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We developed two simple, rapid, and cost-effective fluorescent nanosensors, both featuring bovine serum albumin labeled with fluorescein isothiocyanate (FITC))-capped gold nanoparticles (FITC-BSA-Au NPs), for the selective sensing of cyanide (CN(-)) and iodine (I(-)) ions in high-salinity solutions and edible salt samples. During the preparation of FITC-BSA-Au NP probes, when AuNPs were introduced to the mixture containing FITC and BSA, the unconjugated FITC and FITC-labeled BSA (FITC-BSA) adsorbed to the particles' surfaces. These probes operated on a basic principle that I(-) and CN(-) deposited on the surfaces of the Au NPs or the etching of Au NPs induced the release of FITC molecules or FITC-BSA into the solution, and thus restored the florescence of FITC. We employed FITC-BSA to protect the Au NPs from significant aggregation in high-salinity solutions. In the presence of masking agents such as S(2)O(8)(2-)/Pb(2+), FITC-BSA-Au NPs facilitated the selective detection of CN(-) (by at least 150-fold in comparison with other anions). We also demonstrated that the FITC-BSA-Au NPs in the presence of H(2)O(2) could selectively detect I(-) down to 50 nM. Taking advantages of their high stability and selectivity, we employed our FITC-BSA-Au NP-based probes for the detection of CN(-) and I(-) in water samples (pond water, tap water, and seawater) and detection of I(-) in edible salt samples, respectively. This simple, rapid, and cost-effective sensing system appears to demonstrate immense practical potential for the detection of anions in real samples.

We have developed a simple, colorimetric, and label-free tellurium nanowire (Te NW)-based probe for the detection of mercuryions (Hg(II)) in aqueoussolution, operating on the principle of strong hybridization and galvanic replacement reaction of Te–Hg. The Te NWs (length: 920 nm; diameter: 20 nm) reacted with Hg(II) to induce dissolution and aggregation of the Te NWs. As a result, the absorption band of the Te NWs in a solution undergoes a decrease in the presence of Hg(II). Energy-dispersive X-ray spectroscopy and surface-assisted laser desorption/ionization measurements demonstrated the presence of Hg on the Te NWs. The Te NW probe specifically and sensitively detected Hg(II) ions under optimal concentrations of pH, temperature, and sodiumdodecyl sulfate (SDS) concentration. When using a mixture of Te NWs (3.0 nM) and SDS (5M) in 5 mM sodium phosphate (pH 4) at 50 °C, this sensor provides a limit of detection of 0.5 nMfor Hg(II) (signal-to-noiseratioof 3) with high selectivity(atleast100 fold over other metal ions). Our approach abrogates the need for complicated chemosensors or sophisticated equipment. This cost-effective sensing system allows the rapid and simple determination of the concentrations of Hg(II) ions in real samples (in this case, river, lake, and tap water samples).

We have developed a simple paper-based colorimetric membrane for sensing lead ions (Pb(2+)) in aqueous solutions. The nitrocellulose membrane (NCM) was used to trap bovine serum albumin (BSA) modified 13.3-nm Au nanoparticles (BSA-Au NPs), leading to the preparation of a nanocomposite film of a BSA-Au NP-decorated membrane (BSA-Au NPs/NCM). The BSA-Au NPs/NCM operates on the principle that Pb(2+) ions accelerate the rate of leaching of Au NPs induced by thiosulfate (S(2)O(3)(2-)) and 2-mercaptoethanol (2-ME). The BSA-Au NPs/NCM allowed for the detection of Pb(2+) by the naked eye in nanomolar aqueous solutions in the presence of leaching agents such as S(2)O(3)(2-) and 2-ME. We employed the assistance of microwave irradiation to shorten the reaction time (10 min) for leaching the Au NPs. Under optimal solution conditions (5 mM glycine-NaOH (pH 10), S(2)O(3)(2-) (100 mM), and 2-ME (250 mM), microwaves (450 W)), the BSA-Au NPs/NCM allowed the detection of Pb(2+) at concentrations as low as 50 pM with high selectivity (at least 100-fold over other metal ions). This cost-effective sensing system allowed for the rapid and simple determination of the concentrations of Pb(2+) ions in real samples (in this case, sea water, urine, and blood samples).

