Huge Room Research Articles

A 1750nm thulium-doped optical fiber laser design: Theoretical model and code simulation

This article mainly studies the physical model design and code simulation of a thulium-doped fiber laser that outputs 1750nm laser. The optical fiber laser has been widely used due to its excellent performance compared with other solid-state laser devices. Among all types of fiber lasers, ytterbium-doped fiber lasers possess the highest output power, whereas they seem to be impractical when an output laser with a longer wavelength is required. However, Thulium-doped lasers have huge room for development to solve the problem, whose unique center wavelength characteristics provide them with huge utilization value. This article shows the electronic transition process a of thulium-doped laser and the power transmission diagram in the fiber. Its rate equation and power equation are also listed below. Through paper retrieval and data extraction, the values of laser parameters can be accurately confirmed, and its power curve can also be obtained through simulation. After analyzing the data obtained from the simulation, the working principle of the fiber laser was intuitively displayed, and the performance of the system was further evaluated. Last but not least, several limitations of this experiment will also be discussed, in order to explore the system more thoroughly.

Unsupervised spectral reconstruction from RGB images under two lighting conditions.

Unsupervised spectral reconstruction (SR) aims to recover the hyperspectral image (HSI) from corresponding RGB images without annotations. Existing SR methods achieve it from a single RGB image, hindered by the significant spectral distortion. Although several deep learning-based methods increase the SR accuracy by adding RGB images, their networks are always designed for other image recovery tasks, leaving huge room for improvement. To overcome this problem, we propose a novel, to our knowledge, approach that reconstructs the HSI from a pair of RGB images captured under two illuminations, significantly improving reconstruction accuracy. Specifically, an SR iterative model based on two illuminations is constructed at first. By unfolding the proximal gradient algorithm solving this SR model, an interpretable unsupervised deep network is proposed. All the modules in the proposed network have precise physical meanings, which enable our network to have superior performance and good generalization capability. Experimental results on two public datasets and our real-world images show the proposed method significantly improves both visually and quantitatively as compared with state-of-the-art methods.

Efficient and Shape-Sensitive Manipulation of Nanoparticles by Quasi-Bound States in the Continuum Modes in All-Dielectric Metasurfaces.

Current optical tweezering techniques are actively employed in the manipulation of nanoparticles, e.g., biomedical cells. However, there is still huge room for improving the efficiency of manipulating multiple nanoparticles of the same composition but different shapes. In this study, we designed an array of high-index all-dielectric disk antennas, each with an asymmetric open slot for such applications. Compared with the plasmonic counterparts, this all-dielectric metasurface has no dissipation loss and, thus, circumvents the Joule heating problem of plasmonic antennas. Furthermore, the asymmetry-induced excitation of quasi-bound states in continuum (QBIC) mode with a low-power intensity (1 mW/µm2) incidence imposes an optical gradient force of -0.31 pN on 8 nm radius nanospheres, which is four orders of magnitude stronger than that provided by the Fano resonance in plasmonic antenna arrays, and three orders of magnitude stronger than that by the Mie resonance in the same metasurface without any slot, respectively. This asymmetry also leads to the generation of large optical moments. At the QBIC resonance wavelength, a value of 88.3 pN-nm will act on the nanorods to generate a rotational force along the direction within the disk surface but perpendicular to the slot. This will allow only nanospheres but prevent the nanorods from accurately entering into the slots, realizing effective sieving between the nanoparticles of the two shapes.

Deep Unsupervised Active Learning on Learnable Graphs.

Recently, deep learning has been successfully applied to unsupervised active learning. However, the current method attempts to learn a nonlinear transformation via an auto-encoder while ignoring the sample relation, leaving huge room to design more effective representation learning mechanisms for unsupervised active learning. In this brief, we propose a novel deep unsupervised active learning model via learnable graphs, named ALLGs. ALLG benefits from learning optimal graph structures to acquire better sample representation and select representative samples. To make the learned graph structure more stable and effective, we take into account k -nearest neighbor graph as a priori and learn a relation propagation graph structure. We also incorporate shortcut connections among different layers, which can alleviate the well-known over-smoothing problem to some extent. To the best of our knowledge, this is the first attempt to leverage graph structure learning for unsupervised active learning. Extensive experiments performed on six datasets demonstrate the efficacy of our method.

