Barbier Polymerization-Induced Emission towards Fully Substituted Polyethylene Analogues with Non-Traditional Intrinsic Luminescence.

The properties of polyethylene are highly dependent on the variety and quantity of substitutions. Generally, polyethylene can only be fully substituted with fluorine atoms, mainly e. g., polytetrafluoroethylene and nafion, because atomic radius of fluorine atom is small enough. The preparation of fully substituted polyethylene analogues (FSPEA) and their non-traditional intrinsic luminescence (NTIL) are attractive, especially for substitutions with relatively larger atomic radii than a fluorine atom. Here, Barbier polymerization-induced emission (PIE) is demonstrated as a universal method for the molecular design of NTIL type FSPEAs with intriguing aggregation-induced emission (AIE) behaviors. Through Barbier polymerization of diphenyldichloromethane and different peroxyesters in the presence of Mg in one pot, a series of FSPEAs, including polytriphenylethanol (PTPE), polydiphenylfurylethanol (PDPFE), polydiphenylthiophenylethanol (PDPTE) and polydiphenylnaphthylethanol (PDPNE) have been successfully prepared. Further potential applications for explosive detection, artificial light-harvesting system and white phosphor-converted light-emitting diode are investigated. Therefore, this work opens up a new approach for the molecular design of FSPEA with non-conjugated luminescence, which may cause inspirations to different research fields like polyolefin and luminescent materials.

The Joint Impact of Trait Competitiveness and Competitive Climate on Depressive Symptoms and Anxiety Among Adolescents.

Competitive climate and individual competitive characteristics jointly affect the mental health of adolescents. Based on person-environment fit theory, this study aimed to examine the effects of the match between trait competitiveness and competitive climate on depressive symptoms and anxiety. In this study, data were collected from 2235 Chinese adolescents in the 10th to 12th grades (48.8% girls; Mage = 16.06 years, SDage = 0.95). Self-reported depressive symptoms, general anxiety, trait competitiveness, and competitive climate were assessed. Polynomial regression analyses and response surface analyses indicated that in cases of congruence, as trait competitiveness and competitive climate increase, depressive symptoms and anxiety increase, as do their growth rate. In cases of incongruence, higher levels of depressive symptoms and anxiety are found when trait competitivenesså competitive climate compared to when competitive climateå trait competitiveness. And as trait competitiveness become increasingly higher than competitive climate, the level of depressive symptoms and anxiety were higher. This serves as a reminder for families and schools to place special emphasis on the mental health of adolescents with high levels of trait competitiveness who may exhibit high levels of depressive symptoms and anxiety.

Rapid screening and evaluation of natural antioxidants from leaf, stem, and root of Artemisia argyi by online liquid microextraction combined with HPLC-based antioxidant assay system coupled with calibration quantitative analysis.

To reveal the utilization value of leaf, stem, and root of Artemisia argyi, a rapid online liquid microextraction combined with a high-performance liquid chromatography coupled with 2,2-nitrogen-di (3-ethyl-benzothiazole-6-sulfonic acid) diammonium salt antioxidant assay system was established for analysis of antioxidants in the leaf, stem, and root of A. argyi, and a calibration quantitative method of antioxidant activity with equivalent chlorogenic acid was proposed. Thirty-three positive peaks were identified; among them, 12 compounds were found that possess good antioxidant activity including eleven organic acids (components 2-4, 8, 11-14, 17, 19, and 21) and one flavonoids (component 22). The proposed calibration quantitative method avoided the influence of content of compound and compared the extent of radical scavenging capacity of five antioxidant compounds, which were ranked as follow: 3,5-dicaffeoylquinic acid > 3,4-dicaffeoylquinic acid ≈ 4,5-dicaffeoylquinic acid > 1,4-dicaffeoylquinic acid > chlorogenic acid. In conclusion, this study provided composition and biological potential for the future development of the leaf, stem, and root of A. argyi. It is believed that the online liquid microextraction combined with high-performance liquid chromatography based antioxidant assay system can be widely used for the rapid screening of natural antioxidant components in the different parts of natural products.

Antibody responses to SARS-CoV-2 Omicron infection in patients with hematological malignancies: A multicenter, prospective cohort study.

