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2022 ◽  
Vol 14 (2) ◽  
pp. 858
Author(s):  
Jingjie Wang ◽  
Xiaoshuan Zhang ◽  
Xiang Wang ◽  
Hongxing Huang ◽  
Jinyou Hu ◽  
...  

The of monitoring the Internet of Things (IoT) in the cold chain allows process data, including packaging data, to be more easily accessible. Proper optimization modelling is the core driving force towards the green and low-carbon operation of cold chain logistics, laying the necessary foundation for the development of a data-driven modelling system. Since efficient packaging is necessary for loss control in the cold chain, its final efficiency during circulation is important for realizing continuous loss prevention and efficient supply. Thus, it is urgent to determine how to utilize these continuously acquired data and how to formulate a more accurate packaging efficiency control methodology in the agri-products cold chain. Through continuous monitoring, we examined the feasibility of this topic by focusing on the concept of data-driven evaluation modelling and the dynamic formation mechanism of comprehensive packaging efficiency in cold chain logistics. The packaging efficiency in the table grape cold chain was used as an example to evaluate the comprehensive efficiency evaluation index system and data-driven evaluation framework proposed in this paper. Our results indicate that the established methodology can adapt to the continuity of comprehensive packaging efficiency, also reflecting the comprehensive efficiency evaluation of the packaging for different times and distances. Through the evaluation of our results, the differences and the dynamic processes between different final packaging efficiencies at different moments are effectively displayed. Thus, the continuous improvement of a low-carbon system in cold chain logistics could be realized.


2021 ◽  
Author(s):  
Guang-tong Zhou ◽  
Yu-hu Mu ◽  
Yuan-wen Song ◽  
Zhuang-fei Zhang ◽  
Yue-wen Zhang ◽  
...  

Abstract In this study, the synergistic impact of boron, oxygen and titanium on growing large single-crystal diamonds was studied using different concentrations of B2O3 in a solvent-carbon system under 5.5-5.7 GPa and 1300-1500 ℃. The study found that it was difficult for boron atoms to enter the crystal when boron and oxygen impurities were doped using B2O3 without the addition of Ti. However, a high boron content was achieved in the doped diamonds that were synthesised with the addition of Ti. Additionally, boron-oxygen complexes were found on the surface of the crystal, and oxygen-related impurities appeared in the crystal interior when Ti added in the FeNi-C system. The results showed that the introduction of Ti in the synthesis cavity could effectively control the amount of boron and oxygen in the crystal. This not only has important scientific significance for understanding the synergistic influence of boron, oxygen and titanium on the growth of diamond in the earth, but also for the preparation of high-concentration boron or oxygen containing semiconductor diamond technologies.


2021 ◽  
Author(s):  
Le Zhang ◽  
Z. George Xue

Abstract. Coupled physical-biogeochemical models can significantly reduce uncertainties in estimating the spatial and temporal patterns of the ocean carbon system. Challenges of applying a coupled physical-biogeochemical model in the regional ocean include the reasonable prescription of carbon model boundary conditions, lack of in situ observations, and the oversimplification of certain biogeochemical processes. In this study, we applied a coupled physical-biogeochemical model (Regional Ocean Modelling System, ROMS) to the Gulf of Mexico (GoM) and achieved an unprecedented 20-year high-resolution (5 km, 1/22°) hindcast covering the period of 2000–2019. The model’s biogeochemical cycle is driven by the Coupled Model Intercomparison Project 6-Community Earth System Model 2 products (CMIP6-CESM2) and incorporates the dynamics of dissolved organic carbon (DOC) pools as well as the formation and dissolution of carbonate minerals. Model outputs include generally interested carbon system variables, such as pCO2, pH, aragonite saturation state (ΩArag), calcite saturation state (ΩCalc), CO2 air-sea flux, carbon burial rate, etc. The model’s robustness is evaluated via extensive model-data comparison against buoy, remote sensing-based Machine Learning (ML) predictions, and ship-based measurements. Model results reveal that the GoM water has been experiencing an ~ 0.0016 yr−1 decrease in surface pH over the past two decades, accompanied by a ~ 1.66 µatm yr−1 increase in sea surface pCO2. The air-sea CO2 exchange estimation confirms that the river-dominated northern GoM is a substantial carbon sink. The open water of GoM, affected mainly by the thermal effect, is a carbon source during summer and a carbon sink for the rest of the year. Sensitivity experiments are conducted to evaluate the impacts from river inputs and the global ocean via model boundaries. Our results show that the coastal ocean carbon cycle is dominated by enormous carbon inputs from the Mississippi River and nutrient-stimulated biological activities, and the carbon system condition of the open ocean is primarily driven by inputs from the Caribbean Sea via Yucatan Channel.


