Nanotechnology has an increasingly large impact on a broad scope of biotechnological, pharmacological and pure technological applications. Its current use in bioenergy production from biomass is very ...restricted. The present study is based on the utilization of nanoparticles as an additive to feed bacteria that break down natural substances. The novel notion of dosing ions using modified nanoparticles can be used to progress up biogas production in oxygen free digestion processes. While minute nanoparticles are unstable, they can be designed to provide ions in a controlled approach, so that the maximum enhancement of biogas production that has been reported can be obtained. Nanoparticles are dissolved in a programmed way in an anaerobic atmosphere and are supplied in a sustainable manner to microbiotic organisms responsible for the degradation of organic material, which is a role that fits them well. Therefore, biogas fabrication can be increased up to 200%, thereby increasing the degradation of organic waste.
Concentrations of biogenic silica (BSi) in the southern Yellow Sea were determined during four cruises (spring: April-May 2014; autumn: November 2014; summer: August-September 2015; winter: January ...2016). Samples of BSi were measured using the double extraction method. Seasonal and spatial variations of BSi and the potential correlation between chlorophyll
a
(Chi
a
) content and BSi in four seasons were measured in this study. Significant spatial variability was observed in seawater BSi concentrations. The average concentration of BSi was highest in winter and lowest in spring. Furthermore, the relationships between concentrations of BSi and hydrological parameters were also discussed. There was a significant positive correlation between Chi
a
and BSi. The concentrations of BSi showed significant relationships with temperature and the concentrations of silicates, total inorganic nitrogen and total inorganic phosphorus, indicating that distribution of BSi was affected by temperature and nutrient level.
Anaerobic digestion (AD) is one of the most popular renewable energy technologies. The AD process produces sustainable energy using various low-cost wastes. Although AD technology is widely used, its ...low biodegradation efficiency and poor stability limit its commercial application. The use of additives has been shown to offer marked improvements in AD performance. However, in practice, the use of additives in AD is not fully understood. In this review, the principles and achievements of additives (including metal elements, carbon-based accelerants, biological additives, and alkali addition) promoting AD performance are summarized. The review also discusses the issues and development trend of each additive. There are still many challenges associated with using additives in AD systems owing to significant variations in digestion substrates and AD operational procedures. The dosage and types of additives have a great influence on the efficiency of AD, which mainly depend on the substrate. Moreover, the implementation process of each additive is not perfect. Therefore, it is essential to better utilize additives to promote AD performance according to the merits of each material. The application of composite additives requires further exploration to optimize the implementation process. This paper deepens our understanding of flexible additives in the AD process and provides comprehensive information that can be used to promote renewable clean energy.
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•Additive provides a valuable method to increase biogas production.•The type and dosage of additives have a great influence on the efficiency of AD.•The selection of additives for AD system depends on the substrate of AD system.•The combination of different additives is a future trend.
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•A mixed-mode chromatography method was applied to the quality control of PAMA injection.•The main components Asp, K+, Mg2+ and the impurity Na+ were evaluated simultaneously.•Several ...single factor experiments analysis were used to optimize the chromatography conditions.
This study describes an analytical method to control the quality of potassium aspartate and magnesium aspartate (PAMA) injection based on the simultaneous detection of the main components (K+, Mg2+ and Asp) and impurities (Na+) using a mixed-mode chromatography coupled with charged aerosol detector. To obtain optimal chromatographic separation, the effects of organic content, column temperature, buffer types, pH and concentrations were evaluated. A Response Surface Methodology (RSM) optimal design was performed after single factor experiment. The mixed-mode HPLC method is proved to be a complementary approach to the conventional ion chromatography (IC). The optimized method was successfully validated and applied to the analysis of Asp, K+, Na+ and Mg2+ in PAMA injection with good specificity, linearity, accuracy, and repeatability. The method would be useful for quality control in PAMA injection and other similar drugs, which can provide references for the analysis of drug quality by enterprises and drug regulatory department.
