【正文】 orous films with specific pore ratings, which selectively separate a fluid from its ponents. There are four established membrane separation processes, including microfiltration (MF), ultrafiltration (UF), reverse osmosis (RO) and nanofiltration (NF). RO separates dissolved and ionic ponents, MF separates suspended particles, UF separates macromolecules and NF is selective for multivalent ions. MF and UF can be used as a standalone technology for treating industrial wastewater, but RO and NF are usually employed in water desalination. Membrane technology operates two types of filtration processes, crossflow filtration or deadend filtration, that can be a pressure (or vacuum)driven system. Microfiltration/ultrafiltration MF has the largest pore size (–3 181。調(diào)查的飲用水和衛(wèi)生設施在農(nóng)村調(diào)查數(shù)據(jù)說明需要更多的數(shù)據(jù)在世界人口最多的國家在理解全球模式的家庭水處理。其他治療方法 ,如。 一個小規(guī)模的調(diào)查在安徽省 ,收集了 35個家庭存儲水樣本中隨機選擇的家庭在三個縣報道 ,合規(guī)率對總大 腸桿菌群 ( 1克隆形成單位 / 100 mL)的水儲存在家里只有 39%。如果這 4%患病率估計家庭水過濾應用于總中國大陸城市人口 億 ,這表明 2490 萬人口的過濾水。家庭水過濾器中 ,越來越多地使用在城市地區(qū)的中國。 盡管原始數(shù)據(jù)仍然沒有公開可用的 ,總結(jié)的官方報告顯示 ,%的農(nóng)村家庭煮水喝 ,治療前 %他們的水 (不含沸騰 )。共有 65839 戶家庭接受了采訪 ,6948 年供應系統(tǒng)、地下水和地表水水樣為物理化學參數(shù)和總大腸菌群。我們發(fā)現(xiàn) 417 中文參考文獻。盡管缺乏家庭水處 理可訪問的數(shù)據(jù)在英語語言 ,可能存在其他調(diào)查 ,進行了由中國政府而不是通過國際系統(tǒng) ,如多個指標 ,結(jié)果發(fā)表調(diào)查中只有中文。這些調(diào)查結(jié)果已經(jīng)被包括在世界衛(wèi)生組織 /聯(lián)合國兒童基金會聯(lián)合監(jiān)測項目報告。他們討論了地理限制的全球評估 ,特別是缺乏數(shù)據(jù)在中國最大的國家人口。賴特 地理和環(huán)境 南安普頓大學 大學路 南安普頓 SO17 1 bj、英國 電子郵件 :() 3 Gundry stephen w . +作者從屬關(guān)系 水和衛(wèi)生研究中心 布里斯托大學 林地道路 布里斯托爾 BS8 英國 電子郵件 :() 這項研究由比 爾和梅林達蓋茨基金會 ,在格蘭特參考 48599(Aquatest 2:交付一個低成本水試驗對于發(fā)展中國家 )。s most populous nation in understanding global patterns of household water treatment. It further underscores the need articulated by Rosa and Clasen to understand the effectiveness and use of boiling in nonintervention settings. 中國家庭水處理 1 楊宏 地理和環(huán)境 南安普頓大學 大學路 南安普頓 SO17 1 bj、英國 電子郵件 :) 2 吉姆s Fund Joint Monitoring Program report. However, none of these survey questionnaires covered household water treatment. Despite the lack of data on home water treatment accessible in the English language, it is possible that other surveys exist that have been conducted by the Chinese government rather than through international systems, such as the Multiple Indicator Cluster Survey, with results published in Chinese only. We searched the bibliographic database Chinese National Knowledge Infrastructure by using the Chinese key words for “household” and “water” and “treatment/disinfection”. We found 417 Chinese language references. After screening the titles and abstracts of all references and the content of an additional 197 references, we found one paper reporting the national summary results of the Investigation of Drinking Water and Sanitation in the Rural Areas conducted jointly by the Ministry of Health and the National Committee for Patriotic Public Health Campaign, People39。Household Water Treatment in China ? Hong Yang Geography and Environment University of Southampton University Road Southampton SO17 1BJ, United Kingdom Email: () ? Jim A. Wright Geography and Environment University of Southampton University Road Southampton SO17 1BJ, United Kingdom Email: () ? Stephen W. Gundry Author Affiliations Water and Health Research Centre University of Bristol Woodland Road Bristol BS8 1TH, United Kingdom Email: () This study was supported by the Bill amp。 Melinda Gates Foundation, under grant reference 48599 (Aquatest 2: Delivery a low cost water test for developing countries). Dear Sir: We read with interest the article by Rosa and Clasen about the prevalence of household water treatment in lowine and middleine countries. They discussed the geographic limitations of their global estimation, especially the lack of data for the largest national population in China. Several surveys covering water and sanitation have been undertaken in China in recent decades, such as the World Health Survey, the Global Water Supply and Sanitation Assessment 2021, and the Multiple Indicator Cluster Survey. These survey results have already been included in the World Health Organization/United Nations Children39。s Republic of China, during August 2021–November this nationally representative multistage cluster survey of rural areas, 6,948 sites were surveyed in 6,590 villages across all 31 provinces, autonomous regions, and municipalities in mainland China. A total of 65,839 households were interviewed and 6,948 supply system, groundwater and surface water samples were tested for physicochemical parameters and total coliforms. The interviews included two questions on home water treatment: ? “What is your usual drinking practice? 1) Drink raw water, 2) Drink boiled water” and ? “Do you treat (other than boiling) the household?s water? Yes or No”. Although the raw data are still not publicly available, the summary of the official report indicated that % of rural households boiled their water before drinking and % treated their water (excluding boiling). Given that the mainland Chinese rural population was estimated to be million in 2021,this finding suggests that the population boiling household water is million and the population using other forms of home water treatment is million in rural China. Household water filters are increasingly used in urban areas of China. Although there are no reported household survey data for urban areas, one report estimated that 3–5% of the urban population used household water this 4% prevalence estimate for household water filtration is applied to the total mainland Chinese urban population of million,this suggests a population of million filtering their water. Including these estimates for China, the global population from lowine and middleine countries boiling household water doubles from to billion, and the population using treated household water increases to at least billion. A smallscale survey in Anh