During carbothermal production of metallurgical-grade silicon in submerged arc furnaces (SAF), a significant amount of fine SiO2 particles, called silica fume, are formed along with silicon in the reduction process. Silica fume is formed in a semiclosed furnace hood, where the process gas meets excessive amounts of air to ensure complete combustion and sufficiently low temperatures for the off-gas system. The silicon yield describes how much silica fume is formed and determines how much carbon the process needs, which is expressed as R1. (1)

Initially a waste product, silica fume is today used as an important addition to concrete, refractory materials, and a range of other products and hence is considered an important byproduct of the silicon production process. (2) The added fine silica fume, usually with a specific surface area (SSA) around 20 m2/g, acts as a pozzolan in concrete and adds strength, decreases thermal expansion, and increases corrosion resistance in the concrete product. The purity of the silica fume is important for the end-product application. Elemental silicon is an impurity that should be limited in silica fume due to safety. Silicon can react with pore water in the concrete and slowly evolve hydrogen or hydrogen sulfide, according to R2 or R3. This could lead to dangerous H2 or H2S concentrations if it occurs in closed-off concrete installations with limited air circulation. A review of the effects of silica fume in concrete can be found in the guide by the American Concrete Institute. (3)

Carbothermal reduction of silica leads to emissions of CO2 through combustion of the CO formed in R1. Carbon capture (CC) may be an option for reducing the footprint of silicon production, either by sequestration (CCS) or utilizing the captured CO2 for purposes that displace the use of other fossil materials (CCU). There are several ways CCU/S can be implemented, and an extensive review of the subject has been done by Gür. (4) A common way of classifying CC is by pre-combustion capture, oxyfuel combustion, or post-combustion capture. Pre-combustion capture, which is the method of capturing CO2 from the fuel before combustion, is not an option for silicon production as solid carbon is needed for the reduction process of SiO2 into Si. For CC through oxy-fuel combustion, air is replaced with O2 under combustion, avoiding diluting N2 and giving an off-gas with a very high concentration of CO2. This could be an option for silicon production but requires closing of the furnace. Previous attempts at closing the furnace have been done by Elkem in 1981 (5) and by Dow in the 1990s, (6,7) with a motivation of improving the process and producing a sellable combustion gas, consisting mainly of CO and some H2. These efforts showed a wide range of challenges that needed to be solved to make a closed furnace process viable. One of these challenges was maintaining the product quality of the silica fume.

To cope with the serious situation of climate change, carbon emission reduction has become the common consensus worldwide. (1) Many countries have set a goal for carbon neutrality. (2) Solar photovoltaics (PV) has the greatest potential to achieve this goal; PV power accounts for about 20 to 60 percent of the global electricity scenario in a largely or fully decarbonized context by 2050. (3)

Due to the lower power density of PV power compared to fossil energy, a large amount of land will be required to accommodate PV facilities in the future. (4) The management of solar parks as pasture is an ideal option in terms of reducing emissions from land use change and reducing the impact on native species in the hosting ecosystem. (5) Grasslands account for 30% of the world’s land area and have great potential to meet the demand for PV arrays, especially the deployment of PV arrays in grasslands, which will not preclude the ability of sheep to graze on the land around the PV arrays and provide shelter for sheep by the panels. (6−9) Therefore, grassland ecosystems rank highly in terms of their potential for PV array deployment. (10−12)

In recent years, the installed PV capacity in Northeast China has increased rapidly. (13) For instance, the total planned developable capacity of PV projects in Jilin Province amounts to 36.14 GW (by 2035), and dozens of concentrated solar power systems have been built in this province.

The sustained flux global warming potential (SGWP) and the sustained flux global cooling potential (SGCP) are important indexes to measure a substance released into the atmosphere, (14) and they are also the key life cycle impact indicators to quantify the environmental performance of solar parks. (15) For PV modules manufactured in Europe and China, the life-cycle greenhouse gas (GHG) footprints were estimated to be 37.3 and 72.2 g CO2-eq kW h–1, respectively. (16) Previous studies have considered the GHG footprint during the production, transportation, and waste treatment processes of solar parks. (17−19) However, such changes in land use may affect soil processes, plant community dynamics, (20) and GHG emissions in grassland ecosystems. Therefore, there is a lack of accurate measurements of GHG emissions during the operation periods of solar parks, which may lead to an inaccurate assessment of the GHG footprint.