The ecological province based on phytoplankton species composition is important to understanding the interplay between environmental parameters and phytoplankton species composition. The aim of this ...study was to establish phytoplankton species composition ecological pattern thus elucidate the relationship between environmental factors and the phytoplankton species composition in the ecological provinces. Phytoplankton samples were collected from 31 stations in Yellow Sea (121.00°-125.00°E,32.00°-39.22°N) in November 2014. The samples were enumerated and identified with the Uterm?hl method under an optical inverted microscope-AE2000 with magnifications of 200 × or 400 ×. In the present study, a total of 141 taxa belonging to 60 genera of 4 phyla of phytoplankton were identified, among them 101 species of 45 genera were Bacillariophyta, 36 species of 11 genera were Dinophyta, 3 species of 3 genera were Chrysophyta and 1 species of 1 genera was Chlorophyta. The study area was divided into 4 ecological provinces according to an unsupervised cluster algorithm applied to the phytoplankton biomass. A T-S (Temperature- Salinity) scatter diagram depicted with data of water temperature and salinity defined by environmental provinces matched well with the ecological provinces. The results of Canonical Correspondence Analysis (CCA) indicated that the phytoplankton species composition was mainly correlated with temperature, salinity and silicate concentration in the studied area. A method of establishing ecological provinces is useful to further understanding the environmental effects on the marine phytoplankton species composition and the consequent marine biogeochemistry.
Phytoplanktonic ecological provinces of the Yellow Sea（31.20°–39.23°N, 121.00°–125.16°E） is derived in terms of species composition and hydrological factors（temperature and salinity）. 173 samples ...were collected from 40 stations from April 28 to May 18, 2014, and a total of 185 phytoplanktonic algal species belonging to 81 genera of 7phyla were identified by Uterm？hl method. Phytoplankton abundance in surface waters is concentrated in the west coast of Korean Peninsula and Korea Bay, and communities in those areas are mainly composed of diatoms and cyanobacteria with dominant species of Cylindrotheca closterium, Synechocystis pevalekii, Chroomonas acuta,Paralia sulcata, Thalassiosira pacifica and Karenia mikimotoi, etc. The first ten dominant species of the investigation area are analyzed by multidimensional scaling（MDS） and cluster analysis, then the Yellow Sea is divided into five provinces from Province I（P-I） to Province V（P-V）. P-I includes the coastal areas near southern Liaodong Peninsula, with phytoplankton abundance of 35 420×10^3–36 163×10^3 cells/L and an average of 35 791×10~3 cells/L, and 99.84% of biomass is contributed by cyanobacteria. P-II is from Shandong Peninsula to Subei coastal area. Phytoplankton abundance is in a range of 2×10^3–48×10^3 cells/L with an average of 24×10^3cells/L, and 63.69% of biomass is contributed by diatoms. P-III represents the Changjiang（Yangtze River） Diluted Water. Phytoplankton abundance is 10×10^3–37×10^3 cells/L with an average of 24×10^3 cells/L, and 73.14% of biomass is contributed by diatoms. P-IV represents the area affected by the Yellow Sea Warm Current.Phytoplankton abundance ranges from 6×10^3 to 82×10^3 cells/L with an average of 28×10^3 cells/L, and 64.17% of biomass is contributed by diatoms. P-V represents the cold water mass of northern Yellow Sea. Phytoplankton abundance is in a range of 41×10^3–8 912×10^3 cells/L with an average of 1 763×10^3 cells/L, and 89.96% of biomass is contributed by diatoms. Overall, structures of phytoplankton community in spring are quite heterogeneous in different provinces. Canonical correspondence analysis（CCA） result illustrates the relationship between dominant species and environmental factors, and demonstrates that the main environmental factors that affect phytoplankton distribution are nitrate, temperature and salinity.
Diatoms are the only ecological phytoplankton that require silicic acid for growth. They are also the dominant contributor of ocean’s total primary productivity. Generation and circulation with ...silica walls, which the siliceous organisms form, is an important component of the marine biological pump. It is crucial to the study of the operational mechanisms of biological pump with different sea areas. Moreover, it is the key link to the study of global silicon cycle. This paper introduces the basic mechanism of the formation of diatom silica walls and a new way of researching silicic acid metabolism, namely the 2-(4-pyridyl)-5-((4-(2-dimethylaminoethylaminocarbamoyl)-methoxy)phenyl)oxazole (PDMPO) dyeing method. Under a fluorescence microscope after excitation with bright green fluorescence, it can combine with silicic acid to form a complex into the Si deposition within diatom cells. The advantage of this method is that it can monitor the metabolism of silicate after adding PDMPO. For experimentation and sample collection in each of the specified time points, samples were determinated through the unutilized silicic acid, silica dissoluble intracellular and Si deposition within diatom cells, not only using hot alkaline digestions method but also PDMPO dyeing method. Results showed a good linear relationship between PDMPO fluorescent value and biogenic silica concentration. It was also indicated that PDMPO had no deleterious impact on Skeletonema cf. costatum growth for 34 h and was useful for tracking newly-deposited biogenic silica in diatoms’ frustules.
