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91.
The sorption/desorption characteristics of heavy metals onto/from soil particle surfaces are the primary factors controlling the success of the remediation of heavy-metal contaminated soils. These characteristics are pH-dependent, chemical-specific, and reversible; and can be modified by enhancement agents such as chelates and surfactants. In this study, batch experiments were conducted to evaluate the feasibility of using citric acid industrial wastewater (CAIW) to desorb cadmium from a natural clay from Shanghai, China at different soil mixture pHs. It can be observed from the results that the proportion of cadmium desorbed from the soil using synthesized CAIW is generally satisfactory, i.e., >60%, when the soil mixture pH is lower than 6. However, the proportion of desorbed cadmium decreases significantly with increase in soil mixture pH. The dominant cadmium desorption mechanism using CAIW is the complexion of cadmium with citric acid and acetic acid in CAIW. It is concluded that CAIW can be a promising enhancement agent for the remediation of cadmium-contaminated natural soils when the environmental conditions are favorable. As a result, CAIW, a waste product itself, can be put into productive use in soil remediation. 相似文献
92.
Herein, we demonstrated a new optical microscopy method to selectively image small-size gold nanoparticles (GNPs) inside noisy living cells through determination of the difference image between the probe beam (illuminated at the resonance wavelength of GNPs, 532 nm) and the reference beam (illuminated at 473 nm). From computer simulation and single-particle imaging experiments, we demonstrated that GNPs with a diameter of 45 nm could be selectively imaged in the GNPs/cell lysates mixture and inside living cells by dual-wavelength difference (DWD) imaging. The diffusion dynamics of nucleic acids functionalized GNPs on cell membranes and the internalization kinetics of these GNPs by living cells were explored with this method. Our real-time tracking experiments showed that statistically 80% of GNPs were under restricted diffusion on the cell membrane. The cell cytoskeleton fence effect, as observed in the single-particle tracking experiments, may be one of the main factors for the restricted diffusion mode. 相似文献
93.
Facile Generation of L10‐FePt Nanodot Arrays from a Nanopatterned Metallopolymer Blend of Iron and Platinum Homopolymers
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Qingchen Dong Guijun Li Cheuk‐Lam Ho Chi‐Wah Leung Philip Wing‐Tat Pong Ian Manners Wai‐Yeung Wong 《Advanced functional materials》2014,24(6):857-862
Hard ferromagnetic (L10 phase) FePt alloy nanoparticles (NPs) with extremely high magnetocrystalline anisotropy are considered to be one of the most promising candidates for the next generation of ultrahigh‐density data storage system. The question of how to generate ordered patterns of L10‐FePt NPs and how to transform the technology for practical applications represents a key current challenge. Here the direct synthesis of L10 phase FePt NPs by pyrolysis of Fe‐containing and Pt‐containing metallopolymer blend without post‐annealing treatment is reported. Rapid single‐step fabrication of large‐area nanodot arrays (periodicity of 500 nm) of L10‐ordered FePt NPs can also be achieved by employing the metallopolymer blend, which possesses excellent solubility in most organic solvents and good solution processability, as the precursor through nanoimprint lithography (NIL). Magnetic force microscopy (MFM) imaging of the nanodot pattern indicates that the patterned L10 phase FePt NPs are capable of exhibiting decent magnetic response, which suggests a great potential to be utilized directly in the fabrication of bit patterned media (BPM) for the next generation of magnetic recording technology. 相似文献
94.
Baranyi P. Varkonyi-Koczy A.R. Yeung Yam Patton R.J. 《IEEE transactions on instrumentation and measurement》2005,54(1):52-60
One direction of measured data-set based modeling applies fuzzy logic identification tools and results in a fuzzy rule-base model. A typical problem of fuzzy identification methods is that the complexity of the resulting fuzzy rule-base, namely the number of rules in the rule-base, explodes with the modeling accuracy. As a result, the topic of fuzzy rule-base complexity reduction techniques emerged in the last decade. A common disadvantage of fuzzy rule-base complexity reduction methods is that the resulting complexity minimized fuzzy-rule bases cannot be simply adapted to new information. If we have new information that cannot be described by the fuzzy rules of the complexity minimized fuzzy rule-base, then we have two choices. The first choice is to add new fuzzy rules to the fuzzy rule-base until the new information can be described. The second choice is to modify the new information until it can be described by the fuzzy rule-base without using additional fuzzy rules. This second case has the prominent role if the number of fuzzy rules in the fuzzy rule-base is limited. This paper proposes a method for the second choice. The proposed method minimizes the necessary modification of the new information. This paper focuses attention on a recent complexity reduction method, termed Higher Order Singular Value Decomposition (HOSVD)-based complexity reduction, and Takagi-Sugeno (TS) inference operator-based fuzzy rule-bases. An example is used to provide the validation of the proposed method. In order to demonstrate the effectiveness of the proposed method, a control system of a differential-steered automatic guided vehicle is modeled in the paper. 相似文献
95.