Discovery of a far-red carbazole-benzoindolium fluorescent ligand that selectively targets mitochondrial DNA and suppresses breast cancer growth

G-quadruplex (G4) formation was considered to be more prevalent in the mitochondrial DNA (mtDNA) of cancer cells compared with normal cells. Stabilization of these G4s may induce mtDNA instability and cause mitochondrial dysfunction and subsequent cell death, which may be treated as a new strategy for cancer treatment. However, few ligands were developed to target mtG4s, leaving a huge room to improve. In this study, we designed and synthesized a series of carbazole-based ligands, among which, BKN-1 was identified as the most promising mitochondrial targeting fluorescent ligand with far-red emission. Then, we demonstrated that BKN-1 may robustly interact with mtG4s via a variety of biophysical, biological experiments. Subsequently, we proved that BKN-1 may cause mtDNA loss, disrupt mitochondrial integrity, decrease ATP level and trigger unbalanced ROS, thereby leading to apoptosis and autophagy. Finally, we verified that BKN-1 had good anti-tumor activity in both cellular and in vivo models. Altogether, this study provided a dual-function ligand that may not only track the formation of mtG4s but also induce mitochondrial dysfunction, which may be developed into an applicable chemical tool for investigating the structure and function of mtG4s, and moreover, an effective therapeutic agent for cancer interference.

Biological transmission in a magnetized reactive Casson–Maxwell nanofluid over a tilted stretchy cylinder in an entropy framework

Biological transmission (or bioconvection) offers a huge room for studying the interplay between microorganisms and fluid dynamics. The understanding of bioconvection is relevant for studying microbial ecology, population dynamics and exploring the behaviour of microorganisms in complex environments. The objective of this research work is to delve into the physical and biochemical aspects of bioconvection in a magnetized Casson–Maxwell nanofluid containing gyrotactic microorganisms. The investigation is conducted on a tilted elongated cylindrical surface, taking into account the presence of entropy generation. Arrhenius activation energy and slip and convective boundary conditions are novel aspects of this research. The current model invokes the impacts of thermophoresis diffusion, and Brownian motion impacts using the Buongiorno model. The Casson–Maxwell fluid model is employed to expound the rheological behaviour of non-Newtonian nanofluids with the migration of gyrotactic microorganisms. The similarity functions are used to convert the model equations and the related boundary conditions into dimensionless form. The insightful numerical results are developed by implementing the ND Solver in Mathematica, providing valuable insights into the velocity, thermal, concentration, and microorganism fields, as well as the rate of entropy generation and other engineering quantities. Outcomes are presented as graphs and tables for further analysis and discussion. The computational findings unravel several significant contributions of influential model parameters. The Lorentz force and porosity are found to create a drag force that deters the fluid pace, while the reverse trend holds for the fluid temperature. Higher activation energy results in a growth in the concentration field. A larger Peclet number leads to a decline in microorganism density. Furthermore, motile microorganisms’ density and swimming speed significantly influence entropy inflation. A 10% increase in magnetic strength results in a 1.47% increase in skin friction for the Casson fluid model and a 1.32% increase in skin friction for the Casson–Maxwell fluid model. This study contributes to understanding bioconvection in reactive Casson–Maxwell nanofluids with gyrotactic microorganisms and sheds light on entropy production in biological systems.

Refractive index improvement of commercial chalcogenide glasses by external doping with Ag and Pb

The refractive index of commercial chalcogenide glasses (ChGs) available in the market is generally 2.4 to 2.7, which is relatively low and has huge room for improvement. In this paper, different ratios of Ag/Pb were doped into commercial glasses by the melt-quenching method to substantially increase their refractive index. The refractive index of the commercial Ge28Sb12Se60 glass was increased from 2.6 to 3.05 by external doping with 20 atomic percentage (at%) of Ag. And the refractive index of commercially available Ge33As12Se55 glass was increased from 2.45 to 2.88 by external doping with 9 at% of Pb. These improvements effectively reduce the thickness of commercial lenses at the same radius of curvature and focal length. The physical and optical properties of commercial glasses doped with Ag/Pb in different proportions were systematically characterized.

A self-intensified inverted evaporation model constructed by high entropy spectrally selective absorber coating (SSAC) for brine water concentration

One strategy proposed before for applying spectrally selective absorber coating (SSAC) is to design separating structure for dividing the photo-thermal layer with steam generation layer. However, this separation concept faces paradox between salt-prevention ability and heat conduction loss, still has huge room for evaporation performance improvement. Herein, we designed an inverted evaporation model which horizontally deploys a high entropy spectrally selective absorber coating (SSAC) by adhering it upon upside of cloth that possessing strong water absorbing capacity. In the function of self-intensified convective airflow effect, this SSAC-assembled inverted evaporation model can achieve super high productivity (4.98 kg m−2 h−1). Resorting to hydromechanics-based analysis method comes to a conclusion that it probably the pressure difference that gives rise to promotion of steam generation, thus realizing the high-efficiency steam generation in inverted evaporation model. By jointly introducing the hanging structure for desalination, the concentrated brine water can be simultaneously collected through dripping from the bottom of the surface without the interface being solid-salt blocked. This work demonstrates the great potential of SSAC-based hanging and inverted evaporation structure for long-term practical desalination and promising application in separation industry.