Little is known about antibody responses to natural Omicron infection and the risk factors for poor responders in patients with hematological malignancies (HM). We conducted a multicenter, prospective cohort study during the latest Omicron wave in Chongqing, China, aiming to compare the antibody responses, as assessed by IgG levels of anti-receptor binding domain of spike protein (anti-S-RBD), to Omicron infection in the HM cohort (HMC) with healthy control cohort (HCC), and solid cancer cohort (SCC). In addition, we intend to explore the risk factors for poor responders in the HMC. Among the 466 HM patients in this cohort, the seroconversion rate was 92.7%, no statistically difference compared with HCC (98.2%, p = 0.0513) or SCC (100%, p = 0.1363). The median anti-S-RBD IgG titer was 29.9 ng/mL, significantly lower than that of HCC (46.9 ng/mL, p < 0.0001) or SCC (46.2 ng/mL, p < 0.0001). Risk factors associated with nonseroconversion included no COVID-19 vaccination history (odds ratio [OR] = 4.58, 95% confidence interval [CI]: 1.75-12.00, p = 0.002), clinical course of COVID-19 ≤ 7 days (OR = 2.86, 95% CI: 1.31-6.25, p = 0.008) and severe B-cell reduction (0-10/µL) (OR = 3.22, 95% CI: 1.32-7.88, p = 0.010). Risk factors associated with low anti-S-RBD IgG titer were clinical course of COVID-19 ≤ 7 days (OR = 2.58, 95% CI: 1.59-4.18, p < 0.001) and severe B-cell reduction (0-10/µL) (OR = 2.87, 95% CI: 1.57-5.24, p < 0.001). This study reveals a poor antibody responses to Omicron (BA.5.2.48) infection in HM patients and identified risk factors for poor responders. Highlights that HM patients, especially those with these risk factors, may be susceptible to SARS-CoV-2 reinfection, and the postinfection vaccination strategies for these patients should be tailored. Clinical trial: ChiCTR2300071830.

Quantitative association of cerebral blood flow, relaxation times and proton density in young and middle-aged primary insomnia patients: A prospective study using three-dimensional arterial spin labeling and synthetic magnetic resonance imaging.

Objectives: To quantitatively measure the T1 value, T2 value, proton density (PD) value, and cerebral blood flow (CBF) in young and middle-aged primary insomnia (PI) patients, and analyze the correlations between relaxation times, PD, and CBF to explore potential brain changes. Methods: Cranial magnetic resonance (MR) images of 44 PI patients and 30 healthy subjects were prospectively collected for analysis. The T1, T2, PD, and CBF values of the frontal lobe, parietal lobe, temporal lobe, and occipital lobe were independently measured using three-dimensional arterial spin labeling (3D-ASL), synthetic magnetic resonance imaging (syMRI) and a whole-brain automatic segmentation method. The differences of these imaging indices were compared between PI patients and healthy subjects. Follow-up MR images were obtained from PI patients after 6 months to compare with pre-treatment images. The Wilcoxon signed rank test and Spearman rank were used for statistical analysis. Results: Bilateral CBF asymmetry was observed in 38 patients, with significant differences in both the T2 value and CBF between the four lobes of the brain (p < 0.01). However, no significant difference was found in the T1 and PD values between the bilateral lobes. A negative correlation was found between CBF and T2 values in the right four lobes of patients with primary insomnia (PI). During follow-up examinations, five PI patients showed a disappearance of insomnia symptoms and a decrease in CBF in both brain lobes. Conclusion: Insomnia symptoms may be associated with high CBF, and most PI patients have higher CBF and lower T2 values in the right cerebral hemispheres. The right hemisphere appears to play a critical role in the pathophysiology of PI. The 3D-ASL and syMRI technologies can provide a quantitative imaging basis for investigating the brain conditions and changes in young and middle-aged PI patients.

Identification and quantification of nine compounds in Fangwen Jiuwei decoction by liquid chromatography-mass spectrometry.

Fangwen Jiuwei Decoction is a traditional Chinese medicine preparation for the treatment of pneumonia developed by Shenzhen Bao'an Chinese Medicine Hospital, which shows remarkable clinical responses. Qualitative and quantitative analyses of the main active compounds are crucial for the quality control of traditional Chinese medicine prescription in clinical application. In this study, we identified nine active compounds essential for the pharmacological effects of Fangwen Jiuwei Decoction based on the analysis of the Network Pharmacology and relevant literature. Moreover, these compounds can interact with several crucial drug targets in pneumonia based on molecular docking. We applied high-performance liquid chromatography-tandem mass spectrometry method was established these nine active ingredients' qualitative and quantitative detections. The possible cleavage pathways of nine active components were determined based on secondary ions mass spectrometry. The results of high-performance liquid chromatography-tandem mass spectrometry were further validated, which show a satisfactory correlation coefficient (r > 0.99), recovery rate (≥93.31%), repeatability rate (≤5.62%), stability (≤7.95%), intra-day precision (≤6.68%), and inter-day precision (≤9.78%). The limit of detection was as low as 0.01 ng/ml. In this study, we established a high-performance liquid chromatography-tandem mass spectrometry method to qualitatively and quantitatively analyze the chemical components in the Fangwen Jiuwei Decoction extract.

