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Abstract Electronic waste (e‐waste) contains substantial quantities of valuable precious metals, particularly gold (Au). However, inefficient metal recovery leads to these precious metals being discarded in landfills, causing significant water and environmental contamination. This study introduces a two‐dimensional (2D) electrode with a layered graphene oxide membrane functionalized by chitosan (GO/CS). The GO/CS membrane acts as an ion‐selective layer and demonstrates capabilities in the electrochemical extraction and reduction of Au ions. The multiple functional groups of GO and CS offer high cooperativity in ion extraction and reduction, achieving 95 wt.% extraction efficiency within 10 min. The simultaneous extraction and electrocatalytic reduction of Au ions within the membrane leads to the formation of ready‐to‐use metallic Au forms such as chips and sensors. Such an approach eliminates the processing steps required to convert extracted gold into functional products, reducing time, cost, and energy. This direct formation of usable Au components enhances the efficiency of the recovery process, making it economically viable and environmentally sustainable. The gold mining market is projected to be valued at $270 billion by 2032, with the recycling segment reaching $10.8 billion, highlighting the substantial benefits and economic potential of efficient e‐waste recycling technologies.

The paper presents a study on the fabrication of a lightweight acoustic hyperbolic paraboloid (HyPar) diaphragm using self-assembly nanoarchitectonics. The diaphragm is composed of a polyacrylonitrile (PAN) network combined with graphene oxide (GO) nanolayers. Spray coating is employed as a fabrication method, providing a simple and cost-effective approach to create large-scale curved diaphragms. The results demonstrate that the PAN/GO diaphragm exhibits acoustic performance comparable to a commercially available banana pulp diaphragm while significantly reducing weight and thickness. Notably, the graphene-based diaphragm is 15 times thinner and 8 times lighter than the commercial banana pulp diaphragm. This thinner and lighter nature of the graphene-based diaphragm offers advantages in applications where weight and size constraints are critical, such as in portable audio devices or acoustic sensors.

The use of collaborative robots (Cobots) for materials development in chemical laboratories is currently of high priority. Herein, the Cobot is used for autonomous continued analysis and synthesis of graphene oxide–polyethyleneimine‐based membrane to unify a method and prospects for big data collection are shown. Membranes have already demonstrated a selective affinity to potassium cations and promised to adjust permeability for other cations by changing pH. The Cobot allows a variation of membrane properties by its composition modification. The present strategy combines a novel perspective of material production by Cobots and the application of machine learning. Moreover, the current approach can be adapted for different modern chemical laboratories for various scientific research, and the proper workflow is provided.

Sustainable structural design, utilizing material to imitate natural biological systems, presents both promise and challenges. By avoiding interfacial problems encountered in composite counterparts, such designs offer self-adaptive materials for smart housing and green architecture, etc. In this study, we demonstrate the feasibility of large-scale self-assembly of graphene oxide (GO) flakes into anisotropic films through a simple blade coating technique. Through the application of blade coating to a highly concentrated nematic GO suspension, we successfully fabricate GO films with morphological gradient and patterning. Additionally, we propose a statistical analysis method utilizing scanning electron microscopy (SEM) images for the characterization of materials with macroscopic surface morphology. Furthermore, we explore the application of these GO films as low-dimensional soft actuators, revealing their outstanding stimuli-responsive performance and self-adaptation to environment. Such robust and flexible films can be used as integral building elements in the bioinspired design of sustainable smart housing facilitating remote robotization and sensing capabilities.

This commentary article discusses several examples of inaccurate information about the Hmong presented in contemporary materials produced by school district staff and/or published by mainstream publishers in the United States for use with the K-12 market to teach about Hmong culture and history.

In the past 30 years various accounts of Hmong history have emerged from Hmong and non-Hmong scholars working in the United States, other Diaspora countries and Asia. This short commentary paper examines and addresses some of the questions that have arisen from the many versions of Hmong history in China being circulated among the Hmong of the United States.

