Days In Drinking Water Research Articles

Predicting the urban water demand by equipping intelligent-based methods with discrete wavelet transform function

To satisfy the consumer demand, urban infrastructures are generally designed. The water distribution network (WDN) is one of the most important urban infrastructures in which optimal design and operation of it is essential during the operation period. For this purpose, in this research, artificial intelligence and data mining methods, including genetic programming (GP), gene expression programming (GEP), artificial neural network (ANN), and discrete wavelet transform function, are used to predict the daily drinking water consumption values of WDN. For this purpose, a dataset of temperature, precipitation, humidity, and daily water value of Najaf-Abad city in Iran is used during year 2014 to 2019. Here, hybrid models named W-GEP, W-GP, W-ANN, are proposed by equipping GEP, GP, and ANN with a wavelet transform function. In addition, two formulations are proposed for each model. Performance of proposed methods is investigated by determining R2, RMSE, and NSE statistical indices. For the training data of the W-GP model, the RMSE, NSE, and R2 values are 2810.46 (m3/day), 0.85, and 0.85, respectively, while for test and validation data these values are 2638.92 (m3/day), 0.87, and 0.87, respectively. Results show the good performance of proposed methods. In addition, the discrete wavelet transform function improves the models’ performance, in which the best results obtained by using the W-GEP model.

Role of Rosmarinus officinalis Aqueous Extract in Relieving the Complications Associated with Ethylene Glycol-induced Urolithiasis in Male Rats

Background: Rosmarinus officinalis is considered one of the famous plants from ancient times for its therapeutic ability in many diseases, such as headache, spasms, brain disorders, and some pathological conditions associated with toxicity cases in the liver and kidneys. Aim: The current research has aimed, for the first time, to evaluate anti-urolithiatic effect of Rosmarinus officinalis aqueous extract (RMAE) on calcium oxalate stones formation in male rats and its possible therapeutic mechanisms of action. Evaluation of the polyphenols and flavonoid content in the extract was also performed. Methods: A calcium oxalate nephrolithiasis case was established in rats by adding ethylene glycol (1%) to the rats' daily drinking water for a duration of one month. Treatment was achieved by oral co-administration of RMAE to rats administrated ethylene glycol. Results: Phytochemical results showed that LC/MS-MS analysis led to the identification of 37 compounds in the phytoconstituent profile of RMAE. The biochemical results revealed significant improvement in serum kidney functions (urea, creatinine, and uric acid) in addition to restoring the calcium x phosphorous product and parathyroid hormone (PTH) levels in the plant-treated group compared to the non-treated one. The data have been supported by the significant decrease in lactate dehydrogenase enzyme (LDH) expression in the liver tissues, reflecting the decrease in oxalate synthesis in the liver compared to the non-treated group. Kidneys' histological examinations showed the absence of oxalate crystals in the treated group and the immunohistochemical findings of osteopontin (OPN) protein revealed the impact of RMAE on OPN expression in kidney tissues. Improvements in the femur bone fractures and the parathyroid gland in the treated group were also noticed during microscopic examinations. Conclusion: The anti-lithiatic effect of the extract was attributed to its influence on serum phosphate, serum PTH, and OPN levels in kidney tissues and decreasing synthesis of LDH in liver tissues in addition to the prevention of secondary disease incidences, such as secondary hyperparathyroidism and cardiovascular diseases. On the other hand, the plant's considerable content of phenolics and flavonoids has been found to play a role in controlling kidney stone progression episodes.