We have developed a simple, low-cost, paper-based probe for the selective colorimetric detection of copper ions (Cu(2+)) in aqueous solutions. The bovine serum albumin (BSA)-modified 13.3-nm Au nanoparticle (BSA-Au NP) probe was designed to detect Cu(2+) ions using lead ions (Pb(2+)) and 2-mercaptoethanol (2-ME) as leaching agents in a glycine-NaOH (pH 12.0) solution. In addition, a nitrocellulose membrane (NCM) was used to trap the BSA-Au NPs, leading to the preparation of a nanocomposite film consisting of a BSA-Au NP-decorated membrane (BSA-Au NPs/NCM). The BSA-Au NPs probe operates on the principle that Cu deposition on the surface of the BSA-Au NPs inhibits their leaching ability, which is accelerated by Pb(2+) ions in the presence of 2-ME. Under optimal solution conditions (5 mM glycine-NaOH (pH 12.0), Pb(2+) (50 μM), and 2-ME (1.0 M)), the Pb(2+)/2-ME-BSA-Au NPs/NCM enabled the detection of Cu(2+) at nanomolar concentrations in aqueous solutions by the naked eye with high selectivity (at least 100-fold over other metal ions). In addition, this cost-effective probe allowed for the rapid and simple determination of Cu(2+) ions in not only natural water samples but also in a complex biological sample (in this case, blood sample).

This paper describes the use of two types of bovine serum albumin (BSA)-capped 14.2 nm diameter gold nanoparticles (Au NPs) for the separate detection of mercury (Hg2+) and lead (Pb2+) ions in highly saline media. The BSA-capped Au NPs were stable in solutions containing up to 500 mM NaCl. Introduction of BSA to a solution of rhodamine 6G (R6G) and 3-mercaptopropionic acid (MPA)-modified Au NPs (R6G/MPA–Au NPs) provided a R6G/MPA–Au NP@BSA probe for the sensing of Hg2+ ions. We also used BSA-capped Au NPs to detect Pb2+ ions through a mechanism based on Pb2+ ions accelerating the leaching rate of Au NPs in the presence of thiosulfate (S2O32−) and 2-mercaptoethanol (2-ME). The resulting deposition of Hg2+ ions onto the Au NPs induced the release of R6G from the surfaces of the Au NPs, causing increased fluorescence from the R6G/MPA–Au NP@BSA solution. The Pb2+ ions accelerated the dissolution of the 2-ME/S2O32−–Au NPs@BSA into solution, leading to dramatic decreases in the absorption. These two Au NP-based probes were highly sensitive (LOD ≈ nM) and selective (over 100-fold against other metal ions) toward Hg2+ or Pb2+ ions. We validated the practicality of these two probes through analyses of seawater and urine samples. We also developed a simple gel-based membrane for removal and sensing of Hg2+ or Pb2+ in aqueous solutions. The agarose gel was used to trap BSA-Au NPs, leading to the preparation of a nanocomposite film of Au NPs@BSA-decorated agarose gel membrane (Au NPs@BSA/AGM) for removing Hg2+ or Pb2+ in solution. In addition, R6G/MPA–Au NP@BSA-trapped agarose gel membrane (R6G/MPA–Au NP@BSA/AGM) and 2-ME/S2O32−–Au NPs@BSA/AGM allowed for the rapid and simple detection of Hg2+ and Pb2+, respectively.

This paper presents a multiple-objective real-time scheduler for semiconductor wafer fab using Colored Timed Object-oriented Petri net (CTOPN). First, a high-fidelity hierarchical CTOPN model of wafer fab is constructed, upon which a hierarchical control system is also formed. To rank WIP lots in meeting multiple scheduling objectives, a combined priority index is then developed in the fab level controller. To cope with unpredictable events occurred on the equipments, such as breakdown, real-time dispatching policies are encapsulated in the work station-level controllers, which dynamically dispatch wafer lot, and the dispatching results are fed back to fab controller through work area controllers.