard column （250mm×2mm） was used with a 9mmol/L sodium carbonate solution containing 50% （v/v） acetonitrile as eluent. A set of retention time data has been obtained using a conductivity detector DS6. Furthermore, geometrical optimization and electrostatic potential calculation of 20 kinds of aromatic carboxylic acid have been performed at the HF/6-31G＊ level of theory. A number of statistically-based parameters derived from molecular surface electrostatic potential have been obtained. Linear relationship between retention time and structural parameters has been established by multiple regression method. The result shows that parameters derived from electrostatic potential Vs ＋, Vs -, П together with the dipole moment μ can be well used to express the quantitative structure-retention time of this kind of aromatic carboxylic acid. Good predictive capability has also been demonstrated. The result has provided a framework which further proves the general applicability of this electrostatic potential parameter set to a great extent,and with which the ion chromatographic adsorption mechanism can be investigated.

Aromatic L-amino acid decarboxylase cells in the spinal cord:a potential origin of monoamines

Monoamine neurotransmitters include catecholamines and indoleamines. The most common catecholamines are do- pamine （DA）, noradrenaline （NA） and adrenaline, which are produced from phenylalanine and tyrosine; whereas the most common indoleamine is serotonin （5-hydroxytrypta mine, 5-HT）, which is produced from 5-hydroxytryptophan （5-HTP）.

Recent progress in the applications of presynaptic dopaminergic positron emission tomography imaging in parkinsonism

Nowadays,presynaptic dopaminergic positron emission tomography,which assesses deficiencies in dopamine synthesis,storage,and transport,is widely utilized for early diagnosis and differential diagnosis of parkinsonism.This review provides a comprehensive summary of the latest developments in the application of presynaptic dopaminergic positron emission tomography imaging in disorders that manifest parkinsonism.We conducted a thorough literature search using reputable databases such as PubMed and Web of Science.Selection criteria involved identifying peer-reviewed articles published within the last 5 years,with emphasis on their relevance to clinical applications.The findings from these studies highlight that presynaptic dopaminergic positron emission tomography has demonstrated potential not only in diagnosing and differentiating various Parkinsonian conditions but also in assessing disease severity and predicting prognosis.Moreover,when employed in conjunction with other imaging modalities and advanced analytical methods,presynaptic dopaminergic positron emission tomography has been validated as a reliable in vivo biomarker.This validation extends to screening and exploring potential neuropathological mechanisms associated with dopaminergic depletion.In summary,the insights gained from interpreting these studies are crucial for enhancing the effectiveness of preclinical investigations and clinical trials,ultimately advancing toward the goals of neuroregeneration in parkinsonian disorders.

Highly efficient Rod-shape Poly(methacrylic acid-co-styrene-codivinylbenzene)High-performance Liquid Chromatographic Column

A highly efficient copolymer (methacrylic acid - co - styrene - divinylbenzene) in situ making high-performance liquid chromatographic column was prepared and evaluated. The column efficiency calculated in terms of height equivalent to a theoretical plate was 25 mu m and rapid separations of small molecules such as substituted aromatic hydrocarbons and aromatic acids were achieved within five minutes.