Reducing GHG emissions is one of the main advantages of PV power generation. (21) In simulation studies, research in Poland has calculated that a kilowatt of installed solar power saves up to NO2 by 16 kg, SO2 by 9 kg, and CO2 by 600–2300 kg compared to fossil fuels. (22) A 50 MW solar park could reduce CO2 emissions by up to 45 million tons compared with fossil fuels per year in Egypt. (23) Another report indicated that PV power generation was expected to reduce 46.5 Tg of CO2 emissions compared with 600 MW of coal-fired supercritical units in China. (24)...

The influence of the solar park on hosting ecosystems can be summarized as follows: first, solar park construction involves clearing and grading the soil surface, digging trenches to lay electric cables, which may contribute to part of vegetation loss, soil compaction, and increased erosion risks. (20) Second, solar park management may involve regular mowing and cleaning to avoid fire hazards and the loss of power generation caused by vegetation shading and dust accumulating on the PV panels. (26) Third, the operation period of solar parks in hosting ecosystems results in land use changes; large-scale PV arrays in solar parks have the potential to affect land surface albedo, (27) cause shading (28,29) and intercept precipitation. (30) Changes in surface albedo and soil moisture may directly and indirectly affect soil temperature. (31−33) The shading and intercept precipitation of PV panels may alter soil moisture patterns in grasslands. (34) Previous research found that shading by PV panels in desert locations might raise the soil temperature during the winter but reduce it during the other three seasons, and soil moisture in the shading zone was significantly higher than in ambient zones. (35) The sheltered zone was cool and dry in summer, but the gap zone between the PV panels was colder than the ambient zone and sheltered zone in winter; the PV arrays significantly affected the aboveground plant biomass and the plant species on the grassland. (10)

Figure 1. (a) Location of the Honghua solar park in the Songnen Grassland, Northeast China. (b) Three experimental zones of Ambient (the reference zone outside the PV arrays), Gap (the gap zone between the PV panels), and Under (the sheltered zone under the PV panels). (c) Schematic diagram of the PV panel installation. Angle A is the installation inclination of the PV bracket, AB is the length of the inclined surface of the PV panel assembly, and AD is the distance between the front and back row of PV arrays.

Figure 2. Month dynamics of average VPD (a) and PAR receipts (b) in different experimental zones. Ambient, the reference zones outside the PV arrays; Gap, the zones between the PV panels; Under, the sheltered zones under the PV panels.

Figure 3. Soil temperature (ST), soil moisture (SM), pH, total organic carbon (TOC), total nitrogen (TN), carbon nitrogen ratio (C/N), nitrate nitrogen (NO3––N), ammonium nitrogen (NH4+–N), available phosphorous (AP), plant height (Height), coverage (Cover), and density (PD) in the L. chinensis community, Forb community, and A. scoparia community in different experimental zones (Ambient, the reference zones outside the PV arrays; Gap, the zones between the PV panels; Under, the sheltered zones under the PV panels) (mean ± SE). Different letters represent significant differences among different experimental zones (p < 0.05). ns indicates that the difference is not significant.

Figure 4. Temporal variations of CO2 (a) flux, CH4 (b) flux, and N2O (c) flux in different experimental zones during the growing season (mean ± SE). Ambient, the reference zones outside the PV arrays; Gap, the zones between the PV panels; Under, the sheltered zones under the PV panels. Significance levels are as follows: *p < 0.05, **p < 0.01 and ***p < 0.001, ns, no significant difference.

Figure 5. Average fluxes of CO2, CH4, and N2O in the L. chinensis community (L. chinensis), Forb community (Forb), and A. scoparia community (A. scoparia) in different experimental zones (Ambient, the reference zones outside the PV arrays; Gap, the zones between the PV panels; and Under, the sheltered zones under the PV panels) (mean ± SE). Different letters represent significant differences among different experimental zones (p < 0.05). ns indicates that the difference is not significant.