The concept of providing energy conservation programs with monitoring and control via two-way communication (TWCC) systems will be one of the solutions that utilities will employ in the conservation of the nation's valuable natural resources. The development of microelectronic technology is changing the manner in which meters will be read. There are many methods currently available in the market that enable retrieval of data remotely from a customer's premise. The potential of this technology and its applications can be endless. In the area of automatic meter reading (AMR), current technology is in a state of evolution where no single method excels. Development of the new “information superhighway” industry is likely to promote standards based upon open systems and open protocols. Current AMR technologies are described 相似文献
96.
97.
98.
CC Szeto CC Chow KY Li TC Ko VT Yeung CS Cockram 《Canadian Metallurgical Quarterly》1996,35(3):289-291
We report a case of oesophageal disease as the first manifestation in a patient with CREST syndrome. A 46-year-old man with achalasia-like syndrome developed CREST syndrome 4 years later. A pneumatic dilatation of the cardia was performed. After pneumatic dilatation the dysphagia and regurgitation disappeared but the patient developed reflux oesophagitis. Four years after diagnosis of oesophageal disease he presented with a clinical picture of CREST syndrome. An acute ileus and constipation developed later. After receiving medical therapy with omeprazole and cisapride the patient is free of oesophageal symptoms and bowel movements are normal. Oesophageal disease is common in patients with limited and diffuse scleroderma, but to our knowledge achalasia-like syndrome has not been previously described as the first manifestation of the systemic disease. 相似文献
99.
Shin K. Weize Xiong Chung Yeung Cho Cleavelin C.R. Schulz T. Schruefer K. Patruno P. Smith L. Tsu-Jae King Liu 《Electron Device Letters, IEEE》2006,27(8):671-673
The impact of stress induced by biaxial mechanical bending on multiple-gate FET (MuGFET) performance is studied. For relatively low levels of bending-induced surface strain (/spl sim/ 0.1%), significant enhancements in the driving current can be achieved and maintained with gate-length scaling. This makes package strain a potentially attractive approach to enhancing MuGFET-based CMOS performance at low cost. For bending-induced strain, the enhancements in electron mobility and [110] hole mobility are well predicted by the piezoresistance model using the coefficients for bulk-Si, but the impact of stress on (100) hole mobility is more complex. 相似文献
100.
B Balasa JD Davies J Lee A Good BT Yeung N Sarvetnick 《Canadian Metallurgical Quarterly》1998,161(8):4420-4427
IL-10 is essential for an early phase of diabetes in nonobese diabetic (NOD) mice, but later becomes protective against its development. The mechanism by which IL-10 mediates the pathway to diabetes in these mice is unknown. Herein, we dissected the cellular and costimulation requirements for diabetes in transgenic (tg) NOD mice that expressed IL-10 in their pancreatic islets (IL-10-NOD mice). We found that IL-10 alone did not cause diabetes because the offspring (IL-10-NOD-scid mice) from back-crosses of IL-10-NOD mice with NOD-scid mice had no diabetes. Moreover, these IL-10-NOD-scid mice were free of lymphocytic infiltration. Treatment of IL-10-NOD mice with depleting anti-CD4 mAb or control mAb had no effect on diabetes. Surprisingly, depletion of CD8+ T cells by treatment with the corresponding mAb inhibited diabetes without attenuating insulitis, demonstrating a critical role for CD8+ T cells in the disease process. Interestingly, B cell-deficient IL-10-NOD mice readily developed diabetes with kinetics and incidence similar to those observed in wild-type mice, demonstrating that B lymphocytes as APCs were not required in the disease process. Administration of anti-CD40 ligand (CD40L) mAb did not prevent disease, indicating that CD40/CD40L costimulation is not required for diabetes in IL-10-NOD mice. Immunization of IL-10-NOD mice with CFA or heat-shock protein 65, known to block diabetes in NOD mice, had no effect on their diabetes. We demonstrate that IL-10 contributes early to the pathology of diabetes via a CD8+ T cell pathway, eliminating the requirement for B lymphocytes and CD40-CD40L costimulation. Our findings provide a mechanism for the participation of IL-10 in the early development of diabetes. 相似文献