分类： science

Chinese scientists have unveiled a groundbreaking refrigeration technology that simultaneously addresses three critical challenges: carbon emissions reduction, high cooling capacity, and superior heat transfer efficiency. Published in the prestigious journal Nature, this discovery represents a potential paradigm shift in thermal management systems.

The research team, led by Dr. Li Bing from the Chinese Academy of Sciences’ Institute of Metal Research, identified a novel dissolution barocaloric effect in an NH₄SCN salt solution. This innovative approach leverages pressure changes to trigger dramatic temperature fluctuations. When pressure is applied, solid NH₄SCN precipitates and releases heat; during depressurization, the salt rapidly dissolves while absorbing substantial thermal energy.

Laboratory results demonstrate remarkable performance characteristics: at room temperature, the solution’s temperature plummets by nearly 30 degrees Celsius within just 20 seconds. The cooling efficiency increases further at elevated temperatures, significantly outperforming existing solid-state caloric materials that have struggled with heat transfer limitations.

This breakthrough unifies the refrigerant and heat-transfer medium into a single fluid system, eliminating the efficiency compromises that have hampered previous environmentally friendly cooling technologies. The research team has designed a four-step cyclic system incorporating pressurization for heating, environmental heat dissipation, depressurization for cooling, and cooling capacity delivery.

Computational simulations reveal extraordinary potential: each cycle achieves 67 joules of heat absorption per gram of solution with an unprecedented 77 percent energy efficiency rating. This performance metric suggests strong commercial viability, particularly for large-scale applications such as data center cooling systems where thermal management represents both a technical challenge and significant operational expense.

The timing of this innovation coincides with growing global concerns about cooling-related energy consumption. According to the United Nations Environment Programme’s Global Cooling Watch 2025, worldwide cooling demand may triple by 2050 compared to 2022 levels, potentially doubling associated greenhouse gas emissions without technological intervention.

This discovery not only establishes a new fundamental principle for refrigeration but provides the scientific foundation for developing next-generation cooling technologies that combine environmental sustainability with commercial-grade performance requirements.

For underwater archaeologist Tseung Pak-long, the ocean’s surface tranquility often masks the volatile conditions that determine the success or failure of his missions. Recently traveling nearly eight hours from Hong Kong to Pingtan Island in Fujian province, Tseung arrived to assist with specialized diving training despite an approaching typhoon threatening to disrupt operations.

The delicate dance between archaeology and meteorology becomes most apparent during typhoon season, which spans May through November with peak intensity from July to September. Paradoxically, this period of heightened weather risk offers the most favorable underwater conditions for archaeological work. ‘Temperature and seabed conditions reach their optimal state during these months,’ Tseung explained, highlighting the profession’s inherent contradictions.

As Typhoon Wipha prompted Hong Kong’s highest hurricane warning, Tseung maintained hope that Fujian’s distance from the storm’s eye might spare their operations. This optimism proved short-lived as powerful gusts greeted his arrival, signaling the challenging conditions ahead.

The following day brought deceptive sunshine, but Tseung’s experience told a different story. ‘Favorable conditions for underwater work aren’t about surface weather,’ he clarified. ‘Everything depends on current intensity and subaquatic visibility.’

Underwater archaeology operates under stringent safety protocols that prioritize diver security above all discoveries. The discipline mandates buddy systems, strict time limitations, defined operational ranges, and precise workflows. Tseung gestured toward the seemingly calm sea, noting its appearance belied the turbulent currents churning beneath—the aftermath of the passing typhoon creating dangerous and murky conditions.

Accustomed to weather-related disappointments, Tseung philosophically compared underwater excavation to ‘opening a mystery box’ where even reaching a shipwreck site doesn’t guarantee significant findings. This unpredictability makes every successful dive particularly valuable.

The expedition’s fate was sealed by evening when rough seas forced all vessels to designated safe zones, canceling the next day’s planned operations. Accepting nature’s authority with equanimity, Tseung reflected that being at mercy of the elements simply represents the norm in his profession.