Author(s):  
Nurtaç Öz ◽  
Meryem Yılmaz ◽  
Ahmet Çelebi

The textile industry is an industry that consumes large amounts of water during production, contains various chemicals in its wastewater, conventional treatment methods are insufficient to reduce the wastewater pollution level, and has colloidal substances and color problems. Membrane bioreactor systems provide high efficiency in the treatment of textile wastewater and dyestuff removal. Removal of dyestuffs and turbidity in real textile wastewater by using a laboratory-scale membrane bioreactor system was studied. Chemical precipitation was not applied before the biological treatment for the removal of color and other pollutant parameters. A hollow fiber microfiltration membrane module was used in the system. Then a combination with an active carbon filter was created to take the color removal to a higher level. The development of the microorganism composition adapted to the textile industry was observed in the biological reactor. The system was operated with an endless sludge age and a hydraulic retention time of 24 hours. Color measurement transparency index parameter DFZ (DurchsichtsFarbZahl) was measured in a spectrophotometer at wavelengths of 436, 525, and 620 nm (nanometers) according to EN ISO 7887 standards. In the microfiltration permeate water, the color removal were found in 436 nm: 91-95%, 525 nm: 94-98%, 620 nm: 96-99%, and in activated carbon permeate water, the color removal in 436 nm: 96-99% at 525 nm: 95-99%, 620 nm: 96-99%, respectively. Due to the physical separation of the membrane, which is the simplest definition, high efficiencies in color removal have been achieved in the system. The activated carbon system combined with the membrane was found higher efficiency in color removal than the microfiltration output.


2021 ◽  
Vol 12 (1) ◽  
Author(s):  
Chichu Qin ◽  
Dong Wang ◽  
Yumin Liu ◽  
Pengkun Yang ◽  
Tian Xie ◽  
...  

AbstractPotassium (K) metal is a promising alkali metal anode for its high abundance. However, dendrite on K anode is a serious problem which is even worse than Li. Artificial SEI (ASEI) is one of effective routes for suppressing dendrite. However, there are still some issues of the ASEI made by the traditional methods, e.g. weak adhesion, insufficient/uneven reaction, which deeply affects the ionic diffusion kinetics and the effect of inhibiting dendrites. Herein, through a unique self-catalysis tribo-electrochemistry reaction, a continuous and compact protective layer is successfully constructed on K metal anode in seconds. Such a continuous and compact protective layer can not only improve the K+ diffusion kinetics, but also strongly suppress K dendrite formation by its hard mechanical properties derived from rigid carbon system, as well as the improved K+ conductivity and lowered electronic conductivity from the amorphous KF. As a result, the potassium symmetric cells exhibit stable cycles last more than 1000 h, which is almost 500 times that of pristine K.


2021 ◽  
Author(s):  
◽  
Ashna Ashneen Khan

<p>Daphnioldhanin A 1.6 is a recent alkaloid obtained from Daphyniphyllum plants. The core structure as shown consists of a 5,5,7 tricyclic ring system, which is a challenging ring system and to date has not been reported in any other natural product. This project focussed on using two cascade approaches in forming this ring system, namely radical addition and cyclisation cascade and carbene cycloaddition cyclisation cascade CCCC. Using the radical approach would require a 5-endo trig cyclisation, which is disfavoured by Baldwin's rules, but has been reported in systems which have an hetereoatom (carbonyl, nitrogen or sulfur) incorporated in the ring. In our case, the 5-endo trig cyclisation is needed in an all carbon containing ring, and preliminary modelling studies have shown that the energy for the 4-exo trig cyclisation product is higher than that of the 5-endo trig cyclisation product. Therefore, the radical approach if successful will eventuate in a novel 5-endo trig cyclisation in an all carbon system. However, due to stability issues with the radical precursors this method had to be abandoned and attention focused on the CCCC approach. For the CCCC approach, rhodium catalysed cascade cyclisation is intended on diazo compound 1.22. The presence of the intramolecular double bond enhances the second cyclisation to occur which will form the 5 and 7-membered ring simultaneously along with oxo-bridge resulting in the functionalised pentacyclic ring system which would be very similar to the proposed 5,5,7 core of Daphnioldhanin A. The desired diazo compound could not synthesised due to failure in forming the anhydride for the acid and future work would be focussed on forming acid derivatives in order to form the diazo compound 1.22 before using rhodium catalysed cyclisation to form the functionalised pentacyclic compound.</p>


