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Hydrophobic and breathable nanofiber membranes have attracted considerable attention owing to their applications in various fields. In this study, we fabricated superhydrophobic and breathable nanofiber membranes using solution blow spinning. We optimized the spinning process parameters by analyzing their effects on the structure and properties of the nanofiber membranes. And the nanofiber membranes achieved superhydrophobicity through hydrophobic modification treatment. The average fiber diameter and pore size of the obtained membrane were 0.51 and 13.65 μm, respectively. The membranes exhibited superhydrophobicity, breathability, and mechanical properties: water vapor transmission of 12.88 kg/m

Constructed wetland (CW) is an effective ecological technology to treat water pollution and has the significant advantages of high impact resistance, simple construction process, and low maintenance cost. However, under extreme conditions such as low temperature, high salt concentration, and multiple types of pollutants, some bottlenecks exist, including the difficulty in improving operating efficiency and the low pollutant removal rate. Microbial electrochemical technology is an emerging clean energy technology and has the similar structure and pollutant removal mechanism to CW. Microbial electrochemistry combined with CW can improve the overall removal effect of pollutants in wetlands. This review summarizes characterization methods of microbial electrochemistry-enhanced constructed wetland systems, construction methods of different composite systems, mechanisms of single and composite systems, and removal effects of composite systems on different pollutants in water bodies. Based on the shortcomings of existing studies, the potential breakthroughs in microbial electrochemistry-enhanced constructed wetlands are proposed for developing the optimization solution of constructed wetlands.

Wood pulp-based wetlaid/spunlace (wetlace) materials have become increasingly popular in the field of disposable personal hygiene moist wipes. To achieve excellent products, materials with different short-cut fibers and proportions were fabricated, and the effects of moisture contents on the wet strength and handle properties of the materials were firstly investigated. The results suggest that the wet strength of material composed of regenerated cellulose fibers decreases to about 20% of dry strength, while that made of hydrophilic polyester is only about 8–9% with moisture content of 800%. The softness and smoothness of material consisting of 20% short-cut regenerated cellulose fibers decrease to stable figures at 300% moisture content. The softness parameter was 4.5–5.2, and the smoothness value was 14.5–19, but the stiffness parameter increases to a stable level at 2.6–2.9 mm N−1. Overall, with moisture content of 300%, materials with 20% short-cut fibers achieve the limit of wet strength during use, material made of lyocell has the best wet strength and smoothness, and material made of Viloft possesses the greatest softness and the lowest stiffness.

Solution blowing (SB) is a widely reported technology that can be used to fabricate fibers at the micro- and nanoscale. To reveal the fibrous web formation mechanism in SB, we improved our previous melt blowing (MB) model to predict fibrous web structures. Then, we fabricated two samples and simulated the same number of virtual samples in the computer to verify the model. Thereafter, we measured the structural parameters including the fiber diameter, fiber orientation, basis weight, and pore size. Our model provides a good prediction of the fiber orientation and basis weight. However, the predicted fiber diameter was slightly smaller than the measured diameter. The experimental pore size distribution was also different from that in the simulated results. The model provides a virtual fabrication process to reveal a fibrous web formation mechanism and finds a similar distribution of these structural parameters between SB and MB.

The demand for air filtration materials in recent years has been substantially increasing on a worldwide scale because people are paying extensive attention to particulate matter (PM) pollution. In this work, we report a type of needle-punched triboelectric air filter (N-TAF) consisting of polytetrafluoroethylene (PTFE) fibers modified by silica nanoparticles and polyphenylene sulfide (PPS) fibers. Compared to conventional electrostatic precipitators, the N-TAF can be charged online by a unique nonwoven processing technology without additional energy consumption and toxic ozone emission. Owing to the triboelectrification effect, a large number of charges were generated during the process of carding and needle-punching, resulting in an increased filtration performance. Benefiting from the addition of silica nanoparticles, the PTFE fibers are endowed with many pores and grooves and substantial surface roughness, which contributes to the enhancement of triboelectrification. As a result, the N-TAF with 2 wt % silica nanoparticles (N-TAF-2) exhibited a high removal efficiency of 89.4% for PM, which is 45% higher than unmodified N-TAF (61.8%), and a low pressure drop of 18.6 Pa. Meanwhile, the decay of the removal efficiency for N-TAF-2 remained at a low level (6.4%) for 60 days. More importantly, N-TAF-2 could realize a high efficiency of 99.7% and a low pressure drop of 55.4 Pa at a high surface density. In addition, the washed N-TAF has an excellent charge regeneration performance via air blowing or manual rubbing, thus recovering the removal efficiency easily and rapidly. Ultimately, the powerful dust holding capacity (227 g m