Figure 7. SGWP between ambient zones (Ambient) and PV array zones (a), GHG footprint during operation from the gap zones (Gap) and the shelter zones (Under) under the PV panels in the PV arrays (Eh) (b), and the missing percentage of GHG footprints of PV facilities reported in literature compared to ours (c). Yue:, (16) Mar:, (75) Nia:, (76) Mil:, (77) Lec:, (78) Kim:, (79) Ito:, (80) Hou:, (81) Her:, (82) Bey:, (83) Ber:, (84) Bos:. (85) The significance levels are as follows: *p < 0.05, **p < 0.01 and ***p < 0.001, ns, no significant difference.

Figure 8. SEMs to identify the explanatory variables of CO2 flux (a), CH4 flux (b), and N2O flux (c). Numeric values adjacent to arrows are standardized path coefficients, analogous to relative regression weights, and indicative of the effect size of the relationship (n = 225). Continuous and dashed arrows indicate positive (red color) and negative (green color) effects, respectively. For each model, the proportion of variance explained (R2) and the various goodness-of-fit statistics are shown below the response variables. Significance levels are as follows: *p < 0.05, **p < 0.01 and ***p < 0.001. Abbreviations: Zone, different experimental zones (Ambient, Gap, and Under); PCT, different PCTs (L. chinensis community, Forb community, and A. scoparia community); ST, soil temperature; SM, soil moisture; C/N, soil carbon nitrogen ratio; PD, PD.

The main processes of PV arrays affecting grassland vegetation, such as shading by PV panels, changing the surface temperature and precipitation distribution, and affecting the evaporation of surface water are approximately the same in grasslands at different locations, as demonstrated by previous studies of solar parks in Oxfordshire (UK), (10) the South Moravian Region (CR), (98) and Southern France. (99) China’s grasslands cover 392.8 million ha, accounting for 40% of the national land area. (100,101) The L. chinensis meadow selected for this study is located in the Songnen grassland in Northeastern China, which is the most typical and largest grassland type in China and has good representativeness. Therefore, we are confident that the field results of this study can be largely extended to grasslands in other parts of the world and are of general significance.

Currently, half of the global population lives in water-scarce areas, and this number is likely to increase by 2050. (1) On the one hand, humans depend on freshwater for industrial, domestic, and agricultural uses. On the other hand, human well-being also relies on healthy terrestrial and freshwater ecosystems and ecosystem services. (2) In many areas, human activities already extract freshwater at levels that put affected ecosystems at risk, and global water demand for all uses is predicted to increase by up to 30% by 2050. (3−5) Flow alteration, e.g., by dam construction and water consumption, is one persistent threat to aquatic biodiversity. (6) Water consumption has also been linked to the loss of terrestrial species, e.g., terrestrial mammals, birds, amphibians, and plants. (7,8) A sustainable management of water resources is required, calling for a balance between anthropogenic water consumption and water availability to sustain human development while safeguarding ecosystems. (9)

New integrated approaches and tools are needed to address the challenges posed by multiple, and often conflicting, water needs for humans and ecosystems. (10) Several tools and methods have already been proposed to tackle these issues, including water footprinting, (9,11) planetary boundaries, (12) integrated water resource management, (13) life cycle assessment (LCA), (14−16) and environmentally-extended multi-regional input–output analysis. (17) The integrated nature of hydrological systems requires that the assessment of environmental impacts of water consumption differentiates between water compartments to reflect distributions and renewability levels among water sources. (18) Different compartments interact with varying strengths and over a wide range of geographical and temporal scales with other components of the Earth system, such as the atmosphere, biosphere, and lithosphere. Evaluating the ecological impacts of water management decisions, therefore, requires accounting for the hydrologic processes that determine the relationships between surface and subsurface waters, as surface water, soil water, and groundwater influence one another. (19) Existing life cycle impact assessment (LCIA) models for freshwater consumption characterize the associated damages to ecosystems and human health. (8,14,20−24) However, the interlinkages across water compartments are rarely considered, except for a few studies modeling the recycling and transfer of evapotranspiration and LCIA models quantifying potential impacts on ecosystems...