2021 ◽  
Author(s):  
◽  
Ashna Ashneen Khan

<p>Daphnioldhanin A 1.6 is a recent alkaloid obtained from Daphyniphyllum plants. The core structure as shown consists of a 5,5,7 tricyclic ring system, which is a challenging ring system and to date has not been reported in any other natural product. This project focussed on using two cascade approaches in forming this ring system, namely radical addition and cyclisation cascade and carbene cycloaddition cyclisation cascade CCCC. Using the radical approach would require a 5-endo trig cyclisation, which is disfavoured by Baldwin's rules, but has been reported in systems which have an hetereoatom (carbonyl, nitrogen or sulfur) incorporated in the ring. In our case, the 5-endo trig cyclisation is needed in an all carbon containing ring, and preliminary modelling studies have shown that the energy for the 4-exo trig cyclisation product is higher than that of the 5-endo trig cyclisation product. Therefore, the radical approach if successful will eventuate in a novel 5-endo trig cyclisation in an all carbon system. However, due to stability issues with the radical precursors this method had to be abandoned and attention focused on the CCCC approach. For the CCCC approach, rhodium catalysed cascade cyclisation is intended on diazo compound 1.22. The presence of the intramolecular double bond enhances the second cyclisation to occur which will form the 5 and 7-membered ring simultaneously along with oxo-bridge resulting in the functionalised pentacyclic ring system which would be very similar to the proposed 5,5,7 core of Daphnioldhanin A. The desired diazo compound could not synthesised due to failure in forming the anhydride for the acid and future work would be focussed on forming acid derivatives in order to form the diazo compound 1.22 before using rhodium catalysed cyclisation to form the functionalised pentacyclic compound.</p>


Fishes ◽  
2021 ◽  
Vol 6 (4) ◽  
pp. 53
Author(s):  
Yi Liu ◽  
Xinmeng Wang ◽  
Wenguang Wu ◽  
Jun Yang ◽  
Ningning Wu ◽  
...  

The shellfish–algae mode of integrated multitrophic aquaculture (IMTA) is a sustainable aquaculture method that benefits the environment and the carbon cycle. However, most current shellfish–algae aquaculture modes are based on the expansion of kelp aquaculture. Due to the low tolerance of kelp to high temperatures, integrated shellfish–algae aquaculture areas often become shellfish monocultures in summer, which may lead to both high mortality rate of shellfish and to economic loss while causing serious environmental harm via eutrophication, decreases in dissolved oxygen (DO), and decreases in pH. In this study, we investigated the effects of different ratios of seaweed (Gracilaria lemaneiformis), which is tolerant of high temperatures, to Japanese scallop (Patinopecten yessoensis) on water quality and environmental parameters. A two-day small-scale enclosure water body experiment was conducted in Sanggou Bay (Shandong, China) in August 2019. The results demonstrated that culturing shellfish alone significantly affected pH, DO, eutrophication, and other environmental indicators, as well as the carbonate system. The negative environmental impact of the shellfish–algae aquaculture system was much smaller. However, too high a proportion of algae might consume excessive amounts of dissolved inorganic nitrogen (DIN) and nutrients, while too low a proportion of algae might not fully absorb the nutrients released by the cultured shellfish, in turn leading to an increased risk of eutrophication. The shellfish–algae aquaculture system not only improved the inorganic carbon system, but also the organic carbon system. At the end of the experiment, all the parameters of the inorganic carbon system had decreased significantly, while all the parameters of the organic carbon system had increased significantly. The results of this study illustrate the need to include macroalgae rotations in summer, and that an appropriate ratio of shellfish to algae is necessary to achieve a sustainable aquaculture system. Moreover, this research has also confirmed the importance of the future and related research in the actual production, which will provide useful information to guide governmental strategies for summer aquaculture rotations and insight into the controversy concerning whether aquaculture is a carbon source or sink.


2021 ◽  
Vol 2057 (1) ◽  
pp. 012103
Author(s):  
N N Konobeeva ◽  
M B Belonenko

Abstract In this paper, we investigate electromagnetic pulse propagation in a medium with impurity carbon nanotubes, which are associated with the acoustic subsystem. The electron spectrum for the carbon system is obtained from the model that takes into account Coulomb impurities. Based on the Maxwell's and the wave equations for the vector of the medium displacements, we obtain the effective equations for the vector potential of the electromagnetic field and the component of the displacement vector of the medium. The dependence of the pulse shape on the various system parameters is analyzed.


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