Exergy Optimization of a Hybrid Multi Evaporative Desalination Plant powered by Solar and Geothermal Energy

Abstract An energy and exergy analysis has been conducted on a hybrid desalination system powered by solar energy using vacuum collectors and geothermal energy. This system is specifically designed to operate under the environmental conditions of southern Tunisia. The desalination plant is mainly constituted by a solar collector field, a thermal energy storage system, a Multiple Effect Distillationunit (MED) system, an evaporative condenser, and a geothermal energy recovery system. The analysis is performed using computational code established with EES software. A parametric study is conducted to examine the effects of key operating parameters on plant performances. The operating mode is determined for winter and summer seasons. Obtained results show that thermal storage system provides thermal power permitting continuous operation for about 8 hours during the nighttime period. The storage tank is the most contributor in exergy destruction with approximately 4.3 kW in winter and 5.5 kW in summer followed by the solar collector field of about 3.6 kW in winter and 3.8 kW in summer. The exergy efficiency of the desalination effects reaches 70 % in winter and 75 % in summer. The daily production of drinking water is about 12 m3/day in winter and 14 m3/day in summer. This meets the daily drinking water needs of around 3000 persons.

Implementasi Kebijakan Standar Pelayanan Minimal Pemenuhan Kebutuhan Pokok Air Minum di Kabupaten Paser

The application of the Minimum Service Standard policy for Fulfilling Daily Drinking Water Basic Needs in Paser Regency has followed the applicable technical standards, both from the Ministry of Public Works and Public Housing, as well as from regulations issued by the Regional Government of Paser Regency itself. But actually, it is necessary to identify what are the factors that support and hinder the implementation of SPM policies. From the results of data analysis, it was found that the process of implementing the MSS policy for the drinking water sub-sector was still not under technical standards because the basic data used in calculating service needs did not refer to the local BPS Susenas data, and there was no determination of priorities and targets for implementing SPM. The supporting factors identified included: Policy standards and targets, budgetary support, organizational internal and external communications, suitability of the duties and functions of the DPUTR in Human Settlements (organizational characteristics), positive responses and support from the community, a relatively conducive political situation, full support (response) from implementers/employees, and the level of implementer tendencies were quite high and positive. Meanwhile, the inhibiting factors include the lack of number and competence of employees in the implementing organization (Cipta Karya Division of the Paser Regency DPUTR), the unstable social and economic conditions of Paser Regency, and the low level of understanding of SPM policy implementers in the drinking water sub-sector.

Early Detection Patterns Of Chronic Kidney Disease Based On Differences In Individual Health Status In Kendari City

Background: The prevalence of chronic kidney disease (CKD) was small but it continued to increase every year in Kendari City. The patients were difficult to monitor. The aim of this research is to formulate an early detection pattern for CKD based on differences in individual health status in Kendari City. Methods: This quantitative research used a cross sectional study design which was conducted at 4 Community Health Centers and 3 Hospitals in Kendari City, Southeast Sulawesi, Indonesia. Recruited 136 respondents aged between 24-70 years. Data collection by interviews with questionnaires. The dependent variable is health status, and the independent variables include behavior, psychological environment, stress and genetics. Data analysis used chi square statistical tests, crosstabulation and multinomial logistic regression. Results: There is a significant difference in drinking water consumption behavior of less than 1000 ml a day (p<0.0001, OR=1.56, B=-20.276), calorie intake of less than 1534 calories a day (p<0.05, OR=2.13, B=-19.969 ), physical activity (p<0.05, OR=5.7, B=1.735), medication adherence (P<0.01, OR=0.4,B=1.999) and psychological stress environment (p<0.0001,OR=8.6, B=2.151 ) with the respondent's health status. Meanwhile, herbal consumption behavior (p=0.195) and genetic factors (p=0.813) did not show significant differences with individual health status. Conclusion: Early detection patterns for CKD can use the variable such as less drinking water consumption in healthy people and no obedient medication in single disease group. Using variables of less daily drinking water consumption and heavy physical activity in multiple diseases group, and less drinking water consumption, less physical activity, and moderate stress in CKD group.

