Quality and Quantity Assessment of the Water Repellent Properties of Functional Clothing Materials after Washing

The aim of the research was to evaluate the changes in the surface properties of five functional clothing materials with water-repellent finishes (including PFC-free finish) after 1, 5, and 10 washes with three detergents. A new approach to the interpretation of the water-repellent properties of textile materials is presented, based on two techniques, i.e., the spray test method and contact angle measurements. The results showed that washing materials with hydrophobic finishes can cause significant changes in their properties, which are mainly dependent on the composition and structure of the material, as well as the type of hydrophobic finish. The PFC-free finish is the least resistant to washing. For all materials with PFC finishes, the water repellency depends on the fluorine content on the surface and fabric topography. It was also found that increasing washing frequency resulted in a gradual decrease in water repellency. The loss of water repellency below an acceptable level (Grade 3) occurred after the fifth washing for all materials. Significant differences in the interpretation of the results of the spray test and contact angle measurements were observed. Using these methods separately provides information on the changes in the surface properties of the tested materials; however, their parallel application allows for obtaining complementary data, which is important for the proper interpretation of results.     

上海市浦东新区自动售水机卫生状况及影响因素分析

[目的]了解自动售水机选址与外表卫生状况,为改善自动售水机卫生现状提出建议。[方法]以上海市浦东新区辖区内所有的自动售水机为对象,随机抽取236台对其选址、遮雨棚设置、机器外表整洁及完整与否、出水口防护门、出水管口及取水凹口周壁等内容开展卫生学调查。[结果]调查结果表明,17．37％的自动售水机设置点周围10m范围内存在污染源;11．44％的自动售水机设置点周围地面排水不畅,有积水;2．54％的自动售水机未安装防护门和8．47％的自动售水机防护门已损坏不能正常使用;30．93％的自动售水机器外表存在各种污迹,同时有2．12％的受调查机器外壳已破损;受调查自动售水机的出水管口、取水凹口顶壁、内侧壁的细菌总数、霉菌、大肠菌群的检出率分别为78．81％、39．41％、48．30％;75．85％、81．78％、90．68％和21．19％、5．93％、15．25％。同时,保持自动售水机周边环境整洁、设置取水凹口防护门并保持正常运作、出水管外套有套管对减少或减轻上述部位的污染有着显著的意义。[结论]自动售水机经营单位应加强设备管理,注意维护设备的外表整洁,定期对取水凹口周壁、出水管口进行清洗、消毒;同时,要注意保持设备周边环境的整洁,并应在设备上加装取水凹口防护门、出水管套管等装置,维护其正常运作和洁净。     

湖泊水源地突发苯酚污染底泥表层扩散吸附研究

本实验重点关注湖泊水源地突发性苯酚污染事故中底泥表层的污染情况,建立数学模型并通过模拟实验,对污染发生后36 h底泥中苯酚浓度的连续监测,研究了污染时间、底泥深度、温度和pH对扩散的影响,验证了与上述四个因素相关的数学模型.结果表明:由于底泥对苯酚存在吸附—脱吸作用,需要对扩散系数进行修正,并且对于不同的底泥组成其修正...     

淄博市生活饮用水中硝酸盐暴露及其健康风险的时空分布特征

目的 对饮用水硝酸盐进行健康风险评估,为水质干预决策提供技术依据。 方法 对2016~2020年淄博市2 575份城乡饮用水样品检测硝酸盐含量,采用我国《化学物质环境健康风险评估技术指南》(WS/T 777-2021)的环境健康风险评价模型,分析不同年度、不同监测点类型、不同水源、不同处理方式的硝酸盐含量和非致癌健康风险的时空分布特征。 结果 2016~2020年共检测水样2 575份,硝酸盐超标率为10.76%。饮用水硝酸盐含量具有空间聚集性,高值主要集中在沂源县中部和东部、博山区西南部,低值集中在高青县和桓台县。饮用水硝酸盐含量和非致癌健康风险总体呈现逐年升高趋势,农村水高于城区水、地下水高于地表水、未处理水高于处理水。5年总体平均非致癌风险为0.21,对人体产生的非致癌风险较低;最高非致癌风险为1.99,主要集中在沂源县,对人体存在长期暴露的非致癌健康风险。 结论 淄博市局部区域饮用水硝酸盐污染较严重,存在非致癌健康风险,应引起关注并采取水质干预措施。     