This paper consists of observations made from my two and a half month visit to the Hmong in Thailand, Laos, Vietnam and China. As such, it contains two parts. The first part is my observation of the Hmong in Asia and their common issues. The second part is a photo essay of the visit to the Hmong in Asia, covering issues discussed in the paper. Although I did visit other subgroups of the Miao, such as the Hmu in Guizhou and Qo Xiong in Hunan, this paper covers only the Hmong, whom I hope will be better presented and discussed as a result of my work. Moreover, the Hmong live in all the above mentioned countries, whereas other subgroups of the Miao live only in China. This paper highlights the socio-economic conditions and educational experiences of the Hmong in the above mentioned countries. It also covers my observations of Hmong civic engagement and other aspects of their social and political lives in the respective countries.

This author attended the first day of the 2005-06 Hmong New Year in Fresno which was held during the week of December 26 to 31, 2005; and found it to be strongly influenced by commercial, political and informational/educational activities. This was the 30th annual Hmong New Year event celebrated in the United States and it appears to have developed itself into a unique Hmong American festival. It included many elements and traditions from the pre-1975 New Year of the Hmong of Laos. This includes the youth displaying their Hmong traditional costumes, the ball tossing, and the singing of traditional Hmong songs. On the other hand, this New Year event was also dominated by commercial, entertainment, political and informational/educational activities that appeared to be influenced by the American and Western concepts of the market economy, technology and freedom of expression. The Hmong New Year in the United States has become a festival that embraces two cultures, nurtured by the Hmong Diaspora and the long-time Hmong strengths of adaptability and flexibility.

This paper is intended to broadly explore both the achievements and needs and problems of the diverse Hmong American community across the United States, with a particular emphasis on felt needs and problems. Felt needs and problems are defined as needs and problems ”perceived by individuals experiencing the problem, may be equated with want and are phenomenological in character” (Cox, Erlich, Rothman & Tropman, 1984, p. 9). Taken from this perspective, among the problems and needs discussed in this paper are those that were identified by key informants or members of the Hmong American community, who live in the community and are well informed of the acute issues experienced by their fellow co-ethnics. Felt needs and problems, in addition to other needs, are very important issues for Hmong community gatekeepers, social workers and service providers to know and understand, in order to effectively work with a particular community (Cox, et al. 1984). The phenomena identified in this exploratory paper are intended to provide a departure point for researchers undertaking future relevant studies of social issues important to the Hmong community.

Obituary and bio for Nhiavu Lobliayao.

Despite the many studies of Hmong in the United States over the past two decades, little is known specifically about how mature Hmong men are adapting to life following their resettlement. Anecdotes describing the often dramatic problems mature Hmong men encounter suggest a need to more closely study this population. A variety of factors are said to lead to problems for Hmong men after resettlement. Women are finding it easier to find work outside the home and to learn English. The traditional male role of decisionmaker is increasingly devalued as children seek more independence. Furthermore, since youth often serve as intermediaries between adults and mainstream institutions because of their language skills, this again reverses traditional power relationships. The ability of a male head of household to provide for his family is greatly diminished with even the AFDC checks made out in the mother's name. Too often stories circulate of once powerful military officers and village chiefs living in isolated poverty and dependent on others.

To fully leverage the potential flexibility resources of a source-network-load-storage (SNLS) system and achieve the green transformation of multi-source systems, this paper proposes an economic and low-carbon operation strategy for an SNLS system, considering the joint operation of ladder-type green certificate trading (GCT)–carbon emission trading (CET), and integrated demand response (IDR). Firstly, focusing on the load side of electricity–heat–cooling–gas multi-source coupling, this paper comprehensively considers three types of flexible loads: transferable, replaceable, and reducible. An IDR model is established to tap into the load-side scheduling potential. Secondly, improvements are made to the market mechanisms: as a result of the division into tiered intervals and introduction of reward–penalty coefficients, the traditional GCT mechanism was improved to a more constraining and flexible ladder-type GCT mechanism. Moreover, the carbon offset mechanism behind green certificates serves as a bridge, leading to a GCT-CET joint operation mechanism. Finally, an economic low-carbon operation model is formulated with the objective of minimizing the comprehensive cost consisting of GCT cost, CET cost, energy procurement cost, IDR cost, and system operation cost. Simulation results indicate that by effectively integrating market mechanisms and IDR, the system can enhance its capacity for renewable energy penetration, reduce carbon emissions, and achieve green and sustainable development. [ABSTRACT FROM AUTHOR]