The Role of Esophagography in the Diagnosis of Orthotopic Esophageal Squamous Cell Carcinoma in a Mouse Mode

Animal models play an irreplaceable role in pre-clinical studies of various tumors, mainly including xenogeneic/homograft subcutaneous tumor models. However, the subcutaneous transplanted tumor model is separated from the microenvironment of the primary tissue and fail to accurately simulate the growth of tumor cells in vivo. Therefore, orthotopic tumor models play an increasingly important role. For esophageal squamous cell carcinoma, chemotherapy-induced methods have successfully established mouse models of esophageal squamous cell carcinoma, but past experiments have found that it is still a challenge to confirm the success of the mouse model of esophageal cancer. The pathological diagnosis of the esophageal cancer tissue obtained from the killed mouse model remains the gold standard, but it also represents a lost opportunity to evaluate the efficacy of subsequent treatment. Notedly, esophagography is the primary examination for clinical patients with esophageal cancer. Therefore, the aim of this study is to evaluate whether esophagography can be used to establish a successful in situ mouse model of esophageal cancer. Referring to previous literature, we used the chemical drug 4-Nitroquinoline N-oxide (4-NQO) to induce orthotopic tumor model: A certain amount of 4-NQO was dissolved in propylene glycol to make a 2% stock solution, and then dissolved in 200ml of sterile water for the daily drinking water of mice. The water was kept in the dark and replaced once a week. After 16 weeks of induction, the drinking water was replaced by the same volume of sterile water and continued to be fed for 12 weeks. The mice were subsequently subjected to esophagography: First, the mice were fixed on a plastic plate, and the gavage needle was slowly inserted into the stomach, then slowly withdrawn out and gradually injected with meglumine diphosphate, with a total amount of 0.1-0.2ml. Then the radiolucent film was taken immediately, and three positions were selected, including the plain film, the standing film and the lateral film. After that, the mice were sacrificed and the esophagus of the mice was isolated and embedded in sections for pathological and immunohistochemical diagnosis. Finally, the results were compared with the imaging results. Based on the comparison of imaging and pathological results, we found that most of the esophageal segments with filling defects on esophagography were pathologically diagnosed as esophageal squamous cell carcinoma, and another part were diagnosed as esophageal papilloma. Compared with CT and MRI, esophagography has the advantages of simple operation and less consumable materials. We found that esophagography is a new non-invasive auxiliary diagnostic method for the successful establishment of an orthotopic mouse model of esophageal squamous cell carcinoma.

Polyester fiber bundle-based solar evaporator manufactured by dyeing for efficient desalination and zero liquid discharge

Polyester fiber bundle-based solar evaporator manufactured by dyeing for efficient desalination and zero liquid discharge

The Impact of Metformin on the Development of Hypothyroidism and Cardiotoxicity Induced by Cyclophosphamide, Methotrexate, and Fluorouracil in Rats.

Cyclophosphamide (CYP), methotrexate (MTX), and 5-fluorouracil (5-FU) are extensively utilized in the therapeutic management of various malignancies. It is noteworthy, however, that potential chemotherapy-related complications include the occurrence of hypothyroidism and cardiotoxicity. Metformin (MET) is a pharmacological agent for managing type 2 diabetes. It has been reported to mitigate certain toxic manifestations associated with chemotherapy. This study's primary objective is to investigate MET's protective effects against hypothyroidism and cardiotoxicity induced by CMF treatment. A total of forty male rats were allocated into four distinct groups, each consisting of ten rats per group. These groups were categorized as follows: saline, MET, CMF, and CMF + MET. The experimental group of rats were administered CMF via intraperitoneal injection, receiving two doses of CMF, and fed MET in their daily drinking water, with a 2.5 mg/mL concentration. Blood samples were collected into EDTA tubes for assessment of TSH, free and total (T4 and T3), troponin I, CK, and CK-MB levels utilizing Electrochemiluminescence Immunoassays (ECI). The saline and MET groups did not exhibit significant alterations in thyroid hormones or cardiotoxic biomarkers. In contrast, in the CMF group, there was a notable reduction in T4, FT4, T3, and FT3 levels but no significant changes in TSH levels; however, troponin I, CK, and CK-MB levels were notably elevated. MET co-treatment with CMF did not ameliorate these effects caused by CMF. In conclusion, CMF treatment induced hypothyroidism and cardiotoxicity in rats, but MET co-treatment did not rescue the reduction of thyroid hormones or the elevation of cardiotoxic biomarkers.