HIV-associated Burkitt lymphoma in the combination antiretroviral therapy era: Real-world outcomes and prognostication.

We performed a retrospective study to analyze the clinical characteristics and outcomes of human immunodeficiency virus-associated Burkitt's lymphoma in Chongqing University Cancer Hospital, southwest China, from March 2012 to February 2022. In the entire cohort, the median age was 36 years (range, 28-60 years), and more patients were male (82.4%). The median CD4+ T cell count was 214/µl (range, 54-601), of whom 47.1% had a CD4+ T cell count below 200/µl. Most patients had elevated lactate dehydrogenase (LDH), elevated ß2-MG, extranodal involvement and advanced Ann Arbor stage at diagnosis. With a median follow-up of 11.5 months (range, 1.6-94.9 months), the overall 1-year progression-free survival and overall survival (OS) rates were 27.6% and 47.6%, respectively. The 1-year OS times in the LDH < 3 upper limit of normal and LDH ≥ 3 upper limit of normal groups were 62.5% and 31.3%, respectively (p = 0.008). The 1-year OS times in the received <4 cycles and ≥4 cycles groups were 0% and 77.8%, respectively (p < 0.001). These results demonstrated that LDH < 3 upper limit of normal and received ≥4 cycles of chemotherapy were significantly associated with improved outcomes. However, rituximab administration was not significantly associated with improved outcomes.

One-Pot Synthesis of Stimuli-Responsive Fluorescent Polymers through Polymerization-Induced Emission.

Stimuli-responsive opposite emission (A)/absorption (B) polymer material (A∪B = Ω and A∩B = Ø) represents a novel polymer material that is difficult to prepare. Here, we demonstrate a one-pot strategy for the molecular design of stimuli-responsive opposite emission/absorption polymer material with intriguing properties of opposite emission/absorption and aggregation-induced emission (AIE) type nontraditional intrinsic luminescence (NTIL) in the visible region, through reversible addition-fragmentation chain transfer polymerization-induced emission (PIE) of the N,N-dimethyl-triphenylmethanol moiety. Investigations reveal that NTIL is due to the through-space conjugation effect caused by polymer chain entanglement, when increasing the repeating unit number. The corresponding stimuli-responsive opposite emission/absorption properties are derived from the carbocation-quinoid mechanism, which enables the fluorescence encryption capability. This work therefore demonstrates the proof of concept of a novel opposite emission/absorption polymer material that might cause inspiration in different fields.

The Relationship of Technoference in Conjugal Interactions and Child Smartphone Dependence: The Chain Mediation between Marital Conflict and Coparenting.

With the increasing use of smartphones in our lives, technoference has become a new threat to family relationships and child development. The present study explored the impact of technoference in conjugal interactions on child smartphone dependence and its underlying mechanism. The participants were 6923 fourth grade children (55.0% boys; the average age was 10.60 years) in 545 primary schools and their parents (35.3% fathers). We found that technoference in conjugal interactions was significantly associated with child smartphone dependence. Technoference in conjugal interactions indirectly affected child smartphone dependence through marital conflict or coparenting and a chain mediation between marital conflict and coparenting. These findings support the spillover theory and provide relevant empirical evidence and advance our understanding of parental functioning on child smartphone dependence within the Chinese culture.

Determination of six core components from Mahuang Xuanfei Zhike syrup in rat plasma and tissues by UPLC-MS/MS: Application to a pharmacokinetics and tissue distribution study.