六安市某高职院校学生健康饮水知识调查

目的了解高职院校学生饮水知识的知晓情况,为在学生中开展健康饮水知识教育提供科学依据。方法采用分层整群抽样的方法,抽取皖西卫生职业学院中专、大专共计537名学生,采取自行设计的问卷进行饮水相关知识调查。结果调查对象中仅有9.9%的学生知道每日最少饮水量为1 200 mL;8%的调查对象不知道白开水是最健康的饮品;仅有26.1%的学生知道饮水不足会引起认知功能发生改变;44.9%的学生认为感到口渴时才饮水最利于健康;对于一次饮水量200 mL为宜,调查对象的知晓率为50.1%。高职院校学生总体健康饮水知识的知晓率,男生低于女生、中专生低于大专生、独生子女低于非独生子女。结论调查对象饮水知识不全面,需采取适宜措施,有针对性开展健康饮水知识教育,提高其健康饮水意识。     

The Relationship between Fluid Milk,Water, and 100% Juice and Health Outcomes among Children and Adolescents

Beverages can provide improved nutrient intake and hydration, but also pose concerns related to overnutrition or contamination for children and adolescents who are in a time of critical growth. This narrative review aims to understand the impact of milk, 100% juice, and water consumption on health-related outcomes in youth. The literature review conducted used PubMed, Web of Science, and CABI global. Forty-five research articles met the quality criteria and were included. Health organization and governmental resources were also reviewed to identify current intake and consumption recommendations. All beverages in this review were associated with a variety of desirable and undesirable findings that spanned over 40 different health outcomes. Most studies that assessed milk lacked clear distinction between milk type (flavored vs. unflavored) or fat percentage, making it difficult to understand the impact of milk consumption. The relationship between milk intake and anthropometric-related outcomes were mixed within and across studies. Water was consistently associated with better hydration, while 100% juice and flavored milk intake was associated with more desirable dietary patterns or nutrients that children are currently not consuming adequate amounts of. The implications of these findings were discussed in the context of the National School Lunch Program (NSLP), while considering the impact of issues such as contaminated water and lactose intolerance. This review suggests that water may be an optimal default beverage option in the NSLP to promote hydration and accommodate beverage preferences for those with lactose intolerance.     

Sulfate Freeze–Thaw Resistance of Magnesium Potassium Phosphate Cement Mortar

Concrete facilities in the severe-cold areas of western China (salt lake environments and heavy saline soils) are seriously damaged by the multiple corrosion effects of freeze–thaw cycles and sulfate corrosion. Magnesium phosphate cement (MPC) cement-based material has become an ideal concrete structural component because of its superior performance. Because concrete structural repair materials are used in heavy-corrosion environments, their durability in those environments should also be considered. Regarding the salt-freezing resistance of MPC, the existing studies have all used a NaCl solution as the heat transfer medium. In addition to chlorine salt, sulfate, especially Na₂SO₄, is also common in typical use environments such as oceans, salt lakes, and groundwater. To evaluate the sulfate freeze–thaw resistance of potassium magnesium phosphate cement (MKPC) mortar, in this study the strength development, weight loss, and water absorption of MKPC mortar specimens subjected to different freeze–thaw cycles were tested and compared with those for Portland cement (P.O) mortar specimens of the same strength grade. The results showed that the P.O mortar specimen completely lost its strength after 75 cycles of rapid water freezing and thawing and 50 cycles of sodium sulfate solution (5%) freezing and thawing. However, the residual strength rating of the MKPC mortar specimen after 75 cycles of water freezing and thawing and 100 cycles of sodium sulfate solution freezing and thawing was higher than 75%. After 50 rapid freeze–thaw cycles in water and a 5% Na₂SO₄ solution, the P.O mortar specimen’s mass loss exceeded the 5% failure standard, whereas the mass loss of the MKPC mortar specimens was much less than 5%. Before the freeze–thaw cycles, the water absorption of the P.O mortar specimen was close to 8 times that of the MKPC mortar specimen, and after 50 water freeze–thaw cycles and 25 sulfate solution freeze–thaw cycles, the water absorption reached 4.88% and 5.68%, respectively. However, after 225 freeze–thaw cycles in water and the sulfate solution, the water absorption rates of MKPC mortar specimens were 2.91% and 2.51% respectively. The test and analysis results show that the freeze–thaw resistance of MKPC mortar was much higher than that of Portland cement mortar specimens. Those results provide a prerequisite for applying and expanding the use of MKPC-based materials in severe-cold areas of western China (salt lake and heavily saline soil environments).     