Metformin ameliorates liver fibrosis induced by congestive hepatopathy via the mTOR/HIF-1α signaling pathway

Congestive hepatopathy (CH) is a hepatic vascular disease that results in chronic liver congestion, which can lead to liver fibrosis. New uses of metformin have been discovered over the years. However, the function of metformin in congestive liver fibrosis is not yet fully understood. This study aimed to investigate the effect of metformin on liver fibrosis in a mouse model of CH. Partial ligation of the inferior vena cava (pIVCL) was used to establish a mouse model of liver congestion. Metformin (0.1%) was added to the daily drinking water of the animals, and the effect of metformin on liver tissue was studied after 6 weeks. Hepatic stellate cells (HSCs) were also stimulated with CoCl2 to investigate the inhibitory impact of metformin on the mammalian target of rapamycin (mTOR)/hypoxia-inducible factor-1α (HIF-1α) pathway. Metformin attenuated liver congestion; decreased the expression of collagen, fibronectin, α-smooth muscle actin (α-SMA), and HIF-1α; and ameliorated liver fibrosis in pIVCL mice. The proliferation and migration of HSCs were inhibited by metformin in vitro, which prevented α-SMA expression and restrained HSC activation. The expression levels of phosphorylated-mTOR, HIF-1α, and vascular endothelial growth factor were also decreased. Metformin inhibits CH-induced liver fibrosis. Functionally, this beneficial effect may be the result of inhibition of HSC activation and of the mTOR/HIF-1α signaling pathway.

Boosting interfacial solar steam generation by three-dimensional bilayer cellulose aerogels

Interfacial solar steam generation (ISSG) provides a sustainable approach of clean water production through desalination and water purification. It is still needed to pursue a fast evaporation rate, high-quality freshwater production, and low-cost evaporators. Herein, a three-dimensional (3D) bilayer aerogel was fabricated using cellulose nanofiber (CNF) as a skeleton filled with polyvinyl alcohol phosphate ester (PVAP), and carbon nanotubes (CNT) as a light absorbing material in the top layer. The CNF/PVAP/CNT aerogel (CPC) had broadband light absorption ability and exhibited an ultrafast water transfer rate. The lower thermal conductivity of CPC effectively confined the convert heat in the top surface and minimized heat loss. Additionally, a large amount of intermediate water caused by water activation decreased the evaporation enthalpy. Under 1 sun irradiation, the CPC-3 (3.0cm height of CPC) achieved a high evaporation rate of 4.02kgm-2 h-1 with an energy conversion efficiency of 125.1%. The additional convective flow and environmental energy made CPC achieve an ultrahigh evaporation rate of 11.37kgm-2 h-1, surpassing 673% of the solar input energy. More importantly, the continuous solar desalination and higher evaporation rate (10.70kgm-2 h-1) in seawater revealed that CPC was a promising candidate for practical desalination. Outdoor cumulative evaporation was up to 73.2kgm-2 d-1 in weak sunlight and lower temperature, which would meet the daily drinking water demands of 20 people. The excellent cost-effectiveness of 1.085 L h-1 $-1 presented its potential for a wide range of practical applications, such as solar desalination, wastewater treatment, and metal extractions.

Epigenetic analysis in a murine genetic model of Gulf War illness.