Serial therapies oriented by surgery for large primary liver carcinoma

Objective: To discuss the methods and effects of serial therapies oriented by surgery in the treatment of pri- mary large liver cancers. Methods: From January 1993 to June 1999, 191 pa- tients with large liver carcinoma were treated surgi- cally. The size of tumors varied from 5.2 to 19.7 cm (mean 9.4 cm). Several types of liver resections were made in 121 patients and as a supplement, cry- osurgery was carried out for the remaining 70 pa- tients. Importable drug delivery system was institu- ted intraoperatively. Transcatheter arterial chemo- embolization (THP 30-60 mg, E-ADM 20-40 mg, CDDP 40-80 mg, MMC 10-20 mg, iodin oil 5-30 ml), percutaneous ethanol injection, bioimmunother- apy and traditional Chinese medicine were used pre- and post-operatively. CT angiography and CT dur- ing arterial portography were used to find satellite nodules. Early stage recurrences were predicted by AFPmRNA in peripheral blood. Child-Pugh's classi- fication plus branch chain amino acid/aromatic ami- no acid ratio (BCAA/AAA) was adopted in evalua- ting pre-operative liver functions. Results: Marked results were observed after serial treatments oriented by surgery. The 1-, 3- and 5- year survival rates in resection group were 75.8 %, 45.6% and 30.4%. respectively. The 1- and 3-year survival rates in cryosurgery group were 63.2 % and 37.0 %. The operative mortality was 1.57 %. Recur- rence rates were 69.2 % in AFPmRNA positive group and 33.3% in AFPmRNA negative group (P< 0.05). The BCAA/AAA ratio was lower than 1.5 in two patients who died of hepatic failure after resec- tion. Conclusions: Serial treatments with surgery as the chief modality gives satisfactory results in patients with large primary liver carcinoma. This regimen should be regarded as a main strategy to deal with large liver carcinoma. AFPmRNA in the peripheral blood, signifying a recurrence, may become a new clinical parameter. The BCAA/AAA ratio plus Child-Pugh's classification is able to evaluate more accurately liver function reserve before surgery.

Impaired gluconeogenesis in a porcine model of paracetamol induced acute liver failure

AIM:To investigate glucose homeostasis and in particular gluconeogenesis in a large animal model of acute liver failure(ALF).METHODS:Six pigs with paracetamol induced ALF under general anaesthesia were studied over 25 h.Plasma samples were withdrawn every five hours from a central vein.Three animals were used as controls and were maintained under anaesthesia only.Using 1 H NMR spectroscopy we identified most gluconeogenic amino acids along with lactate and pyruvate in the animal plasma samples.RESULTS:No significant changes were observed in the concentrations of the amino acids studied in the animals maintained under anaesthesia only.If we look at the ALF animals,we observed a statistically significant rise of lactate(P<0.003)and pyruvate(P<0.018) at the end of the experiments.We also observed statistically significant rises in the concentrations of alanine(P<0.002),glycine(P<0.005),threonine(P< 0.048),tyrosine(P<0.000),phenylalanine(P<0.000) and isoleucine(P<0.01).Valine levels decreased significantly(P<0.05).CONCLUSION:Our pig model of ALF is characterized by an altered gluconeogenetic capacity,an impaired tricarboxylic acid(TCA)cycle and a glycolytic state.

Research Progress of Metal-Organic Frameworks Based on Aromatic Polycarboxylic Acid

Metal-organic frameworks （MOFs） have attracted tremendous attention due to their fascinating structure types and extensive application prospect in many fields. In the process of synthesis, aromatic polycarboxylic acid as ligand plays an important role in constructing functional MOFs. In this review, we have summarized the research progress on the synthesis and structures analysis of MOFs based on aromatic polycarboxylic acids as well as their potential applications in magnetism, gas adsorption, separation, photodegradation, catalysis and emission.

Aromatic inorganic acid radical

Stable radicals are challenging to prepare due to their intrinsic high reactivity.Herein,three trisphenolamine radicals were readily synthesized and exhibited unexpected thermal/electrochemical stability and semiconductor property.These three nitroxide radicals could be considered as a class of aromatized nitro groups or HNO3 derivatives.The closed-shell nitro-like and open-shell nitroxide resonance structure contribute to their outstanding stability.Furthermore,the tunable ground states,extremely low band gap and p-type charge transport properties were systematically investigated.More importantly,the work presents the concept of aromatic inorganic acid radical(AIAR)and aggregation-induced radical(AIR)mechanism to understand the intrinsic structureproperty relationship of these radicals.In addition,we provide a novel strategy for the design of stable and low bandgap radicals for organic electronics,magnetics,spintronics,etc.