Making waves: Why do we need ultra-permeable nanofiltration membranes for water treatment?

Over the last few decades, developing ultra-permeable nanofiltration (UPNF) membranes has been a focus research area to support NF-based water treatment. Nevertheless, there have been ongoing debates and doubts on the need for UPNF membranes. In this work, we share our perspectives on why UPNF membranes are desired for water treatment. We analyze the specific energy consumption (SEC) of NF processes under various application scenarios, which reveals the potential of UPNF membranes for reducing SEC by 1/3 to 2/3 depending on the prevailing transmembrane osmotic pressure difference. Furthermore, UPNF membranes could potentially enable new process opportunities. Vacuum-driven submerged NF-modules could be retrofitted to existing water/wastewater treatment plants, offering lower SEC and lower cost compared to conventional NF systems. Their use in submerged membrane bioreactors (NF-MBR) can recycle wastewater into high-quality permeate water, which enables energy-efficient water reuse in a single treatment step. The ability for retaining soluble organics may further extend the application of NF-MBR for anaerobic treatment of dilute municipal wastewater. Critical analysis of membrane development reveals huge rooms for UPNF membranes to attain improved selectivity and antifouling performance. Our perspective paper offers important insights for the future development of NF-based water treatment technology, which could potentially lead to a paradigm shift in this burgeoning field.

Development of waste heat recovery technology from steel slag

The temperature of molten steel slag produced by the steelmaking process is 1500°c~1700°c, and the total amount of energy contained is considerable. Therefore, the efficient recovery and utilization of sensible heat of steel slag has always been the focus of attention of the metallurgical field all over the world. However, at present, the average recovery rate of waste heat resources per ton of steel in China's iron and steel industry is less than 26%, while the sensible heat recovery rate of various molten slag (including steel slag) is only 1.6%. There are huge room and a broad market for improvement.

Analysis of Corporate Financial Statements Based on the Internal and External Environment of the Industry—Take Inner Mongolia Yili Industrial Group Co., Ltd. as an Example

With the rising income level of residents, demographic changes, improved diet structure and upgraded consumption structure, China's dairy market is developing positively and ushering in huge room for development. In the past few years, as the leader of China's dairy industry, Yili shares have gained momentum. This paper selects Yili Co Ltd as the object of analysis, first briefly introducing the company's basic situation, followed by an analysis of the recent situation and development trend of the dairy industry, then applying SWOT strategic analysis methods, then analyzing its financial situation through financial indicators from 2017-2021, and finally making comprehensive recommendations.

Investigation on the Effect of Applying Different Structures on OLED Devices to Its Performance and Quality

OLED is a kind of device that contains multiple organic layers to produce electroluminescence. OLED has the benefit such as the easy process of manufacturing and only needs a low driving voltage which is environmentally friendly. OLED has low thickness and it doesn’t cost a lot of power compared with LED. By making it as a screen, it can be flexible and have a high capability to emit high light intensity. In this case, more and more experts and enterprises are developing and investigating more in this field. Nowadays, OLED is widely used in the manufacture of foldable screen on mobile phones. Besides, OLED still has a huge room to improve. The external quantum efficiency (EQE), which is the ratio of electrons collected to the incident photons, was well acknowledged to be a good indicator for researchers to evaluate the performance in OLED devices. Due to the difficulties on significant improvement on materials used to make OLED, experts put their effort on designing better structures for OLED to increase its percentage EQE. Therefore, in this work, the performance of OLED devices with different structures were compared.

Reviewing the Sehat Sahulat Program

The former government of Pakistan began a program which offered health insurance to those strata of society who otherwise could not afford the costly health facilities offered in Pakistan. The Sehat Sahulat Card was meant to target around 40 million people or 11 percent of the country's population. The program was begun by KP in 2015 and eventually was expanded to include Sindh, Baluchistan, Gilgit Baltistan, Azad Kashmir and the Federal Capital. The program boasted free-of-cost hospitalizations, surgical procedures, maternity services, cardiac issues and procedures etc. but during the early and even the later days of the program, a wide variety of complaints were raised by patients nationwide. Out-patient services, medical tests and medications were not covered. Private hospitals were said to have benefitted more from this program as opposed to public hospitals. The lack of quality control, monitoring and transparency leads to malpractices and corruption in the health sector. Hospitals were found to send bills for the procedure which were in fact not done to insurance companies. In conclusion, this is an ambitious venture which if treated with transparency and monitored closely holds the potential to revolutionize the healthcare industry in Pakistan but there is a huge room for improvement.