Of the nearly 1 million military personnel who participated in the 1990-1991 Gulf War, between 25% and 35% became ill with what now is referred to as Gulf War Illness (GWI) by the Department of Defense. Symptoms varied from gastrointestinal distress to lethargy, memory loss, inability to concentrate, depression, respiratory, and reproductive problems. The symptoms have persisted for 30years in those afflicted but the basis of the illness remains largely unknown. Nerve agents and other chemical exposures in the war zone have been implicated but the long-term effects of these acute exposures have left few if any identifiable signatures. The major aim of this study is to elucidate the possible genomic basis for the persistence of symptoms, especially of the neurological and behavioral effects. To address this, we performed a whole genome epigenetic analysis of the proposed cause of GWI, viz., exposure to organophosphate neurotoxicants combined with high circulating glucocorticoids in two inbred mouse strains, C57BL/6J and DBA/2J. The animals received corticosterone in their drinking water for 7days followed by injection of diisopropylfluorophosphate, a nerve agent surrogate. Six weeks after DFP injection, the animals were euthanized and medial prefrontal cortex harvested for genome-wide DNA methylation analysis using high-throughput sequencing. We observed 67 differentially methylated genes, notably among them, Ttll7, Akr1c14, Slc44a4, and Rusc2, all related to different symptoms of GWI. Our results support proof of principle of genetic differences in the chronic effects of GWI-related exposures and may reveal why the disease has persisted in many of the now aging Gulf War veterans.

Techno-economic scenario analysis of containerized solar energy for use cases at the food/water/health nexus in Rwanda

Techno-economic scenario analysis of containerized solar energy for use cases at the food/water/health nexus in Rwanda

Marine biomass metal-organic framework hybrid evaporators for efficient solar water purification

Marine biomass metal-organic framework hybrid evaporators for efficient solar water purification

Analysis of rainwater storage and use recommendations: From the perspective of DBPs generation and their risks

As a vital freshwater resource, rainwater is usually stored in water cellars in arid regions to solve the daily drinking water problems of the population. However, the status of disinfection by-products (DBPs) generation in cellar water under intermittent disinfection conditions is unclear. Therefore, we investigated the formation and distribution characteristics of DBPs in cellar water under intermittent disinfection conditions for the first time. The results demonstrated that six categories of DBPs were selected for detection after chlorination, including trihalomethanes (THMs), haloacetic acids (HAAs), haloketones (HKs), haloacetonitriles (HANs), halonitromethanes (HNMs), and nitrosamines (NAs), among which HAAs, HKs, and HANs were the major DBPs. Only bromoacetic acid (MBAA), dichloroacetic acid (DCAA), and trichloroacetic acid (TCAA) showed an increasing trend of accumulation as the number of disinfections increased. Meanwhile, the precursor composition was gradually transformed from humic substances to amino acids, and both organic substances were the main precursors of HAAs. The health risk assessment showed that the main carcinogenic and non-carcinogenic risks of cellar water were contributed by NAs and HAAs, respectively, and children are more susceptible to the risks than adults. The best time to drink cellar water is after approximately 12 days of storage, when the total carcinogenic risk is the minimum.

Prenatal and postnatal exposure to polystyrene microplastics induces testis developmental disorder and affects male fertility in mice

Polystyrene microplastics (PS-MPs) can threaten human health, especially male fertility. However, most existing studies have focused on the adulthood stage of male reproduction toxicity caused by relatively short-term PS-MP exposure. This study aimed to investigate the toxic effect of PS-MPs on testicular development and reproductive function upon prenatal and postnatal exposure. Pregnant mice and their offspring were exposed to 0, 0.5mg/L, 5mg/L, and 50mg/L PS-MPs through their daily drinking water from gestational day 1 to postnatal day (PND) 35 or PND70. We found that PS-MP exposure induced testis development disorder by PND35 and spermatogenesis dysfunction by PND70. By combining RNA sequencing results and bioinformatics analysis, the hormone-mediated signaling pathway, G1/S transition of the mitotic cell cycle, coregulation of androgen receptor activity, and Hippo signaling pathway were shown to be involved in testis development on PND35. The meiotic cell cycle, regulation of the immune effector process, neutrophil degranulation, and inflammation mediated by chemokine and cytokine signaling pathways were associated with disturbed spermatogenesis on PND70. These findings show that prenatal and postnatal exposure to PS-MPs resulted in testis development disorder and male subfertility, which may be regulated by the Hippo signaling pathway and involve an immune reaction.