At present, the safe operation of integrated energy systems is significantly affected by the considerable uncertainty inherent to wind and photovoltaic power generation. Based on this, this paper proposes an optimal scheduling model for integrated electricity, heat, and hydrogen-based energy systems on distributed robust optimization (DRO). Firstly, a combined heat and power microgrid system considering hydrogen energy systems was constructed based on the thermoelectric cogeneration characteristics of fuel cells and electrolyzers. Then, a data-driven two-stage distribution robust optimization scheduling model is built by combining typical historical data of wind power output, photovoltaic power output, and load. The results show that the distributed robust method reduces the running cost by 6% compared to the deterministic method. The proposed method and model are capable of meeting the demand for thermoelectric loads within the microgrid in a more cost-effective manner, thereby achieving stable and independent operation of the system. [ABSTRACT FROM AUTHOR]

Relying solely on electrical energy storage for energy regulation makes it difficult to provide a stable and efficient energy supply for microgrid systems currently. Additionally, the economic cost of microgrids and the rate of energy use present a challenge that must be addressed. A strategy for allocating capacity for multi-energy microgrids that takes energy efficiency and hydrogen energy into account is offered as a solution to the aforementioned issues. Initially, the construction of the multi-energy microgrid system takes into account the thermoelectric coupling properties of hydrogen energy devices. Second, the system's energy utilization level is measured using the exergy efficiency analysis. Next, the multi-objective capacity optimization allocation model of the multi-energy microgrid system is established, with the exergy efficiency and system economic cost serving as the objective functions. Lastly, the multi-objective model is solved using the ε -constraint approach to find the Pareto frontier, and Technique for Order Preference by Similarity to an Ideal Solution is employed for decision-making. The example results demonstrate that, when compared to a traditional microgrid using electric energy storage, the proposed model can effectively lower the system's economic cost and improve exergy efficiency. Additionally, multi-objective capacity optimization can be used to strike a balance between exergy efficiency and the system's economic cost. For relevant studies on the capacity allocation of multi-energy microgrids, this work can be a helpful resource. [ABSTRACT FROM AUTHOR]

Currently, high levels of output stochasticity in renewable energy and inefficient electrolyzer operation plague IESs when combined with hydrogen energy. To address the aforementioned issues, an IGDT-based economic scheduling strategy for integrated energy systems is put forth. Firstly, this strategy establishes an IES consisting of coupled electricity, heat, hydrogen, and gas taking the hydrogen production electrolyzer's thermal energy utilization into account. Second, to minimize the system's overall operating costs, a deterministic scheduling model of the IES is built by taking into account the stepped carbon trading mechanism and the integrated demand response. Lastly, an optimal dispatch model is built using the information gap decision theory under the two strategies of risk aversion and risk seeking, taking into account the uncertainty of renewable energy generation. CPLEX is the solver used to solve the proposed model. After taking into account the effective use of thermal energy from the electrolyzer and loads demand response, the results show that the system carbon emission is reduced by 2597.68 kg and the operating cost is lowered by 44.65%. The IES scheduling model based on IGDT can effectively manage costs while maintaining system risk control, all while accommodating decision-makers' varying risk preferences. This study can provide a useful reference for the research related to the scheduling of the IES low-carbon economy. [ABSTRACT FROM AUTHOR]

Corrosion is one of the major issues for sustainable manufacturing globally. The annual global cost of corrosion is US$2.5 trillion (approximately 3.4% of the world's GDP). The traditional ways of corrosion protection (such as barriers or inhibiting) are either not very effective (in the case of barrier protection) or excessively expensive (inhibiting). Here, we demonstrate a concept of nanoreactors, which are able to controllably release or adsorb protons or hydroxides directly on corrosion sites, hence, selectively regulating the corrosion reactions. A single nanoreactor comprises a nanocompartment wrapped around by a pH-sensing membrane represented, respectively, by a halloysite nanotube and a graphene oxide/polyamine envelope. A nanoreactor response is determined by the change of a signaling pH on a given corrosion site. The nanoreactors are self-assembled and suitable for mass-line production. The concept creates sustainable technology for developing smart anticorrosion coatings, which are nontoxic, selective, and inexpensive. [ABSTRACT FROM AUTHOR]