Three-dimensional (3D) woven spacer composites are competitive materials in aerospace fields due to their excellent integrated, light-weight structure. The face sheets of the 3D woven spacer composites are crucial for the mechanical properties. In this study, 3D hybrid composites, which are composed of glass and carbon fibers in the face sheets and glass fiber in the core layer as reinforcement and epoxy resin as the matrix, were designed and fabricated. The bending test results show that with the increase of the carbon fibers in the face sheets, the normalized bending strength of hybrid spacer composites showed limited improvement, while their normalized bending moduli and bending stiffnesses were significantly improved. The optical and scanning electron microscope images of the fractured surfaces reveal that the fibers in the top face sheet, which is under compression by the indenter, are damaged first and cause the failure of the entire structure, whereas the fibers in the bottom face sheets are stretched during the bending test and slightly damaged. In addition, in the failure cross-sections, pull-out of the carbon fibers is observed due to its limited interfacial bonding with the epoxy resin. This work could help optimize 3D hybrid woven spacer composite structures for better performance and lower cost.

Wetlaid/spunlace (wetlace) materials consisting of wood pulp and short-cut fibers are leading the way in the development of dispersible moist wipes due to their wet strength during use and disintegration under flow field. However, short-cut fibers are still not well understood in terms of reasonable balance between material wet strength and dispersibility. In this study, wetlace materials were prepared via four types of water-jet pressure sums, and the effects of four types of short-cut fibers (Lyocell, Danufil, Viloft and hydrophilic polyester) on the wet strength and dispersibility of wetlace materials were investigated for the first time. The results suggest that at a water-jet pressure sum of around 190 bars, wood pulp/Lyocell wetlace material reaches the dispersion threshold, but wood pulp/hydrophilic polyester material has lost dispersibility, and the former wet strength is much higher than the latter. However, the required water-jet pressure sum at the dispersion threshold of wood pulp/Danufil or wood pulp/Viloft wetlace materials are more than 200 bars, and the corresponding wet strength is close to that of wood pulp/Lyocell wetlace material. Overall, Lyocell entanglements as reinforcement of wetlace material can achieve sufficient wet strength and excellent dispersibilty with low water-jet pressure sum, providing guidelines for the production of excellent pulp-based moist wipes.

Lacking of electron donor generally causes the low denitrification performance of constructed wetlands (CWs). Montmorillonite supported nanoscale zero-valent iron immobilized in sodium alginate (SA/Mt-NZVI) as novel electron donor-acceptor compounds were added in the denitrification zone of vertical flow constructed wetlands (VFCWs) to enhance the nitrogen removal. The key factors of the SA/Mt-NZVI dosage, the hydraulic retention time (HRT) of VFCWs, and the C/N ratios of influent were explored. SA/Mt-NZVI significantly improved the nitrogen (NO3--N) removal efficiency in VFCWs. When the optimal dosage of SA/Mt-NZVI was set as 2 g and the C/N was set as 6, the highest NO3--N removal efficiency was improved by 32.5 ± 1.0%. The microbial community analysis of by 16S rRNA had revealed that Proteobacteria and Bacteroidetes at phylum level and Betaproteobacteria, Gammaproteobacteria, and Alphaproteobacteria at class level played an important role in nitrogen removal.