Analysis of Iron (Fe) Level In Alkaline Water in Makale District, Tana Toraja Regency

Alkaline water is drinking water that can be drunk directly because it meets the requirements for drinking water quality. Alkaline water has a pH above 7 so this water is alkaline which can neutralize the acidity in the body. This study aims to determine how much iron (Fe) is dissolved in alkaline water. The initial stage of this research is to obtain data on people who consume alkaline water as their daily drinking water. Furthermore, the sampling used purposive sampling method, based on the sample criteria, namely alkaline water treatment which sourced from well water, rain water and PDAM water. The last step is to analyze the levels of iron (Fe) with laboratory tests at the Center for Environmental Health Engineering and Disease Control Class 1 Makassar. The time of the study began in July 2022. The sample of this study was taken as many as 3 samples. This research method uses an Inductively Couple Plasma spectrometer to determine the level of iron (Fe) in alkaline water. Based on the laboratory tests that have been carried out, the results of the three samples did not exceed the normal limit set by the Minister of Health, namely 0.3 mg/L.

Efficacy of chlorogenic acid against ethylene glycol-induced renal stone model: The role of NFKB-RUNX2-AP1-OSTERIX signaling pathway

Renal tissue injuries by free radicals are an essential reason in pathogenesis of urinary tract stones. Ethylene glycol is one of the toxic agents which can causes to the increases in biosynthesis of reactive oxygen species and oxidative stress condition. Natural antioxidants have been reported to protective efficacy against renal stones formation. Accordingly, the aim of the current experiment was to identify the renal protective effect of chlorogenic acid as a well-prominent antioxidant on ethylene glycol-induced renal stone model targeting the NFKB-RUNX2-AP1-OSTERIX signaling pathway. Renal stones model were established by ethylene glycol (Percent: 0.75) within the daily drinking water for rats. Treatment groups received cystone (750mg/kg) and chlorogenic acid (100, 200, and 400mg/kg, day: 15th to 28th, gavage). After 4 weeks, the renal function parameters (calcium, uric acid, creatinine, total protein, oxalate, and citrate) in plasma, urine, and renal tissue were measured. Moreover, oxidative stress factors and gene expression of NFKB, RUNX2, AP1, and OSTERIX were also evaluated. The results showed improved renal function in chlorogenic acid-treated groups. The total proteins and creatinine excretion were decreased. Also the gene expression of oxidative stress pathway (NFKB-RUNX2-AP1-OSTERIX) were decreased which caused to increases of antioxidant enzymes. the antioxidant activity increases by chlorogenic acid treatment may have a critical role in prevention of calcium oxalate formation via inhibition of the NFKB-RUNX2-AP1-OSTERIX signaling pathway.

Plant transpiration-inspired environmental energy-enhanced solar evaporator fabricated by polypyrrole decorated polyester fiber bundles for efficient water purification