A novel strategy for high-specificity, high-sensitivity, and high-throughput study for gut microbiome metabolism of aromatic carboxylic acids

Aromatic carboxylic acids(ACAs) may be as transformed key metabolites via gut microbiome for playing better pharmacological effects. However, it's rare to achieve high-specificity, high-sensitivity, and highthroughput detection simultaneously, especially, for tracing trace ACAs in gut microbiome. In this work,firstly, a novel dual-template and double-shelled molecularly imprinted 96-well microplates(DDMIPs)was designed and amplified signal for p-hydroxybenzoic acid(PBA) and 3,4,5-trimethoxycinnamic acid(TMA). Additionally, the DDMIPs and a stable isotope labeling derivatization(SILD) method combined with the ultra-high performance liquid chromatography triple quadrupole tandem mass spectrometry(UHPLC-TQ MS) was firstly stepwise integrated, achieving high-effective, high-sensitive, and highthroughput study of gut microbiome metabolism. The whole strategy showed lower limits of detections(LODs) up to 1000 folds than the traditional method, and revealed a more real metabolism-time profile of PBA and TMA by 3-step signal amplification. The platform also laid the foundation for fast, simple,high-selective, high-effective, and high-throughput metabolism and pharmacological research.

Influence of Different Organic Carboxylate Anions on the Crystal Structure of Silver(Ⅰ)Coordination Polymers

The reaction of AgNO3 , 4,4′-bipyridine （bpy） and 2,2′-bipyridine-3,3′-dicarboxylic acid （H2bpdc）/2,2′-biquinoline-4,4′-dicarboxylic acid （H2bqdc）/1,3-benzenedicarboxylic acid （H2bdc） gave rise to block-like crystals of [Ag4（bpy）2（bpdc）2]·13H2O（1）, [Ag2（bpy）（bqdc）（H2O）]·4.5H2O（2） and [Ag2（bpy）2（H2O）2]（bdc）·3H2O（3） by slow evaporation. All the three complexes contain sandwich-like crystal structures, in which anionic sheets built up from different anions （bpdc2- , bqdc2- and bdc2- ） and lattice water molecules via rich hydrogen-bonding interactions are inserted between the cationic silver complex layers, and the abundant Ag···Ag, Ag···N and π-π stacking interactions further strengthen the 3D frameworks. The lattice water molecules are situated among the framework of crystal structure and stabilized by rich hydrogen-bonding interactions, and lattice water molecules may play a role in the orientation of organic anions in the crystal packing. Additionally, the thermal properties of 1, 2 and 3 were also discussed in detail.

One-pot synthesis of N-aryl propargylamine from aromatic boronic acid,aqueous ammonia,and propargyl bromide under microwave-assisted conditions

A facile,one-pot synthesis of N-aryl propargylamine from aromatic boronic acid,aqueous ammonia,and propargyl bromide has been achieved under microwave-assisted conditions.The reactions can be smoothly completed within a total 10 min through a two-step procedure,including copper-catalyzed coupling of aromatic boronic acids with aqueous ammonia and following propargylation by propargyl bromide.

Catalyst-free Photochemical Bromination of Unprotected Aromatic Amino Acid Derivatives by Using a Rotating Ultraviolet Photoreactor

Aromatic amino acid halides are valuable amino acid derivatives and fundamental building blocks that are used to various coupling reaction^1-3!,such as Heck,Suzuki and Ullmann reaction[4-7],and also important precursors of active natural products,pharmaceuticals and chiral auxiliaries[8-9].

THE MASS SPECTRA OF AROMATIC CONJUGATED POLYENIC ACID,METHYL BENZOATE,METHYL PHENYL KETONE,BENZONITRILE AND ANILINE AND THEIR QUANTUM CHEMICAL CALCULATIONS

A quantitative interpretation of mass spectra of complex organic compounds so far is notvery perfect and needs some further investigation. In this paper a mechanism of cleft-rate-determining-steps of aromatic conjugated polyenic acid, methyl benzoate, methyl phenyl ketone,benzonitrile and aniline is proposed, and various quantum parameters of molecular ions ofaromatic conjugated polyenic compounds, together with their framents are calculated bymeans of CNDO/2 method. Through the process of calculation, the peak-height of mass spectracan be quantitatively interpreted, which means that the main factors which influence the cleftforms of simple cleavage of mass spectra of conjugated compounds given by the authorsmight be true to some extent.