Wastewater recycling can alleviate the shortage of water resources. Saline water is seldom treated with biological processes and the recycling utilization is low. Constructed wetland (CW) is a safe and economical ecological water treatment. However, the saline water treatment performance of CW is not good. Microbial desalination cell (MDC) utilizing the bioelectro-chemical principle achieves the functions of desalination and power generation. In this study, MDC was used to strengthen CW to form a composite system, MDC-CW, through optimizing design parameters. MDC-CW was applied in the treatment of salt-containing water. The average total nitrogen removal rate in MDC-CW-P1 reached 87.33% and the average COD removal rate was 92.79%. The average desalination rate of MDC-CW-P1 was 55.78% and the average voltage of MDC-CW-P1 reached 0.40 mV. It was found that planting canna indica in the MDC-CW was conducive to the functions of desalination and power generation. The above results were also verified by the microbial testing results of gravels in substrate, plant rhizosphere and electrodes. In addition, the decontamination of the device mainly depended on the functions of the bacteria commonly used in water treatment, such as Proteobacteria and Bacteroidetes, whereas the generation of power depended on the function of Geobacter. Salt ions moved spontaneously to the cathode and anode under the premise of current generation, so that the desalination function was realized under the selective isolation function of exchange membranes. The device design and laboratory application of MDC-CW experimentally accomplished the electrochemical technology and enlarged the treatment scale of CW.

An aircathode microbial desalination cell (AMDC) was successfully started by inoculating anaerobic sludge into the anode of a microbial desalination cell and then used to study the effects of salinity on performance of AMDC and effect of treatment of coastal saline-alkaline soil-washing water. The results showed that the desalination cycle and rate gradually shorten, but salt removal gradually increased when the salinity was decreased, and the highest salt removal was 98.00 &plusmn, 0.12% at a salinity of 5 g/L. COD removal efficiency was increased with the extension of operation cycle and largest removal efficiency difference was not significant, but the average coulomb efficiency had significant differences under the condition of each salinity. This indicates that salinity conditions have significant influence on salt removal and coulomb efficiency under the combined action of osmotic pressure, electric field action, running time and microbial activity, etc. On the contrary, COD removal effect has no significant differences under the condition of inoculation of the same substrate in the anode chamber. The salt removal reached 99.13 &plusmn, 2.1% when the AMDC experiment ended under the condition of washing water of coastal saline-alkaline soil was inserted in the desalination chamber. Under the action of osmotic pressure, ion migration, nitrification and denitrification, NH4+-N and NO3&minus, N in the washing water of the desalination chamber were removed, and this indicates that the microbial desalination cell can be used to treatment the washing water of coastal saline-alkaline soil. The microbial community and function of the anode electrode biofilm and desalination chamber were analyzed through high-throughput sequencing, and the power generation characteristics, organics degradation and migration and transformation pathways of nitrogen of the aircathode microbial desalination cell were further explained.

Lung adenocarcinoma (LUAD) is the most commonly diagnosed type of lung cancer and exhibits a high morbidity. The present study aimed to investigate the long non-coding RNA (lncRNA)-associated competing endogenous RNA (ceRNA) mechanisms in LUAD. The receptor activity modifying protein 2-antisense RNA 1 (RAMP2-AS1) was identified using GSE113852 and GSE130779 datasets downloaded from the Gene Expression Omnibus database, and the downregulation of RAMP2-AS1 was the most significant in LUAD. In addition, microRNA (miR)-296-5p was identified to bind to RAMP2-AS1 via bioinformatics analysis. Subsequently, CD44, cyclin D3 (CCND3), neurocalcin δ (NCALD), microtubule actin crosslinking factor 1 (MACF1) and potassium channel tetramerization domain containing 15 were obtained by intersecting the predicted target genes of miR-296-5p and 368 differentially expressed mRNAs in LUAD. According to the Gene Expression Profiling Interactive Analysis and UALCAN databases, these five mRNAs were downregulated in LUAD, and their expression levels were positively correlated with those of RAMP2-AS1. CD44, CCND3, NCALD and MACF1 were selected as key mRNAs in LUAD based on prognostic analyses. Furthermore, functional enrichment analyses were performed and an interaction network was constructed to reveal the functions of the RAMP2-AS1-associated ceRNA in LUAD. The results indicated that the functions were mainly enriched in generic transcription pathways, cyclin D-associated events in G1 and epithelial stromal transformation. Reverse transcription-quantitative PCR assays revealed that RAMP2-AS1, CD44, CCND3, NCALD and MACF1 expression was lower in tumor tissues than in normal tissues, while miR-296-5p expression was higher in tumor tissues compared with in normal tissues. The association between RAMP2-AS1 and MACF1 was further confirmed using in vitro experiments. Overall, the present results indicated that RAMP2-AS1, miR-296-5p, CD44, CCND3, NCALD and MACF1 may be involved in LUAD progression and may therefore serve as potential biomarkers and provide a theoretical basis for the study of the pathogenesis of LUAD.