Solar steam production is regarded as a potential approach for extracting freshwater from undrinkable water. However, it remains a challenge to acquire a low-cost, salt-resistant, durable and efficient solar evaporator through a simple fabrication process. This work presents a plant transpiration-inspired three-dimensional (3D) solar evaporator fabricated by decorating industrial polyester fiber bundles (PFBs) with inexpensive polypyrrole (PPy). This solar evaporator is named the PPy-PFBs. Intriguingly, PFBs composed of hydrophobic polyester fibers with multiple vertical channels are capable of pumping enough water to the top of the solar evaporator through the capillary effect and storing seven times its mass of water, allowing for salt-resistant. In addition, polyester fiber is resistant to acid, alkali, mildew, and sunlight, making the PPy-PFBs durable. Along with the heat generated from sunlight absorbed by the PPy, the 3D solar evaporator can also gain energy from the environment. Adjusting the exposure height and arrangement of PPy-PFBs can control the evaporation rate. The matrix arranged PPy-PFBs with an exposure height of 6 cm attains a high water evaporation rate of 3.77 kg m −2 h −1 with an energy conversion efficiency of 155.77%. Outdoor experiments demonstrate that the PPy-PFBs can extract freshwater from non-drinkable water. 1 m 2 of PPy-PFBs can produce about 26 kg of fresh water per day, which is enough to meet the daily drinking water needs of 10 adults. This low-cost, easily made, salt-resistant, durable and high evaporation rate solar evaporator is appealing to alleviate the global freshwater crisis. • Solar evaporators derived from hydrophobic ingredients with vertical channels are hydrophilic. • The evaporation rates can be controlled by adjusting the exposure height and arrangement of the 3D solar evaporators. • The matrix arranged PPy-PFBs with the exposure height of 6 cm achieves a high water evaporation rate of 3.77 kg m −2 h −1 . • PPy-PFBs shows salt-resistant. • Seawater and industrial wastewater can be purified by PPy-PFBs evaporators.

Health Risk Analysis of Detergent Contamination in Communities on Kodingareng Lompo Island, Makassar City

Domestic activities in coastal and island communities are one of the factors that can affect the quality and quantity of traditional well water availability. One of the parameters of household wastewater is detergent pollutants. This study aimed to analyze the risk of detergent contamination in drinking water in the community of Kodingareng Lompo Island. This research is a type of quantitative research with a descriptive approach. The method used is the Environmental Health Risk Assessment (EHRA) approach. Based on the examination conducted, the highest concentration was found in drinking water samples 4 and 5, which was equal to 2.98 mg/l. While drinking water sample 2 has the lowest concentration of detergent contamination, which is 0.005 mg/l. The respondents' daily drinking water intake rate is < 2 L/day, 2 L/day and ≥ 2 L/day, with the highest percentage of 31.1% for consumption of 2 L/day. The frequency of detergent exposure in drinking water consumed by respondents, namely > 350 days/year, with a percentage of 84.4%. The most extended duration of exposure, namely 31 - 60 years, with a ratio of 64.4%. The results of ARKL calculations conducted on the concentration of detergent contamination in drinking water showed a high level of risk (RQ > 1) in three respondents and were classified as unsafe for drinking water consumption.

Cuttlebone‐Derived Interfacial Solar Evaporators for Long‐Term Desalination and Water Harvesting

AbstractInterfacial solar‐vapor generation is very promising for obtaining freshwater, but suffers from serious evaporation rate degradation due to salt‐fouling and low freshwater collection rate under natural sunlight. Here, cuttlebone‐derived solar evaporators for long‐term desalination and water harvesting are reported. The solar evaporators are prepared by modifying the cuttlebone in turn with polydopamine, reduced graphene oxide, and polypyrrole as the photothermal composite. The solar evaporator shows i) excellent photothermal effect owing to a synergistic effect between the photothermal composite and its hierarchical micro‐/nanostructure, and ii) stable evaporation rate and good salt resistance even during the evaporation of concentrated brines (3.5–20 wt%) because of ultrafast water transport in the superhydrophilic 3D directional channels. The ultrafast water transport guarantees sufficient water supply, automatic very fast salt exchange, and a decline in salt concentration gradient. The transverse and longitudinal water streaming allows the increased salt concentration or even the temporarily deposited salt in/on the evaporator to be transferred back to the bulk brine in time. Consequently, 8.32 kg m−2 of freshwater is collected in 10 h solar desalination under weak natural sunlight, which is adequate for the daily drinking water demand of several people.