Spatial and nonlinear effects of new-type urbanization and technological innovation on industrial carbon dioxide emission in the Yangtze River Delta.

The purpose of this paper is to quantify the level of new-type urbanization and unravel the spatial and nonlinear effects of new-type urbanization and technological innovation on industrial carbon emissions. Although the impact of traditional urbanization levels on carbon emissions has been widely studied, there is still a huge room for optimization, and the impact of new-type urbanization on carbon emissions has not yet been clarified. Selecting 37 cities in the Yangtze River Delta as a research sample, this paper measures the new-type urbanization based on an evaluation system we build. Consequently, we assess the spatial and nonlinear effects of new-type urbanization and technological innovation on carbon emissions by the spatial Durbin model and non-parameter addictive model, respectively. The results indicate that the new-type urbanization and low-carbon city pilot policy have significant spatial spillover effects on reducing carbon dioxide emissions, while the economic growth plays a positive role in increasing carbon emission. As for nonlinear effects, there is a significant inverted "N"-shaped relationship between the level of new-type urbanization and carbon dioxide emissions, while the nexus between technological innovation and carbon emissions is an inverted "U"-shaped relationship. This paper provides a new perspective for confirming the mechanism of the new-type urbanization on carbon emissions. Meanwhile, these findings are of significance for the relevant authorities in China to develop appropriate policy in carbon dioxide emission reduction.

Investigation on harvesting characteristics of convective wind energy from vehicle driving on multi-lane highway

In the previous study, through the comparison of various highways convective wind energy capturing devices (HCWECDs), it is confirmed that the best wind energy capture device (WECD) structure is the combined turbine (CT). On this basis, this study continues to further study the capture efficiency of WECD and the interaction between WECD and the vehicle in the multi-lane working condition of cars and trucks. Seven different working conditions were selected for the study through the driving conditions of the vehicles and the placement of WECD in the highway. Star CCM + software was used to model and analyze various working conditions. The simulation results are compared, and the results show that the highest power coefficient (Cp) of WECD is 28.2% in seven working conditions; WECD placed in the isolation zone has a low wind energy utilization rate for vehicles other than in the overtaking lane; When two cars are driving opposite each other, the wake affects each other, reducing the impact on WECD; The rotation of WECD has little influence on vehicle driving, but when two vehicles drive opposite each other, it can reduce part of the resistance of vehicle driving for a short time. This study makes a little use of the huge wind energy behind the car body, so there is a huge room for improvement.

Efficient solar energy harvesting enabled by high-entropy ceramic nanofilms through a co-sputtering method

Recent advances in high-entropy ceramic nanofilms have unlocked new possibilities for preparing high-performance solar-thermal conversion materials. Due to their species diversity and structure distinctiveness, these materials provide huge room to exploit more appropriate compositions for boosting solar-thermal performance. Herein, we report a spectrally selective absorber based on high-entropy ZrNbMo-Cr-N ceramic nanofilm prepared by magnetron co-sputtering. Enabled by interface interference and intrinsic absorption effects, the as-deposited absorber exhibits a high solar absorptance of 96.3%, suppressed thermal emittance of 18.8%@400 ºС, and solar-thermal conversion efficiency of 85.4% under 400 ºС and 100 suns. Besides, due to the high configuration entropy of the absorption layers, the absorber exhibits superior thermal robustness after annealing at 400 ºС for 7 days. Further, the absorber can be well deposited on various substrates, including flexible cotton. Radiated by simulated sunlight, those absorber shows a good temperature response; in particular, the surface temperature of the absorber on cotton readily increases to 80 ºС with 50 s under 1 sun. Featured with those competitive merits, the high-entropy ceramic nanofilm absorber empowers a distinct paradigm to investigate solar-thermal conversion, rendering it attractive for various solar-thermal applications.