In this study, a three-chamber air–cathode microbial desalination cell (AMDC) was constructed using activated sludge as the inoculating microbial source and carbon cloth as the electrode. The simultaneous bioelectricity generation, desalination, degradation of organic compounds, and nitrogen removal in the AMDC having different electrode spacings (16, 12, and 8 cm) provided an insight into the microbial community. The experimental results showed that with a gradual decrease in the electrode spacing, electricity production and desalination performance first increased and then decreased. While AMDC1 with 16 cm electrode spacing became active faster than other cells and reached a peak voltage of 598 mV on the tenth day, AMDC2 with 12 cm electrode spacing showed the best start-up performance with a maximum output voltage of 645 mV, maximum power density of 214.7 mW/m3, and minimum resistance of 516.9 Ω. AMDC3 with 8 cm electrode spacing reached a peak voltage of 598 mV, which was between those of AMDC1 and AMDC2. The three AMDCs were run until the end of the cycle, and there was no significant difference in their ammonium removal rate and chemical oxygen demand. For AMDC1–3, the desalination rates were 84.86%, 87.71%, and 83.43%, and the Coulomb efficiencies were 17.29%, 18.60%, and 17.95%, respectively. Further, scanning electron microscopy showed that a large number of microorganisms could attach to the surface of the anode carbon cloth electrode; 16S rRNA sequencing showed that the typical electrogenic microbial communities were Bacillus (11.6%) and Arcobacter (9.6%). As the poor performance of the AMDC was primarily due to a lack of electrogenic microorganisms in the active function of the anode chamber, screening the functional microorganisms provided a reference for optimizing and amplifying the application of microbial desalination cells in practical research.

Wood pulp/Danufil nonwovens have been prepared by wetlaid/spunlace method as a potential and new dispersible moist wipes. To verify the potential applications of the wetlaid/spunlace nonwovens, this study investigated the wet strength, softness/smoothness, and dispersibility of wetlaid/spunlace nonwovens with different Danufil contents and length-to-diameter ratios. Meanwhile, these properties were compared with three other types of commonly-used dispersible moist wipes. The results show that an increase in Danufil content or length-to-diameter ratio results in increasing wet strength and decreasing dispersibility of wetlaid/spunlace nonwovens. However, an increase in pulp content or Danufil length-to-diameter ratio will increase real softness and weaken felt smoothness of materials. In addition, the average machine and cross directions wet strength are 9.5 N/50 mm and 6.3 N/50 mm, respectively. The real softness and corresponding felt smoothness of wetlaid/spunlace nonwovens range from 10.8 to 16.3 and from 37.1 to 22.0, respectively. The average required dispersion time of wetlaid/spunlace nonwovens are controlled within 21 min. Overall, the wood pulp/Danufil wetlaid/spunlace nonwovens have the similar wet strength but excellent softness/smoothness and dispersibility when compared with the currently used dispersible products, and possess high feasibility and potential for dispersible moist wipes industry.

Wetlaid/spunlace(wetlace) nonwovens with sufficient wet strength in use and disintegration under flow field can be widely used in dispersible moist wipes. To achieve superior properties, wood pulp/Lyocell wetlace nonwovens at different process parameters including pressure sum (sum of each Jet Head pressure), Lyocell blend ratio, and basis weight were prepared. Meanwhile, the effects of these process parameters on the wet strength and dispersibility of materials were investigated. The results show that the wet strength of wood pulp/Lyocell wetlace nonwoven increases as the increase of process parameters. Pressure sum has positive linear relationship with material wet strength and exponential relationship with material dispersibility. When pressure sum is beyond 135 bars, material basis weight has significant influence on the dispersibility. Pressure sum of 210 bars is the key value that Lyocell content affects the material dispersibility. Overall, at the minimum pressure sum of 190 bars, wood pulp/Lyocell (60/40) wetlace nonwoven (80 g m−2) has dispersion critical value with maximum wet strength.