Mahuang Xuanfei Zhike (MXZ) syrup, a Chinese patent medicine, has been widely used in the clinical treatment of cough. However, there is no reported method for the quantitative analysis of the effective components of MXZ syrup in biological samples. In this study, the effective components of MXZ syrup were screened by network pharmacology and molecular docking technology. A sensitive and rapid ultra-performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) method was established to test the active components of MXZ syrup in rat plasma and tissue homogenates, including ephedrine, amygdalin, chlorogenic acid, harpagoside, forsythin and forsythoside A. Chromatographic separation was performed on a Waters Acquity UPLC HSS T3 column (2.1 × 50 mm, 1.8 µm) and the mass analysis was conducted using a Waters Xevo TQ mass spectrometer using multiple reaction positive and negative ion simultaneous monitoring mode. The results showed that the linearity ranged from 0.3 to 409.4 ng/ml. The extraction recoveries were all <8.33%, and the matrix effects were all <8.45, which met the requirements. The pharmacokinetic and tissue distribution results indicated that the main active components of MXZ syrup were absorbed quickly and eliminated slowly in vivo, and there may be a reabsorption process.

Parent-child relationship and problematic smartphone use among chinese adolescents: a moderated mediation model.

To explore the influence and mechanism of parent-child relationship on adolescents' problematic smartphone use, a sample of 3355 Chinese adolescents (M age=16.93, SD = 0.49, range: 14-19 years old; 48% boys) is recruited to measure parent-child relationship, problematic smartphone use, personal growth initiative, and school belonging. The results are as follows. (1) After controlling for gender, age and time spent online per day, parent-child relationship is negatively correlated with problematic smartphone use, and the negative association between parent-child relationship and problematic smartphone use is mediated by the personal growth initiative. (2) The association between parent-child relationship and problematic smartphone use, the association between parent-child relationship and personal growth initiative, and the association between personal growth initiative and problematic smartphone use are all moderated by school belonging and are stronger in adolescents with a high level of school belonging. The present study highlights the mediating role of personal growth initiative and the moderating role of school belonging in the association between parent-child relationship and problematic smartphone use. This study also contributes to a better understanding of the effects, paths, and conditions of parent-child relationship on the problematic smartphone use of adolescents and provides constructive suggestions for preventing adolescents' problematic smartphone use in the mobile Internet era.

Barbier Hyperbranching Polymerization-Induced Emission from an AB-Type Monomer.

Luminescent polymer materials have gained considerable research efforts in the past decades and are generally molecular designed by extending the π system of the polymer main chain or by incorporating chromophores into the polymer chain, which suffer from poor solubility, difficult synthesis, or multi-step procedures. Meanwhile, according to the step-growth polymerization theory, synthesis of hyperbranched polymers from an AB-type monomer is still challenging. Herein, we report a one-pot synthesis of nonconjugated luminescent hyperbranched polymer material via Barbier hyperbranching polymerization-induced emission (PIE) from an AB-type monomer. The key step in the realization of the hyperbranched polymer is bi-functionalization of a mono-functional group. Through a Barbier reaction between an organohalide and an ester group in one pot, bi-functionalization of mono-functional ester is realized through two-step nucleophilic additions, resulting in hyperbranched polytriphenylmethanols (HPTPM). Attributed to through-space conjugation and inter- and intramolecular charge-transfer effects induced by polymer chain, nonconjugated HPTPMs are PIEgens, which are tunable by monomer structure and polymerization time. When all phenyl groups are rotatable, HPTPM is aggregation-induced emission type PIEgen. Whereas, it is aggregation-caused quenching type PIEgen if some phenyl groups are rotation forbidden. Further potential applications of PIEgen are in the fields of explosive detection and artificial light harvesting systems. This work, therefore, expands the monomer library and molecular design library of hyperbranched polymers through "bi-functionalization of mono-functional group" strategy, which eventually expands the preparation library of nonconjugated luminescent polymer materials through one-pot PIE from nonemissive monomer.

Living Covalent-Anionic-Radical Polymerization via a Barbier Strategy.

The developments of the living alkene polymerization method have achieved great progress and enabled the precise synthesis of important polyalkenes with controlled molecular weight, molecular weight distribution, and architecture through an anionic, cationic or radical strategy. However, it is still challenging to develop a living alkene polymerization method through an all-in-one strategy where anionic and radical characteristics are merged into one polymerization species. Here, a versatile living polymerization method is reported by introducing a well-established all-in-one covalent-anionic-radical Barbier strategy into a living polymerization. Through this living covalent-anionic-radical Barbier polymerization (Barbier CARP), narrow distributed polystyrenes, with D as low as 1.05, are successfully prepared under mild conditions with a full monomer conversion by using wide varieties of organohalides, for example, alkyl, benzyl, allyl, and phenyl halides, as initiators with Mg in one pot. This living covalent-anionic-radical polymerization via a Barbier strategy expands the methodology library of polymer chemistry and enables living polymerization with an unconventional polymerization mode.