Quantification of the Hardened Cement Paste Content in Fine Recycled Concrete Aggregates by Means of Salicylic Acid Dissolution

Adherent hardened cement paste attached to recycled concrete aggregates (RCA) generally presents a higher porosity than natural aggregates, which induces a lower porosity in the properties of RCA. The characterization of the adherent hardened cement paste content (HCPC) in the fine RCA would promote better applications of RCA in concrete, but the determination of HCPC in fine RCA is not well established. A simple method based on salicylic acid dissolution was specifically developed to quantify the HCPC in RCA, especially for RCA containing limestone aggregates. The results demonstrated that the soluble fraction in salicylic acid (SFSA) was equal to the HCPC for white cement and slightly lower for grey Portland cement, which was also confirmed by a theoretical approach using modelling the hydration of cement paste with the chemical equations and the stoichiometric ratios. The physical and mechanical properties of RCA (e.g., water absorption) were strongly correlated to the SFSA. For industrial RCA, SFSA did not give the exact value of HCPC, but it was sufficient to correlate HCPC with the other properties of RCA. The water absorption could be estimated with good accuracy for very fine RCA (laboratory-manufactured RCA or industrial RCA) by extrapolating the relationship between water absorption and HCPC, which is very important for concrete formulation.     

反复吸入2.3%七氟烷对幼年大鼠学习记忆与乙酰胆碱酯酶活性的影响

目的：观察幼年大鼠反复吸入2.3%七氟烷对学习记忆能力的影响.方法：将健康雄性SD大鼠60只随机均分为6组,Con1组、Con3组、Con5组：每天同一时间吸氧1 h,流量0.5 L/min,分别吸1、3、5 d;Sev1组、Sev3组、Sev5组：每天同一时间吸入2.3%七氟烷和流量0.5 L/min氧气的混合气体1 h,分别吸1、3、5 d.末次给药7 d后,进行水迷宫实验,观察大鼠达标所需训练次数、逃避潜伏期及进入盲端的次数,行为学实验后测定乙酰胆碱酯酶活性.结果：与Con1、Con3、Con5组比较,Sev1、Sev3、Sev5组大鼠达标所需训练次数、逃避潜伏期、进入盲端次数以及乙酰胆碱酯酶活性差异均无统计学意义（P〉0.05）.结论：持续5 d,每天吸入2.3%七氟烷1 h,末次给药7 d后对于幼年大鼠空间辨别学习记忆功能无明显影响.     

Protective effects of penehyclidine hydrochloride on acute lung injury caused by severe dichlorvos poisoning in swine

Background Organophosphate poisoning is an important health problem in developing countries which causes death mainly by inducing acute lung injury. In this study, we examined the effects of penehyclidine hydrochloride （PHC）, a selective M-receptor inhibitor, on dichlorvos-induced acute lung injury in swine. Methods Twenty-two female swines were randomly divided into control （n=5）, dichlorvos （n=6）, atropine （n=6）, and PHC （n=5） groups. Hemodynamic data, extravascular lung water index （EVLWI）, and pulmonary vascular permeability index （PVPI） were monitored; blood gas analysis and acetylcholinesterase （AchE） levels were measured. PaO2/FiO2, cardiac index （CI）, and pulmonary vascular resistance indices （PVRI） were calculated. At termination of the study, pulmonary tissue was collected for ATPase activity determination and wet to dry weight ratio （W/D） testing 6 hours post-poisoning. TUNEL assay, and Bax, Bcl-2, and caspase-3 expression were applied to pulmonary tissue, and histopathology was observed. Results After poisoning, PHC markedly decreased PVRI, increased CI more effectively than atropine. Anticholinergic treatment reduced W/D, apoptosis index （AI）, and mitigated injury to the structure of lung; however, PHC reduced AI and caspase-3 expression and improved Bcl-2/Bax more effectively than atropine. Atropine and PHC improved ATPase activities; a significant difference between groups was observed in Ca2＋-ATPase activity, but not Na＋-K＋-ATPase activity. Conclusions The PHC group showed mild impairment in pathology, less apoptotic cells, and little impact on cardiac function compared with the atropine group in dichlorvos-induced acute lung injury.