An Overview of the Research Status of Dance Flow in China

This article uses Dance Flow as the keyword to search in China National Knowledge Infrastructure (CNKI), selects eight articles with high correlation, and analyzes the research status of China’s Dance Flow. Master the download, citation, publication time, article type, article source and research method of the article by using the basic analysis method. Master the main research angle and research core of the article by using the content analysis method. Through the basic analysis and content analysis, the characteristics of Dance Flow in China are reflected. Firstly, China’s research on Dance Flow is in its initial stage, and there are few studies that can combine dance status and Flow factors, which lack pertinence and detailed analysis, and there are many fields that can be filled. Secondly, in applying Flow theory to interdisciplinary research on dance, there are few research institutions, so more universities are needed to expand the research perspective and accelerate the integration with the international community. Thirdly, the research methods show diversity. Some studies use statistical analysis methods, and the measurement tools used have the characteristics of international application. However, compared with the empirical studies that generally use statistical analysis in the world, there is still a huge room for expansion. Fourthly, China’s research on Dance Flow has strong practicability, which can lay a foundation for subsequent research and provide a research paradigm.

Case study of cervical cancer prevention in two sub-Saharan African countries: Rwanda and Sierra Leone.

BackgroundCervical cancer is a public health issue of global concern. It is a preventable disease but continues to threaten the lives of women, especially in developing countries in sub-Saharan Africa.MethodsWe selected two African countries in sub-Saharan Africa (the Republic of Rwanda and the Republic of Sierra Leone) to show a good example of cervical cancer prevention and constrains hindering countries from effectively implementing cervical cancer programs. Secondary data were collected from the World Health Organization (WHO), the International Agency for Research on Cancer (IARC), the Global Burden of Cancer (GLOBOCAN), the United Nations Development Programme (UNDP), and the World Bank and from official websites of the selected countries. A descriptive analysis method was used to source data and compare variables such as the associated factors, disease burden, prevention programs, health workforce, success factors, and challenges.ResultsRwanda achieved 93.3% human papillomavirus (HPV) vaccination of the three doses vaccinating girls in class 6, as a result of effective school-based platform delivery system and community partnership to identify girls who are out of school. Rwanda reduced the historical two-decade gap in vaccine introduction between high- and low-income countries. The country also introduced a nationwide cervical cancer screening and treatment program. An impressive decreased cervical cancer incidence rate in Rwanda in recent years was observed. Sierra Leone lags behind in terms of almost all cervical cancer prevention programs. Therefore, Sierra Leone needs more efforts to implement cervical cancer intervention programs at the national level, including HPV vaccination, and train and increase the number of health professionals, treatment, and palliative care services to accelerate cervical cancer activities.ConclusionThe disease burden of cervical cancer for Rwanda and Sierra Leone is heavy. There remains huge room for improvement in preventing and controlling cervical cancer in these countries. The goal of cervical cancer elimination would not be feasible in countries without the awareness and will of the policymakers and the public, the compliance to fund cervical cancer programs, the prioritization of cervical cancer activities, the availability of resources, the adequate health workforce and infrastructure, the cross-sectional collaboration and planning, inter-sectorial, national, regional, and international partnerships.

Embodied carbon emissions and mitigation potential in China's building sector: An outlook to 2060

In China's building sector, annual embodied carbon emissions (EC) account for a larger proportion than operational emissions, unlike in developed economies. Investigating future EC trajectories, possible abatement potential, and roadmaps can better guide the low-carbon development of the building sector to tackle climate change. This study proposes a bottom-up building EC model, based on the dynamic building stock turnover model and process-based life cycle assessment model, to simulate China's building EC by 2060 under different policy scenarios. The abatement potential of various factors is discussed through the decomposition model and supplementary scenarios. Results indicate that building EC have reached the peak plateau, and by 2060, under the baseline scenario, will be 49% lower than 2020 levels. There is huge room for emission reduction, and the cumulative mitigation ranges from 20.9 to 45.3 billion tCO2 for alternative development scenarios between 2021 and 2060. New building area and material emission factors are the greatest contributors to mitigation potential. Therefore, controlling construction scale and reducing material supply-side emissions are critical strategies for alleviating building EC. Moreover, measures to extend the reasonable service life of existing and new buildings should be implemented as soon as possible to decrease unnecessary waste and emissions.

Consumption Behaviour of Poor Consumers: A Bibliometric and Content Analysis

The poor people segment has gained considerable scholarly attention, particularly after eight scholars established it as an untapped market. This study attempts to understand the nine consumption behaviours of a poor consumer. Therefore, we collate 384 scholarly papers indexed in the Scopus database, published during the period 1975–2020. Both evaluative and bibliometric relationship techniques, namely, Biblioshiny and VOSviewer, are utilized to understand the domain’s progress in the past 45 years. Besides this, content analysis is conducted via hand search to identify the most utilized research methods, popularly applied theories and most explored contexts. Results show that research in this field has grown exponentially, particularly after 2007, with research focusing on low-income consumers, bottom-of-pyramid consumers and mobile money users. The findings indicate this domain demonstrates skewed development, and there is a huge room for future studies.