There are various test methods applied to measure mean linear density of PTFE split-film fibers. The measured results vary with respect to computation mechanisms, measurement parameters, and morphology and inherent properties of fibers. Five test methods and an assumption calculation were introduced to evaluate the linear densities of PTFE fibers. The experimental results show that the gravimetric method generated the highest linear density, followed by the cross-section method, theory calculation, airflow measurement, assumption calculation, and vibration method. Statistical analyses indicated that actual mean linear density of the PTFE split-film fibers is in the effective range between the maximum and minimum fineness obtained from the theory and assumption calculation, respectively. Linear density of the PTFE split-film fiber tested via the gravimetric method, cross-section method, and vibration operation were significantly different to the effective range. In the case of the airflow experiment, mean linear densities measured at high porosities are in high accordance with the actual fineness. The airflow method offers a short time to reliably measure mean linear density of PTFE split-film fibers under appropriate test conditions.

A new wiping product prepared by wetlaid/spunlace (wetlace) method possess dispersibility and fully degradability. To obtain the excellent products, the present research first investigates the apparent microstructures, mechanical properties and dispersibility of wood pulp/Danufil wetlaid nonwovens with/without hydroentanglement. The results suggest that fibers are stacked and some of the fiber cohesions occurred on the surface of wetlaid nonwoven. After hydroentanglement, a 3D entanglement skeleton formed by Danufil fibers is found to determine the mechanical and dispersion properties of nonwovens, while wood pulp ensures the dispersion properties and is attributed as the main component of the nonwovens. The breaking extension and tearing strength of nonwovens have been improved significantly and the material with decreasing dispersibility becomes soft. Meanwhile, the dispersion of wetlaid and wetlace nonwovens over time both show linear fitting trend. The increase in content and length-to-diamete...

The effects of various combinations of iron compounds on the contaminant removal performance in constructed wetlands (CWs) were explored under various initial iron concentrations, contaminant concentrations, different hydraulic retention time (HRT), and different temperatures. The Combo 6 (nanoscale zero-valent iron combined with Fe3+) in CW treatments showed the highest pollutant removal performance under the conditions of C2 initial iron dosage concentration (total iron 0.2 mM) and I2 initial contaminant concentration (COD:TN:TP = 60 mg/L:60 mg/L:1 mg/L) in influent after 72-h HRT. These results were directly verified by two different microbial tests (Biolog test and high-throughput pyrosequencing) and microbial community analysis (principal component analysis of community-level physiological profile, biodiversity index, cluster tree, relative abundance at order of taxonomy level). Specific bacteria related to significant improvements in contaminant removal were domesticated by various combinations of iron compounds. Iron dosage was advised as a green, new, and effective option for wastewater treatment.

Supplemental Material, supplementary_data for Time-Dependent Toxicities of Quorum Sensing Inhibitors to Aliivibrio fischeri and Bacillus subtilis by Yueheng Zhang, Jinyuan Song, Ting Wang, Haoyu Sun, Zhifen Lin, and Yinjiang Zhang in Dose-Response

Wood pulp-based wetlaid/spunlace (wetlace) materials had an in-use dry or wet strength, but relatively quickly breakdown in municipal sanitization systems without block, such as sewer or septic systems. In order to further study the mechanism and characterization of material dispersion process, the relationship between dispersion time and sample residual rate or dispersion rate was analyzed on the basis of previous research methods. Meanwhile, the crowding factor was introduced for evaluation and the material dispersion mechanism was comprehensively expounded. The dispersion properties of wood pulp-based wetlace materials with different Danufil length-to-diameter (L/D) ratios and contents could be clearly distinguished at the stirring rate of 220 rpm. Meanwhile, the crowding factor was between 14 and 60 when wetlace materials reached dispersion balance, and the increase in crowding factor of wood pulp/Danufil-water dispersion system resulted in increasing the required dispersion time. Overall, the dispersion process could be divided into four stages: stable state of relative dispersion rate (low level), rapid ascent phase, fast descent stage, and constant region again (high level).