Diatoms are the only ecological phytoplankton that require silicic acid for growth.They are also the dominant contributor of ocean’s total primary productivity.Generation and circulation with silica ...walls,which the siliceous organisms form,is an important component of the marine biological pump.It is crucial to the study of the operational mechanisms of biological pump with different sea areas.Moreover,it is the key link to the study of global silicon cycle.This paper introduces the basic mechanism of the formation of diatom silica walls and a new way of researching silicic acid metabolism,namely the 2-(4-pyridyl)-5-((4-(2-dimethylaminoethylaminocarbamoyl)-methoxy)phenyl)oxazole(PDMPO) dyeing method.Under a fluorescence microscope after excitation with bright green fluorescence,it can combine with silicic acid to form a complex into the Si deposition within diatom cells.The advantage of this method is that it can monitor the metabolism of silicate after adding PDMPO.For experimentation and sample collection in each of the specified time points,samples were determinated through the unutilized silicic acid,silica dissoluble intracellular and Si deposition within diatom cells,not only using hot alkaline digestions method but also PDMPO dyeing method.Results showed a good linear relationship between PDMPO fluorescent value and biogenic silica concentration.It was also indicated that PDMPO had no deleterious impact on Skeletonema cf.costatum growth for 34 h and was useful for tracking newly-deposited biogenic silica in diatoms’ frustules.
Seasonal nutrient dynamics regulated by hydrological and biological variables in the southern Yellow Sea (SYS) were studied based on the datasets collected during four cruises: spring (April 28-May ...10, 2014), summer (August 17-September 22, 2015), autumn (November 7–17, 2014) and winter (January 13-February 1, 2016). In the present study, by dividing the study area into three distinct current-dominated subregions based on T-S distribution, cluster analysis, and principal components analysis (PCA), we revealed that the response mechanisms of nutrients to physical and biological processes were important. Among all factors, the physical processes, mainly including the Yellow Sea Cold Water Mass (YSCWM) onset, the Changjiang (Yangtze) Diluted water (CDW) and Taiwan Warm Current (TWC) intrusion and the Yellow Sea Warm Current (YSWC) invasion, were the principal driving force, which significantly changed the inherent balance of nutrient structure. Meanwhile, biological depletion was also a significant factor, especially in the stratified seasons, even though its impact on the nutrient structure could be balanced by vigorous water exchange or vertical mixing. The regional variation of nutrient regime and the regulatory mechanism behind it were revealed at the same time. The coastal area showed strong signs of potential P limitation as a result of excessive dissolved inorganic nitrogen (DIN) entering via terrestrial runoff and anthropogenic activities. The 32 °N transect, which is adjacent to the boundary of the SYS and the East China Sea (ECS), showed varying hydrological features due to the strong intrusion of CDW and TWC. Therefore, P or Si were the main limiting factor for the development of algal biomass. The central study area possessed a comparatively stable water column with the specific existence of the YSCWM present at the bottom, thus acting as a potential nutrient pool. Hence, we hypothesized that the offshore side of the study area tended to be more P and N co-limited, whereas the nutrient cycles in the nearshore side showed significant seasonal and regional variations, which corresponded to the change in physical oceanographic processes and algal biomass.
•The study area was divided into three current-driven subregions based on multivariate statistical methods.•The nutrient regime and the regulatory mechanism behind it were revealed between seasons and subregions.•Among all factors, physical processes were defining in controlling nutrient dynamic in the study area.•The central SYS and 32°N transect acted as a potential nutrient pool saving comparable nutrients at the bottom depth.•Different mechanisms caused potential P or Si limitation of coast and P and N co-limitation off shore respectively.
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