Figure 1. Cause-effect chain linking water consumption to hydrological indicators and subsequently to ecosystems and freshwater natural resources.

Figure 2. Global maps of water consumption change and resulting depletion factors for streamflow, groundwater compartment storage, soil moisture, and evapotranspiration for 8664 river basins from 1960 to 2000. The effect of water consumption on the different depletion factors is split between positive (left) and negative (right) values for simplicity of representation.

aPositive and negative depletion factors are reported in blue and red, respectively. Consumption change and average groundwater–surface water consumption ratio are reported in parenthesis after the cumulated consumption. The consumption change is relative to the mean value over the period 1960–2000.

Construction has begun of a 23-kilometre-long pipe that will transport nuclear-generated heat from the Haiyang nuclear power plant in China's Shandong province to a wider area, State Power Investment Corp (SPIC) announced. The plant started providing district heat to the surrounding area in November 2020.

A ceremony was held on 4 February in the city of Yantai, near the Haiyang plant, to mark the start of construction of a pipeline to the city of Weihai.

"The heat pipe network marks the official start of China's first long-distance nuclear energy heat supply pipeline network project across prefecture-level cities," SPIC said. "It will realise cross-regional intercommunication and sharing of zero-carbon heat sources."

So far, the nuclear energy heating source project has completed an investment of CNY390 million (USD57 million), the company said. Installation of equipment at unit 2 of the Haiyang plant to extract heat began in July last year and has now been completed. The heating pipe network and pumping station in the plant are now being constructed.

The project is planned to be put into operation before the end of 2023, SPIC said.

The long-distance pipeline will have an annual heating capacity that can reach 9.7 million gigajoules, providing heat to a 13 million square metre area and meeting the needs of 1 million residents. This will replace the consumption of some 900,000 tonnes of coal, reducing carbon dioxide emissions by 1.65 million tonnes.

The Haiyang plant officially started providing district heat to the surrounding area in November 2020. A trial of the project - the country's first commercial nuclear heating project - was carried out the previous winter, providing heat to 700,000 square metres of housing, including the plant's dormitory and some local residents. Earlier in 2020, the project began providing heating to the entire Haiyang city...

Nuclearelectrica has welcomed the adoption of the law approving a support agreement with Romania's government for the proposed units 3 and 4 at the Cernavoda nuclear power plant. The firm said it allows the start of the next phase of the project.

Cosmin Ghita, Nuclearelectrica CEO, said the project would not be able to go ahead "without the involvement of the state and authorities in nuclear energy projects ... today’s vote is a concrete signal for the continuation of this strategic project for Romania, by which we will add another 10 TWh of CO2-free energy to the national energy system after 2031".

He said Nuclearelectrica was looking to combine investment in the new units with refurbishment of unit 1 and development of small modular reactors, saying "efficient, safe and clean nuclear energy will make Romania an example at regional and global level, through various support partnerships associated with major investment projects".

The commitments given by the law include the government taking "the necessary steps to finance the construction of the two reactors, including but not limited to the granting of state guarantees to the project's financiers". It will also be responsible for the implementation of the "Contracts for Difference" support mechanism.

Nuclearelectrica said that the adoption of the law means Phase II of the project can now get under way - which includes steps relating to updating the project budget, structuring financing and getting European Commission approval as well as Nuclear Safety Authorisation for the construction phase and taking the final investment decision to move to Phase III, the construction phase.

The second phase of the project is scheduled to take up to 30 months, with construction estimated to take up to 78 months. Unit 3 is scheduled to start commercial operation in 2030 and Unit 4 the following year...

Women including Marie Skłodowska-Curie, Lise Meitner, Chien-Shiung Wu, and Katharine Way were key pioneers in nuclear science and technology, but today the visibility of women in the nuclear sector remains low. Women make up just one-quarter of people employed in the nuclear sector, and for STEM positions in that field specifically, they also make up just one-quarter of the workforce. About 8,000 of those women responded to an a survey from the OECD Nuclear Energy Agency, and their responses have been captured in Gender Balance in the Nuclear Sector, a new report from the OECD NEA.