On the coastal frontier of Pingtan Island in Fujian province, where terrestrial landscapes merge with oceanic expanses, an unassuming four-story crimson structure houses China’s premier Underwater Archaeology Training Base. This facility represents the vanguard of the nation’s systematic efforts to reclaim its submerged cultural heritage from oceanic depths.

The discipline of underwater archaeology has evolved from specialized pursuit to established scientific practice in China, with veteran practitioners like retired archaeologist Cui Yong—among the nation’s pioneering figures in submerged cultural exploration—witnessing its transformative journey. As former deputy director of the Guangdong Institute of Cultural Relics and Archaeology, Cui embodies the dedication driving China’s maritime preservation initiatives.

Recent exhibitions, including the display of salvaged relics from the renowned Nanhai One shipwreck at Hong Kong’s Heritage Discovery Centre in August 2024, demonstrate the growing public engagement with these archaeological recoveries. The fourteenth-century merchant vessel, discovered in 1987 and meticulously excavated from the South China Sea, has become a symbolic representation of China’s maritime historical legacy, yielding over 180,000 cultural artifacts that illuminate ancient trade networks.

China’s methodological approach combines advanced sonar mapping, remotely operated vehicles, and specialized diver training to investigate shipwrecks spanning from the Song Dynasty (960-1279) to the Qing Dynasty (1644-1911). These scientific endeavors not only recover physical artifacts but reconstruct historical narratives of maritime commerce, technological exchange, and cultural interaction along ancient trade routes.

The national investment in underwater archaeology reflects broader recognition of oceanic heritage as an integral component of cultural preservation, with training programs developing new generations of archaeologists equipped to handle the unique challenges of submerged excavation and conservation.

A groundbreaking archaeological discovery in the caves of Sulawesi, Indonesia, has unveiled what researchers now identify as the world’s oldest known cave art. Meticulous analysis by a joint Indonesian-Australian research team has determined that distinctive hand stencils adorning the cave walls date back an astonishing 67,800 years, predating all previously studied rock art.

The tan-colored artifacts were created through an sophisticated technique whereby prehistoric artists blew pigment over hands pressed against the cave surface, leaving behind precise negative outlines. Intriguingly, some stencils feature intentionally modified fingertips crafted to appear more pointed, suggesting symbolic or artistic intention beyond mere representation.

This extraordinary find, detailed in Wednesday’s edition of Nature, positions Sulawesi as a cradle of ancient artistic culture. To establish the precise chronology, researchers employed advanced dating methods on mineral crusts that had formed over the artwork through millennia.

Study author Maxime Aubert of Griffith University emphasized the significance of these stencils as evidence of a complex artistic tradition that potentially represented shared cultural practices among early human populations. While simpler markings on bones and stones exist from earlier periods, these Sulawesi creations represent the earliest emergence of figurative cave art.

The discovery fuels ongoing scientific debate regarding which human species created these artworks. Potential creators include Denisovans—an ancient human group inhabiting the region—or early Homo sapiens migrants from Africa. The distinctive anatomical details preserved in the stencils strongly suggest human authorship.

Separate figurative drawings found in the same cave system, depicting human forms, birds, and equine animals, were determined to be significantly younger at approximately 4,000 years old, indicating a long-standing artistic tradition.

Researchers believe additional, potentially older artworks may await discovery throughout Indonesia’s island network. This finding not only pushes back the timeline of human artistic expression but opens new avenues for understanding how creative traditions spread across ancient human populations.

As Aubert stated: ‘This discovery represents not an endpoint, but an invitation to continue our exploration of humanity’s artistic origins.’

A groundbreaking archaeological discovery on the Indonesian island of Sulawesi has revealed what scientists now identify as the world’s oldest known cave painting—a 67,800-year-old hand stencil that challenges long-held theories about human cognitive evolution. The remarkable find, documented in the journal Nature, predates the previous record-holder from Spain by approximately 1,100 years and fundamentally reshapes our understanding of when Homo sapiens developed symbolic imagination.

