Fluorescence-based imaging has emerged as a powerful tool for detecting latent fingerprints(LFPs).However,existing fluorescent developers face challenges in differentiating friction ridges from backgrounds with intrac...Fluorescence-based imaging has emerged as a powerful tool for detecting latent fingerprints(LFPs).However,existing fluorescent developers face challenges in differentiating friction ridges from backgrounds with intractable fluorescence,and to date,post-processing techniques fail to effectively enhance poorly visualized fingerprints.Herein,trichromatic-emitting carbon dots(CDs)were synthesized via a one-step solvothermal method using dyes and ethylene glycol as precursors.Experimental and theoretical results revealed that the high photostability and photobleaching resistance of the synthesized CDs originated from the hydrogen-bond interactions between the carbonaceous matrix and dye-related functional groups and fragments,which served as the fluorophore of these Dye-CDs.By combining CDs with diatomite,the resulting composite powders demonstrated high sensitivity and selectivity in fluorescence visualization of both fresh and aging LFPs.Using a typical powdering method with Dye-CDs/diatomite stored for 30 days,levels 1–3 detailed features of LFPs deposited on various porous or non-porous substrates were identified with high contrast.The developed tunable multicolor post-processing technique,achieved by separating ridge patterns from background noise,ensured highresolution details and overcame the challenges of weakly developed fingerprints.Thus,the proposed dual-mode strategy provides a promising solution for practical fingerprint imaging.展开更多
With the improvement of people’s living standards,a large number of petroleum products,daily necessities and decorations that can produce volatile organic compounds are used in decoration,which seriously affects the ...With the improvement of people’s living standards,a large number of petroleum products,daily necessities and decorations that can produce volatile organic compounds are used in decoration,which seriously affects the indoor air quality.Interior decoration materials have become a research hotspot in recent years.The purpose of this paper is to develop a kind of interior wall material with good indoor formaldehyde removal effect,easily using,and low cost.In this paper,combining different heat treatment temperatures of the glaze layer,tourmaline/diatomite-based interior wall tiles were prepared by ultrafine grinding,solid sintering,and low temperature calcination.The glaze layer under different heat treatment temperatures was characterized by thermogravimetric-differential thermal analysis,X-ray diffraction,and scanning electron microscope.The influences of heat treatment temperature on the microscopic morphology and structure of the glaze layer were analyzed.Taking formaldehyde as the target degradation product,the effects of tourmaline/diatomite-based interior wall tiles on the removal of formaldehyde under different heat treatment temperatures of the glaze layer were investigated.The results showed that with the increase in heat treatment temperature,the original pores of diatomite decreased,the specific surface area decreased,and the structure of tourmaline changed.At 850℃,the surface structure of the material was slightly damaged,the strength was increased,and the removal effect of formaldehyde was better.In a 1 m^(3) environmental chamber,the formaldehyde removal rate reached 73.6%in 300 min.When the temperature was increased to 950℃ and above,diatomite and the structure of tourmaline were destroyed,and the ability of the material to adsorb and degrade formaldehyde decreased.展开更多
基金supported by the Key Laboratory of Impression Evidence Examination and Identification Technology,Criminal Investigation Police University of China,Ministry of Public Security,People’s Republic of China(No.2018HJKF12)the Natural Science Foundation of Liaoning Province(No.2023-BS-081)the Foundation of Education Department of Liaoning Province(Nos.LJKMZ20221366 and LJKQZ20222296).
文摘Fluorescence-based imaging has emerged as a powerful tool for detecting latent fingerprints(LFPs).However,existing fluorescent developers face challenges in differentiating friction ridges from backgrounds with intractable fluorescence,and to date,post-processing techniques fail to effectively enhance poorly visualized fingerprints.Herein,trichromatic-emitting carbon dots(CDs)were synthesized via a one-step solvothermal method using dyes and ethylene glycol as precursors.Experimental and theoretical results revealed that the high photostability and photobleaching resistance of the synthesized CDs originated from the hydrogen-bond interactions between the carbonaceous matrix and dye-related functional groups and fragments,which served as the fluorophore of these Dye-CDs.By combining CDs with diatomite,the resulting composite powders demonstrated high sensitivity and selectivity in fluorescence visualization of both fresh and aging LFPs.Using a typical powdering method with Dye-CDs/diatomite stored for 30 days,levels 1–3 detailed features of LFPs deposited on various porous or non-porous substrates were identified with high contrast.The developed tunable multicolor post-processing technique,achieved by separating ridge patterns from background noise,ensured highresolution details and overcame the challenges of weakly developed fingerprints.Thus,the proposed dual-mode strategy provides a promising solution for practical fingerprint imaging.
基金financially supported by the Natural Science Foundation of China (No. 50708037)the National Science Fund for Excellent Young Scholars of China (No. 51522402)
文摘With the improvement of people’s living standards,a large number of petroleum products,daily necessities and decorations that can produce volatile organic compounds are used in decoration,which seriously affects the indoor air quality.Interior decoration materials have become a research hotspot in recent years.The purpose of this paper is to develop a kind of interior wall material with good indoor formaldehyde removal effect,easily using,and low cost.In this paper,combining different heat treatment temperatures of the glaze layer,tourmaline/diatomite-based interior wall tiles were prepared by ultrafine grinding,solid sintering,and low temperature calcination.The glaze layer under different heat treatment temperatures was characterized by thermogravimetric-differential thermal analysis,X-ray diffraction,and scanning electron microscope.The influences of heat treatment temperature on the microscopic morphology and structure of the glaze layer were analyzed.Taking formaldehyde as the target degradation product,the effects of tourmaline/diatomite-based interior wall tiles on the removal of formaldehyde under different heat treatment temperatures of the glaze layer were investigated.The results showed that with the increase in heat treatment temperature,the original pores of diatomite decreased,the specific surface area decreased,and the structure of tourmaline changed.At 850℃,the surface structure of the material was slightly damaged,the strength was increased,and the removal effect of formaldehyde was better.In a 1 m^(3) environmental chamber,the formaldehyde removal rate reached 73.6%in 300 min.When the temperature was increased to 950℃ and above,diatomite and the structure of tourmaline were destroyed,and the ability of the material to adsorb and degrade formaldehyde decreased.