Quorum sensing inhibitors (QSIs) are being used widely as a promising alternative to antibiotics and drawing attention as potential pollutants. However, the assessment methods of the toxicities of QSIs, including model organism and affecting time, have not been established. To investigate how model organism and acting time impact the toxicities of QSIs, the effect of 4 QSIs to Aliivibrio fischeri and Bacillus subtilis were determined at different exposing time in the present study. The results showed that the toxic effects of QSIs to gram-negative bacteria (A fischeri) and gram-positive bacteria (B subtilis) were different and time dependent. As for A fischeri, QSI (furaneol acetate, FA) merely showed inhibition on the bioluminescence from hours 1 to 2. But from hours 3 to 6, low concentration FA exerted stimulation on the bioluminescence. Then, this stimulation disappeared from hours 7 to 14, and after hour 15 the stimulation appeared again. That is to say, QSIs showed intermittent hormesis effect on the bioluminescence of A fischeri. By contrast, only inhibition was observed in the toxicity test process of QSIs to B subtilis. As exposing time goes, the inhibition weakened gradually when FA was at low concentration regions. What is more, in the present, study toxic mechanisms were also discussed based on model organisms and exposing time. This study demonstrates appreciable impacts of model organism and exposing time on toxicities of QSIs and provides a theoretical basis for risk assessments after QSIs being widely used into the environment.

In the paper, we explored the influences of different dosages of iron and calcium carbonate on contaminant removal efficiencies and microbial communities in algal ponds combined with constructed wetlands. After 1-year operation of treatment systems, based on the high-throughput pyrosequencing analysis of microbial communities, the optimal operating conditions were obtained as follows: the ACW10 system with Fe 3+ (5.6 mg L −1 ), iron powder (2.8 mg L −1 ), and CaCO 3 powder (0.2 mg L −1 ) in influent as the adjusting agents, initial phosphorus source (PO 4 3− ) in influent, the ratio of nitrogen to phosphorus (N/P) of 30 in influent, and hydraulic retention time (HRT) of 1 day. Total nitrogen (TN) removal efficiency and total phosphorus (TP) removal efficiency were improved significantly. The hydrolysis of CaCO 3 promoted the physicochemical precipitation in contaminant removal. Meanwhile, Fe 3+ and iron powder produced Fe 2+ , which improved contaminant removal. Iron ion improved the diversity, distribution, and metabolic functions of microbial communities in integrated treatment systems. In the treatment ACW10, the dominant phylum in the microbial community was PLANCTOMYCETES , which positively promoted nitrogen removal. After 5 consecutive treatments in ACW10, contaminant removal efficiencies for TN and TP respectively reached 80.6% and 57.3% and total iron concentration in effluent was 0.042 mg L −1 .

Since the reform and opening up in the last century, many cities in China have entered the rapid stage of development, at the same time, the problem of urban water environment pollution has become increasingly prominent. Good water environment is the basic guarantee of the healthy and harmonious development of the city, therefore, people begin to invest a lot of energy on how to control the polluted water of the city reasonably and efficiently. In this paper, the present situation of water environment in most cities of our country is summarized, and the main technical measures and their advantages and disadvantages of urban polluted water treatment in the past are briefly analysed. And it further expounds on how to integrate landscape ecological construction technology into the treatment of urban polluted water in details in order to provide reference for the future urban water environment management.