March 8, International Women’s Day, is the date the NEA chose to release the first publicly available international data on gender balance in the nuclear sector. William D. Magwood IV, director general of the NEA, kicked off an NEA webinar to introduce the report—the result of three years of effort by an NEA task group. “When the group met for the first time before the pandemic,” he said, “they realized that there was insufficient data to understand the problem. . . . So the group set out to do a survey—two surveys, in fact: a human resources survey and a public opinion survey—and the results of those two surveys are what we have in the report that we're launching today.”

Magwood said he learned a lot in the process. “To me the biggest education wasn't really from the data. . . . It was what I learned along the way as we went through this exercise and talked to women from around the world and heard stories about women in the nuclear sector who had to put up with really unconscionable remarks being made about them by male colleagues in the workplace, which wasn't something I heard once but many, many times throughout this process. I saw from one of our member countries in Europe that the pay differential for the exact same work was 40 percent between men and women. How does that happen in the modern world? I heard things that quite frankly I found shocking and embarrassing and would not have known if we had not gone through this exercise.”

The NEA Gender Balance Task Group concluded that women employed in the nuclear sector want to advance their careers but face challenges such as a lack of flexible work practices for those with family responsibilities as well as gender stereotyping. Despite those challenges, the majority of women surveyed said that they would encourage other women to pursue a career in the nuclear sector. Those women are needed, as nuclear energy is poised for expansion around the world.


Fiona Rayment, chief science and technology officer of the United Kingdom National Nuclear Laboratory, chaired the task group that conducted the study. “With the ever-increasing importance of energy security while minimizing carbon emissions, a solution including nuclear energy is receiving greater focus,” she said. “Meeting these challenges requires a broad range of skills that can be delivered through a neurodiverse workforce, and creating gender balance across the international nuclear sector is a key element in achieving this. My hope is that this report enables the sector to have a springboard to move to greater gender balance in the years ahead, driving the neurodiversity the sector is craving...”

...Collective wisdom: During the report launch webinar, Rayment, described the task group’s plans to create a policy framework that will use the report’s data to track progress with a “strategic framework of attract, retain, and advance.”

There is an opportunity, she said, “to leverage government influence on the nuclear sector, aligning priorities and mobilizing the resources accordingly. In terms of who we're going to target, we're targeting government agencies, contractors, and funding recipients within the nuclear sector. A broad range of organizations are being invited to engage with us and implement this framework going forward.”

Rayment moderated a panel discussion including Melina Belinco, Women in Nuclear (WiN) global vice president and deputy manager of international organizations for the Canadian National Energy Alliance; Yeonhee Hah, vice president for global activities at the Korea Institute of Nuclear Safety; Lisa McBride, vice president and country leader at GE Hitachi SMR Canada and president, WiN Canada; Aditi Verma, assistant professor in the Department of Nuclear Engineering and Radiological Sciences at the University of Michigan; and Neil Wilmshurst, senior vice president of energy system resources at EPRI. The panelists agreed that achieving gender balance within the nuclear sector will be difficult—but achievable.

McBride, whose company recently secured a contract for a small modular reactor new build at the Darlington site in Ontario, said, “I think we need to not overlook the fact that women already do make valuable contributions to this industry. It's important and incumbent upon organizations to profile the critical role that women play, which helps advance and retain. If you can see it, you can be it. . . . We do really complex things in this industry, far more complex than getting an equal seat at the table for women. So to me this is really about being committed to change and understanding what the change journey looks like. Yes, it is hard, but we do harder things than this literally every day in this industry...”

Breast cancer is a common malignancy among women, and its incidence rate is increasing worldwide, irrespective of the country's economic status. In 2020, approximately 2.3 million women were diagnosed with breast cancer, of which 685,000 deaths were reported globally [1]. However, in the past three decades, the mortality rate due to breast cancer has consistently declined in countries with the implementation of screening and local management of early breast cancer, advanced modes of treatment (e.g., surgical removal, therapy, and medication), including the emergence of the adjuvant systemic therapies [2]...