The ancient artwork, located in Liang Metanduno cave on Muna Island, features a sophisticated red pigment outline of a hand that was intentionally modified to create a claw-like appearance. This deliberate artistic transformation represents an early leap in abstract thinking—the kind of cognitive processing that underpins language, religion, and scientific reasoning. Unlike simple impressions, this artwork demonstrates purposeful creative expression that researchers describe as ‘a very human thing to do.’

Professor Adam Brumm of Australia’s Griffiths University, who co-led the research, emphasizes that this discovery dismantles the Eurocentric notion of a ‘creative explosion’ occurring exclusively in Ice Age Europe. ‘We’re seeing traits of modern human behavior, including narrative art in Indonesia, which makes that argument very hard to sustain,’ Brumm stated. The evidence now suggests that creativity was innate to our species from its African origins rather than suddenly emerging in European populations.

The dating methodology employed uranium-series analysis of mineral crusts covering the artwork, providing a minimum age of 67,800 years. This technological advancement has consistently pushed back the timeline of sophisticated image-making in Sulawesi, where previous discoveries included 40,000-year-old hand stencils, a 44,000-year-old hunting scene, and a 51,200-year-old narrative painting.

Crucially, the discovery’s location on the northern sea route between mainland Asia and the ancient Australia-New Guinea landmass (Sahul) has significant implications for human migration patterns. The confirmed presence of symbolically-capable humans in Sulawesi over 67,000 years ago lends credibility to controversial evidence suggesting human occupation in northern Australia by approximately 65,000 years ago—potentially resetting the timeline of Aboriginal Australian ancestry by 15,000 years.

Indonesian researcher Adhi Agus Oktaviana of the national research and innovation agency (BRIN) notes that the artists were likely part of a broader population that eventually spread throughout the region and reached Australia. The finding supports an emerging consensus that symbolic behavior was established in Africa long before Homo sapiens migrated globally, with creative expression manifesting independently across multiple regions over tens of thousands of years.

In a landmark discovery with profound implications for planetary science, Chinese researchers have confirmed the natural formation of single-walled carbon nanotubes and graphitic carbon within lunar samples retrieved by the Chang’e-6 mission. The China National Space Administration officially announced these findings on Tuesday, revealing unprecedented insights into the moon’s geological complexity.

A scientific team from Jilin University employed advanced microscopic and spectroscopic methodologies to conduct a comprehensive examination of far-side lunar material. Their investigation yielded the first definitive verification of naturally occurring graphite carbon on the lunar surface, simultaneously tracing its probable formation mechanisms and evolutionary trajectory.

This research achieves dual historical significance: it establishes the first international confirmation that single-walled carbon nanotubes can form through natural processes without anthropogenic intervention, while simultaneously demonstrating the sophisticated high-energy physico-chemical activities occurring on the lunar surface. The evidence points toward more dynamic geological processes on the moon’s far side than previously understood.

The study proposes that nanotube formation likely resulted from iron-catalyzed reactions driven by multiple extraterrestrial factors throughout lunar history. These include persistent micrometeorite bombardment, ancient volcanic phenomena, and continuous solar wind irradiation—collectively creating extreme conditions that enabled nature’s synthesis of advanced carbon structures.

Comparative analysis between Chang’e-6’s far-side samples and Chang’e-5’s near-side specimens revealed distinctive structural differences. Carbon formations from the far side exhibited more pronounced defect characteristics, potentially indicating intensified micrometeorite impacts throughout the moon’s geological history. This discrepancy suggests previously unrecognized compositional and evolutionary asymmetries between the lunar hemispheres.

These groundbreaking findings, recently published in the prestigious journal Nano Letters, fundamentally reshape our understanding of lunar geology and demonstrate how extreme cosmic environments can spontaneously generate advanced nanomaterials through natural processes.