Idarucizumab reverses dabigatran-induced anticoagulation in treatment of gastric bleeding: A case report.

BACKGROUND: The drug instructions for dabigatran recommend adjusting the dosage to 110 mg twice daily for patients with bleeding risk, and performing at least one renal function test per year for patients with moderate renal impairment. However, owing to chronic insidiously worsening renal insufficiency, dabigatran can still accumulate abnormally, necessitating therapy with idarucizumab to reverse the anticoagulation due to severe erosive gastritis with widespread stomach mucosal bleeding. CASE SUMMARY: A 76-year-old woman with a history of atrial fibrillation who took dabigatran 110 mg twice daily as directed to lessen the chance of stroke, was transported to the hospital with hematemesis and melena. Laboratory findings revealed severe life-threatening, blood-loss-induced anemia with a hemoglobin (Hb) level of 41.0 g/L and marked coagulation abnormalities with thrombin time (TT) > 180 s, most likely caused by dabigatran-induced metabolic disorder. Aggressive acid suppressive, hemostatic, and blood transfusion therapy resulted in the misconception that the bleeding was controlled, with subsequent rebleeding. Idarucizumab was administered in a timely manner to counteract dabigatran's anticoagulant impact, and 12 h later, TT was determined to be 17.4 s, which was within the normal range. Finally, the patient had no active bleeding signs and laboratory findings showed an Hb level of 104 g/L and TT of 17.7 s. CONCLUSION: Renal function, coagulation function, and dabigatran concentration should be regularly monitored in older patients. Proton pump inhibitor and dabigatran coadministration is still controversial in preventing upper gastrointestinal tract bleeding.

Bowknot-like Zr/La bimetallic organic frameworks for enhanced arsenate and phosphate removal: Combined experimental and DFT studies.

Hazardous oxyanions in water bodies are potentially toxic to aquatic life, and the coexistence of multiple anions aggravates the toxicity. Herein, bowknot-like Zr/La bimetallic organic frameworks (Zr/La-BTC) were developed with superior hazardous oxyanion adsorption capacities, i.e., approximately 102 mg/g for arsenate and 159 mg/g for phosphate, respectively. The molar ratio of Zr to La in Zr/La-BTC plays a significant role in the structure and the adsorption efficiencies. Notably, the experiment-derived adsorption capacities of various Zr/La-BTC samples were consistent with their adsorption energies calculated by density-function theory (DFT). Further mechanism analysis revealed that coordination of Zr/La atoms with the target anion groups occurred during adsorption. The positive shift of binding energies in La 3d and Zr 3d XPS spectra and Bader charge analysis unveiled that back-donation interactions dominated the adsorption process. The reliable adsorption selectivity and reusability of 0.1Zr/La-BTC were verified with anion competition experiments and four adsorption-desorption cycles. Overall, this study provides significant insight into the design of high-performance bimetallic organic frameworks for the enhanced removal of hazardous oxyanions from water.

Quantification of Liver Fat Content after Radiofrequency Ablation for Liver Cancer: Correlation with Hepatic Perfusion Disorders.

PURPOSE: To quantitatively investigate the correlation between liver fat content and hepatic perfusion disorders (HPD) after radiofrequency ablation (RFA) for liver cancer using magnetic resonance imaging (MRI)-determined proton density fat fraction (PDFF). MATERIALS AND METHODS: A total of 150 liver cancer patients underwent liver MRI examination within one month after RFA and at four months after RFA. According to the liver fat content, they were divided into non-, mild, moderate, and severe fatty liver groups. The liver fat content and hepatic perfusion disorders were determined using PDFF images and dynamic contrast-enhanced MRI images. The relationship between the liver fat content and HPD was investigated. RESULTS: At the first postoperative MRI examination, the proportion of patients in the nonfatty liver group with hyperperfused foci (11.11%) was significantly lower than that in the mild (30.00%), moderate (42.86%), and severe fatty liver (56.67%) groups (p < 0.05), whereas the proportions of patients with hypoperfused foci (6.67%, 7.5%, 5.71%, and 6.67%, respectively) were not significantly different among the four groups (p > 0.05). In the nonfatty liver group, the liver fat content was not correlated with hyperperfusion abnormalities or hypoperfusion abnormalities. By contrast, in the three fatty liver groups, the liver fat content was correlated with hyperperfusion abnormalities but was not correlated with hypoperfusion abnormalities. At the second postoperative MRI examination, six patients in the nonfatty liver group were diagnosed with fatty liver, including two patients with newly developed hyperperfusion abnormalities and one patient whose hypoperfusion abnormality remained the same as it was in the first postoperative MRI examination. CONCLUSION: There was a high correlation between the liver fat content and hyperperfusion abnormalities after RFA for liver cancer. The higher the liver fat content was, the higher the was risk of hyperperfusion abnormalities. However, there was little correlation between liver fat content and hypoperfusion abnormalities, and the increase in postoperative liver fat content did not induce or alter the presence of hypoperfused foci.