...Breast cancer is a biologically and molecularly heterogeneous disease originating from the breast [3]. Based on the gene expression pattern of four well-established biomarkers, such as estrogen receptor alpha (ERα ), progesterone receptor (PR), human epidermal growth factor receptor 2 (HER-2), and proliferation-associated nuclear antigen (Ki-67), breast cancer tumours have been categorized into five distinct subtypes, i.e., Luminal A and B, Triple-negative, Normal-like, and Her-2 enriched breast cancer [4]. This molecular/clinical subtype classification is often used to decide the appropriate therapeutic strategies and set the critical reference for prognosis [5].

Among the different breast cancer subtypes, triple-negative breast cancer (TNBC) is a heterogeneous set of cancer characterized by no ER/PR and Her-2 protein expression. It is the most aggressive subtype and grows faster than other subtypes. It has a poor prognosis with no effective targeted therapy due to the absence of any receptor status [6,7]. TNBCs mainly affects younger women (less than 50 years of age) with a higher frequency of p53 mutations and at a higher risk of death by distant recurrence, especially during the first 3–5 years of follow-up. Importantly, TNBC metastasizes predominantly to visceral organs than bones, including a higher incidence of cerebral metastases and a higher rate of local relapse in patients than any other subtypes...

...Mass-spectrometry (MS) has found its application in cells, tissue, and biofluids to identify and characterize potential biomarkers. For instance, untargeted proteomics has been employed to investigate potential markers of TNBC in breast cancer tissue [10,11] or biofluids such as serum and plasma [12,13]. Few studies have also reported validated markers for TNBC using MS-based targeted quantitation in blood samples [14] and breast cancer tissue [[15], [16], [17]]. However, only limited information is available on salivary proteomics [[18], [19], [20]]. Their validation could reflect saliva as an adequately complex fluid investigating potential markers in TNBC.

Due to the propensity of ease of collection and enrichment of low abundant proteins in saliva, we used an MS-based label-free untargeted approach for relative quantitation coupled with absolute targeted quantitation using parallel reaction monitoring (PRM)-based assay to investigate potential salivary protein markers associated with TNBC and its metastasis...

...To facilitate the verification and potential translation of these proteins and peptides for clinical application, they were assessed for their diagnostic performance to determine the sensitivity, specificity, and positive/negative predictive values. To this end, we observed that GLST and VYAL with an AUC of 0.84 performed better than the other peptides as individual markers. However, compared to one protein's performance as an individual marker, the five-signature panel with salivary GLST, VYAL, MINL, GPYP, and IPPP achieved better performance in differentiating aggressive TNBC and HS with sensitivity (80%) and specificity (95%) (AUCs of 0.89). Although the machine learning approach has been applied to a relatively smaller cohort of patients, it shows promising generalizability, prompting us to target these groups of peptides in a large cohort of TNBC patients to validate in saliva.

Our study is designed in the context of potential marker discovery in non-invasive bio-fluid saliva from TNBC patients utilizing targeted proteomic assays. While our developed assays are subsequently evaluated across multiple independent cohorts, substantial work is still required by validating these proteins in larger independent patient cohorts, preferably in longitudinally collected samples and additional assay optimizations. Here, we provide the first work utilizing PRM-MS to systematically identify these novel salivary proteins as potential markers to distinguish and indicate TNBC progression in a medium-sized cohort...

A few miles off the intersection of state Route 160 and Tecopa Road, about 10 miles south of Pahrump, lies a 3,000-acre solar farm under development. As you approach the project, bundles of metal fencing are prepped to soon become 10 miles of temporary desert tortoise exclusion fencing.

A team of biologists relocated 139 tortoises from their habitat to make way for the solar panels in the Yellow Pine Solar Project, one of four large solar energy developments initiated in Southern Nevada. The tortoises were moved across the road to Stump Springs in May.


In a span of a few weeks, 30 tortoises were killed, possibly by badgers. Conservationists believe relocation stress made the reptiles more vulnerable and drought caused badgers to look for new sources of prey. Wildlife experts are still looking into the exact cause.

The loss of the tortoises, a threatened species in Nevada since 1990, illustrates the challenges of bringing alternative energy sources to the Mojave Desert while still protecting its biodiversity...