Quorum sensing inhibitors (QSIs) are being used widely as a promising alternative to antibiotics and drawing attention as potential pollutants. However, the assessment methods of the toxicities of QSIs, including model organism and affecting time, have not been established. To investigate how model organism and acting time impact the toxicities of QSIs, the effect of 4 QSIs to Aliivibrio fischeri and Bacillus subtilis were determined at different exposing time in the present study. The results showed that the toxic effects of QSIs to gram-negative bacteria (A fischeri) and gram-positive bacteria (B subtilis) were different and time dependent. As for A fischeri, QSI (furaneol acetate, FA) merely showed inhibition on the bioluminescence from hours 1 to 2. But from hours 3 to 6, low concentration FA exerted stimulation on the bioluminescence. Then, this stimulation disappeared from hours 7 to 14, and after hour 15 the stimulation appeared again. That is to say, QSIs showed intermittent hormesis effect on the bioluminescence of A fischeri. By contrast, only inhibition was observed in the toxicity test process of QSIs to B subtilis. As exposing time goes, the inhibition weakened gradually when FA was at low concentration regions. What is more, in the present, study toxic mechanisms were also discussed based on model organisms and exposing time. This study demonstrates appreciable impacts of model organism and exposing time on toxicities of QSIs and provides a theoretical basis for risk assessments after QSIs being widely used into the environment.

This paper analyzed the content, distribution, and sedimentation mechanism of Cd in Jiaozhou Bay based on investigation data in April, July and October 1985. Results showed that the Cd contents in surface waters ranged from 0.04-0.32 μg L -1 , and were meeting Grade I for Cd (1.00 μg L -1 ) in Chinese Sea Water Quality Standard, indicated that Jiaozhou Bay and the open sea had not been polluted by Cd in 1985. High Cd sedimentation locations were occurring in different regions due to Cd contents were different in surface waters. In April and October, high Cd sedimentation location was in the open sea in where marine current was the major source; while in July, high Cd sedimentation location was in the bay mouth in where stream flow was the major source. In generally, the spatial-temporal of sedimentation features of Cd were determined by pollution sources and the vertical water's effect.

Based on investigation data on Pb in surface waters in Jiaozhou Bay during 1979 to 1983, this paper analyzed the annual change of both contents and pollution levels of Pb. Results showed that Pb contents in surface waters in Jiaozhou Bay in 1979, 1980, 1981, 1982 and 1983 were 0.25-1.52 μg L -1 , 0.07-2.71 μg L -1 , 0.00-3.34 μg L -1 , 0.30-3.35 μg L -1 and 0.58-2.34 μg L -1 , respectively, indicated that his bay had been slightly of moderated polluted by Pb in 1979 to 1983, and the pollution level of Pb in Jiaozhou Bay was increasing since the reform and opening-up. The promotion of waste treatment and environmental protection was essential. The investigation data of this study would be basic information to the relevant scientific research on this bay.

This paper analyzed the content, distribution, source and background level of PHC in Jiaozhou Bay based on investigation data in April, July and October 1986. Results showed that the PHC contents in surface waters ranged from 0.005-0.122 mg L -1 , and were meeting Grade I/II (0.05 mg L -1 ) and Grade III (0.30 mg L -1 ) in Chinese Sea Water Quality Standard, indicated that the pollution level of PHC in Jiaozhou Bay was slight/moderate in 1986. Stream flow and marine current were the two major PHC sources, whose source strengths were 0.017-0.066 mg L -1 and 0.122 mg L -1 , respectively. The pollution of PHC in the open waters, by contrast, was higher than in

By investigation data in Jiaozhou bay waters from 1979 to 1986(absent of 1980), in spacial scale, by the analysis of the annual dataset, from the view of the content, and the horizontal, vertical and seasonal distributions of HCH, the study of the source, water quality, distribution and transfer state in Jiaozhou bay showed many results of the HCH transfer laws. In temporal scale, by the analysis of the five-year dataset from 1979 to 1986(absent of 1980), the study of the variation process of HCH in Jiaozhou bay showed the below results: the annual variation of the content, the change process of the source, the land transfer process, the water transfer process and the sedimentary process. These laws and process variations provided the solid theoretical base for the HCH transfer in the water body and edified for the study of the other organic compound transfer in the water body.

In this paper, the commonly used method and current used index system for comprehensive evaluation of water quality of ocean dumping areas are analyzed. We found that the normal methods such as single factor method and comprehensive index method are more and more unqualified to deal with the nonlinear, non-normal distribution, and high dimensional of the data, while the indexes should be added because new toxic pollutants brought to dumping areas as the rapid grows of ocean dumping activities is also rapidly increasing. Finally, a system of evaluation indexes and methods for comprehensive evaluation of water quality of ocean dumping areas is constructed.