Development of an immune-related prognostic model for pediatric acute lymphoblastic leukemia patients.

BACKGROUND: Acute lymphoblastic leukemia (ALL) is the most common hematological malignancy in pediatrics, and immune-related genes (IRGs) play crucial role in its development. Our study aimed to identify prognostic immune biomarkers of pediatric ALL and construct a risk assessment model. METHODS: Pediatric ALL patients' gene expression data were downloaded from Therapeutically Applicable Research to Generate Effective Treatments (TARGET) database. We screened differentially expressed IRGs (DEIRGs) between the relapse and non-relapse groups. Cox regression analysis was used to identify optimal prognostic genes, then, a risk model was constructed, and its accuracy was verified in different cohorts. RESULTS: We screened 130 DEIRGs from 251 pediatric ALL samples. The top three pathways that DEIRGs may influence tumor progression are NABA matrisome-associated, chemotaxis, and antimicrobial humoral response. A set of 84 prognostic DEIRGs was identified by using univariate Cox analysis. Then, Lasso regression and multivariate Cox regression analysis screened four optimal genes (PRDX2, S100A10, RORB, and SDC1), which were used to construct the prognostic risk model. The risk score was calculated and the survival analysis results showed that high-risk score was associated with poor overall survival (OS) (p = 3.195 × 10-7 ). The time-dependent survival receiver operating characteristic curves showed good prediction accuracy (Area Under Curves for 3-year, 5-year OS were 0.892 and 0.89, respectively). And the predictive performance of our risk model was successfully verified in testing cohort and entire cohort. CONCLUSIONS: Our prognostic risk model can effectively divide pediatric ALL patients into high-risk and low-risk groups, which may help predict clinical prognosis and optimize individualized treatment.

Core binding factor acute myeloid leukemia: Advances in the heterogeneity of KIT, FLT3, and RAS mutations (Review).

Core binding factor (CBF) is a heterodimer protein complex involved in the transcriptional regulation of normal hematopoietic process. In addition, CBF molecular aberrations represent approximately 20% of all adult Acute Myeloid Leukemia (AML) patients. Treated with standard therapy, adult CBF AML has higher complete remission (CR) rate, longer CR duration, and better prognosis than that of AML patients with normal karyotype or other chromosomal aberrations. Although the prognosis of CBF AML is better than other subtypes of adult AML, it is still a group of heterogeneous diseases, and the prognosis is often different. Recurrence and relapse-related death are the main challenges to be faced following treatment. Mounting research shows the gene heterogeneity of CBF AML. Therefore, to achieve an improved clinical outcome, the differences in clinical and genotypic characteristics should be taken into account in the evaluation and management of such patients, so as to further improve the risk stratification of prognosis and develop targeted therapy. The present article is a comprehensive review of the differences in some common mutant genes between two subtypes of CBF AML.

Research on the Influence of Cosolvent on the Determination of the Contamination Degree of Jet Fuel.

The effect of cosolvent on trace free water in the determination of the contamination degree of jet fuel was investigated. The interference of trace free water on the automatic particle counter can be eliminated by adding isopropanol as a cosolvent to the measured oil sample. Isopropanol can dissolve trace free water in oil. Addition of isopropanol could stabilize the pollution grade of particles with size ≥30 µm (c) at the same level, which is most obviously affected by free water without isopropanol. The standard uncertainty u(X 1) is slightly reduced with the addition of isopropanol, and the repeatability and accuracy of the automatic particle counting method are obviously improved. The results show that isopropanol should be added as a cosolvent to eliminate the interference of free water when the contamination degree of jet fuel oil samples with obvious free water is determined by the automatic particle counting method.